[Andy Katz]

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

Andy Katz

[bob]

Andy Katz wrote:
I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well.

That is bit surprising, given that the minimum recommended amplifier
power for that speaker is more than 3 times the claimed power for that
amp.

Then I thought, why leave well enough alone? My
pre-amp has both a CD

Huh?

and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over

Do you mean that you removed the metal strap connecting the upper and
lower speaker terminals? That's not the crossover.

and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

"Valid" is in the ear of the beholder. But an obvious problem with this
set-up, if I understand it correctly, is that every time you want to
change the volume, you've got to set two (or three!) levels
independently. And every time you do that, you're going to be changing
the tonal balnace of your system. I can't imagine why you'd want to do
that, although some recent threads suggest you are not alone.

bob

[Andy Katz]

On 23 Sep 2006 15:47:05 GMT, "bob" wrote:

Andy Katz wrote:
I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well.

That is bit surprising, given that the minimum recommended amplifier
power for that speaker is more than 3 times the claimed power for that
amp.

My thoughts exactly. I bought the Dared to use as a usb dap and
headphone amp. Connecting the B&Ws was just a lark.

Then I thought, why leave well enough alone? My
pre-amp has both a CD

Huh?

Okay, I ought to have looked before trying to describe it. The
pre-amp, a Luxman TP 114, has set of jacks labeled "pre out". One set
is fixed the other variable. When I connect anything to the fixed set
they send what appears to be the unregulated signal of the particular
selected source--cd, tuner, etc. I had been using that out with my
Perreaux Silhouette, enabling both speaker and headphone play
simultaneously.

and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over

Do you mean that you removed the metal strap connecting the upper and
lower speaker terminals?

Yes. I did.

That's not the crossover.

Oh.

If it's not the crossover, what is it?

and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

"Valid" is in the ear of the beholder. But an obvious problem with this
set-up, if I understand it correctly, is that every time you want to
change the volume, you've got to set two (or three!) levels
independently.

That's right. I have to set two. Because of its lower power rating, I
connected the Dared to the B&W's high range and the Yamaha to its
lower.

And every time you do that, you're going to be changing
the tonal balnace of your system. I can't imagine why you'd want to do
that, although some recent threads suggest you are not alone.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

I appreciate the comments.

Andy Katz

[bob]

Andy Katz wrote:
On 23 Sep 2006 15:47:05 GMT, "bob" wrote:

Andy Katz wrote:

and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over

Do you mean that you removed the metal strap connecting the upper and
lower speaker terminals?

Yes. I did.

That's not the crossover.

Oh.

If it's not the crossover, what is it?

Well...it's the metal strap connecting the upper and lower speaker
terminals. The actual crossover is circuitry inside the speaker.
Basically, there's a high-pass filter feeding the tweeter and a
low-pass filter feeding the woofer. There is a form of bi-amping
("active") which involves disconnecting those filters and using an
outboard electronic filter instead. I didn't think that's what you were
doing, but I wanted to be clear.

and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

OK, that works.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

"Valid" is in the ear of the beholder. But an obvious problem with this
set-up, if I understand it correctly, is that every time you want to
change the volume, you've got to set two (or three!) levels
independently.

That's right. I have to set two. Because of its lower power rating, I
connected the Dared to the B&W's high range and the Yamaha to its
lower.

And every time you do that, you're going to be changing
the tonal balnace of your system. I can't imagine why you'd want to do
that, although some recent threads suggest you are not alone.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

bob

[Jerry]

bob wrote on 9/23/2006:

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

OK, that works.

Bob, is right it works, but chances are the audio signal is out of phase on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most likely
180 degrees out-of-phase with each other. To get trhe signals back in
phase:

1. use pre-out for both power amps
2. sent the TAPE OUTPUT into the AUX on the Yamaha and run through the tone
control amp to get the signals back in phase

Unfortunately, this just gets the signals phased correctly into the power
amps. Since we are talking different technologies here, these amps could be
reversing the phase again.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

Andy, your DARED is a fairly low power unit, but it has more than sufficient
power to handle the tweeters in your CM2's. In fact, I doubt the tweeters
in the CM2's can handle the full power of the DARED. Typically tweeters
consume 5% to 7% of the audio power.

Nevertheless, there could still be a problem with the DARED and it could
damage your tweeters. What causes most of the blown tweeters is clipping
and the resulting distortion. Clipping occurs when the audio signal is so
large that it exceeds the rail voltages ... anywhere in the power amp.

I realize this is confusing. My amp has plenty of power, but it could still
damage my speakers???

Problem is power is a measure of voltage and current. Clipping is caused by
running out of just ... voltage.

Fortunately, Andy, there is a very simple solution. Don't send the lowest
frequencies to the DARED. Set the bass tone control all the way OFF and you
will create enormous headroom within the DARED. To see how this works read:

http://audiokarma.org/forums/showthread.php?t=81094

Hope this helps ....

Regards,
Jerry

[[email protected]]

Jerry wrote:
Clipping is caused by running out of just ... voltage.

That would be "voltage" or voltage limiting. It's also quite
possible to run into "current" clipping as well, better known
as "current limiting," reached when you have hit the current
capacity of the amplifier.

[Andy Katz]

On 23 Sep 2006 20:26:31 GMT, "bob" wrote:

If it's not the crossover, what is it?

Well...it's the metal strap connecting the upper and lower speaker
terminals. The actual crossover is circuitry inside the speaker.
Basically, there's a high-pass filter feeding the tweeter and a
low-pass filter feeding the woofer. There is a form of bi-amping
("active") which involves disconnecting those filters and using an
outboard electronic filter instead. I didn't think that's what you were
doing, but I wanted to be clear.

Right. I haven't done anything internally to the speakers.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

"Valid" is in the ear of the beholder. But an obvious problem with this
set-up, if I understand it correctly, is that every time you want to
change the volume, you've got to set two (or three!) levels
independently.

That's right. I have to set two. Because of its lower power rating, I
connected the Dared to the B&W's high range and the Yamaha to its
lower.

And every time you do that, you're going to be changing
the tonal balnace of your system. I can't imagine why you'd want to do
that, although some recent threads suggest you are not alone.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Oh, of course. I see .... using the fixed out was a mistake.

In that case would it be feasible to use an RCA doubler and connect
both amps into the pre-amp variable out?

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

Right. I understand.

Thanks for the explanation and advice. It really did clear up a few
things;-)

Andy Katz

[bob]

Jerry wrote:
bob wrote on 9/23/2006:

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

OK, that works.

Bob, is right it works, but chances are the audio signal is out of phase on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most likely
180 degrees out-of-phase with each other.

Hadn't thought of phase. I did wonder whether there would be some
impedance problem driving two amps, one of them a frou-frou tube
design, out of a single set of pre-out jacks. Not saying, just asking.

To get trhe signals back in
phase:

1. use pre-out for both power amps
2. sent the TAPE OUTPUT into the AUX on the Yamaha and run through the tone
control amp to get the signals back in phase

Unfortunately, this just gets the signals phased correctly into the power
amps. Since we are talking different technologies here, these amps could be
reversing the phase again.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

Andy, your DARED is a fairly low power unit, but it has more than sufficient
power to handle the tweeters in your CM2's. In fact, I doubt the tweeters
in the CM2's can handle the full power of the DARED. Typically tweeters
consume 5% to 7% of the audio power.

Nevertheless, there could still be a problem with the DARED and it could
damage your tweeters. What causes most of the blown tweeters is clipping
and the resulting distortion. Clipping occurs when the audio signal is so
large that it exceeds the rail voltages ... anywhere in the power amp.

I realize this is confusing. My amp has plenty of power, but it could still
damage my speakers???

Problem is power is a measure of voltage and current. Clipping is caused by
running out of just ... voltage.

Fortunately, Andy, there is a very simple solution. Don't send the lowest
frequencies to the DARED. Set the bass tone control all the way OFF and you
will create enormous headroom within the DARED.

Except that, if he takes your advice above and runs both amps out of
his pre-out jacks, then this will also affect the bass response of the
woofer. Youar approach would only work for him if he ran the woofer amp
off the tape out jacks (with phase problems noted), which aren't
affected by the tone controls on the preamp.

To see how this works read:

http://audiokarma.org/forums/showthread.php?t=81094

You could post this on a thousand different Web sites, Jerry, and you'd
still be a minority of one!

bob

[bob]

Jerry wrote:
bob wrote on 9/23/2006:

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

OK, that works.

Bob, is right it works, but chances are the audio signal is out of phase on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most likely
180 degrees out-of-phase with each other.

Hadn't thought of phase. I did wonder whether there would be some
impedance problem driving two amps, one of them a frou-frou tube
design, out of a single set of pre-out jacks. Not saying, just asking.

To get trhe signals back in
phase:

1. use pre-out for both power amps
2. sent the TAPE OUTPUT into the AUX on the Yamaha and run through the tone
control amp to get the signals back in phase

Unfortunately, this just gets the signals phased correctly into the power
amps. Since we are talking different technologies here, these amps could be
reversing the phase again.

No. Clearly you're right. I'm not. I've been trying to follow some of
the discussion on bi-amping and while it's very interesting, none of
it seems to apply to my situation. I'm afraid I still can't picture
what a properly bi-amped system would resemble. Two amps supply the
power, but their speaker outs are connected to ... what? Something has
to regulate or coordinate their output, right?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

Andy, your DARED is a fairly low power unit, but it has more than sufficient
power to handle the tweeters in your CM2's. In fact, I doubt the tweeters
in the CM2's can handle the full power of the DARED. Typically tweeters
consume 5% to 7% of the audio power.

Nevertheless, there could still be a problem with the DARED and it could
damage your tweeters. What causes most of the blown tweeters is clipping
and the resulting distortion. Clipping occurs when the audio signal is so
large that it exceeds the rail voltages ... anywhere in the power amp.

I realize this is confusing. My amp has plenty of power, but it could still
damage my speakers???

Problem is power is a measure of voltage and current. Clipping is caused by
running out of just ... voltage.

Fortunately, Andy, there is a very simple solution. Don't send the lowest
frequencies to the DARED. Set the bass tone control all the way OFF and you
will create enormous headroom within the DARED.

Except that, if he takes your advice above and runs both amps out of
his pre-out jacks, then this will also affect the bass response of the
woofer. Youar approach would only work for him if he ran the woofer amp
off the tape out jacks (with phase problems noted), which aren't
affected by the tone controls on the preamp.

To see how this works read:

http://audiokarma.org/forums/showthread.php?t=81094

You could post this on a thousand different Web sites, Jerry, and you'd
still be a minority of one!

bob

[Andy Katz]

On 24 Sep 2006 02:34:09 GMT, "Jerry" wrote:

bob wrote on 9/23/2006:

Hold it. The Dared and the Yamaha are both *integrated* amps. Are you
saying you are using a preamp to feed two integrated amps? That's kinda
weird. For one thing, you've got volume controls all over the place. Or
maybe I'm just not picturing this correctly.

My bad. I ought to have explained, I was having trouble with the vol
pot on the Yamaha. It produced a crackling sound, probably from
corrosion. I tried cleaning it, but some interference remained. I also
needed a new tuner, so when I saw the Luxman for sale at a bargain I
picked it up. The Yamaha can be de-coupled and used solely as either a
power or control amp. So right now it's only a power amp, the Luxman
doing tuner and pre-amp duties.

OK, that works.

Bob, is right it works, but chances are the audio signal is out of phase on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most likely
180 degrees out-of-phase with each other. To get trhe signals back in
phase:

1. use pre-out for both power amps
2. sent the TAPE OUTPUT into the AUX on the Yamaha and run through the tone
control amp to get the signals back in phase

Unfortunately, this just gets the signals phased correctly into the power
amps. Since we are talking different technologies here, these amps could be
reversing the phase again.

Hmmm. Okay. Suppose I use an RCA splitter to connect both amps to the
same input?

The speaker outs are connected to the speakers, obviously. I think your
question is, how do you set this up so as to maintain the tonal balance
as you change volume. You need to hook both amps up to the pre-amp
through the jack(s) that are affected by the pre-amp's volume control.
Whether you can do that with the gear you have I don't know, but maybe
somebody else here can guide you. Use the volume control on the Dared
to balance it with the Yamaha, then don't touch it ever again. Just
control the volume via the pre-amp.

Also, I'm surprised to hear that the straps weren't the passive
cross-overs, because when I turned on the system using just the Dared
the only sound that came out was the high range. Then I turned on the
Yamaha, and the lower frequencies appeared giving the whole thing a
fuller range.

As explained above, they aren't. But you do need to remove them to
bi-amp as you're doing.

I realize this is far from ideal. I never expected to use the Dared to
power any speaker. But I figured since the B&Ws permit bi-amping why
not try it to see if I can get the fullest sound out of them? Also I
do have a couple of inexpensive SS receivers I could use for
bi-amping, given a proper control unit, but the Dared is my first
experiment with tubes, so why not see what *that's* all about as well?

Why not indeed? But until you solve the volume problem, you won't
really know what the tubes are doing for you.

Andy, your DARED is a fairly low power unit, but it has more than sufficient
power to handle the tweeters in your CM2's. In fact, I doubt the tweeters
in the CM2's can handle the full power of the DARED. Typically tweeters
consume 5% to 7% of the audio power.

Nevertheless, there could still be a problem with the DARED and it could
damage your tweeters. What causes most of the blown tweeters is clipping
and the resulting distortion. Clipping occurs when the audio signal is so
large that it exceeds the rail voltages ... anywhere in the power amp.

I realize this is confusing. My amp has plenty of power, but it could still
damage my speakers???

Problem is power is a measure of voltage and current. Clipping is caused by
running out of just ... voltage.

Fortunately, Andy, there is a very simple solution. Don't send the lowest
frequencies to the DARED. Set the bass tone control all the way OFF and you
will create enormous headroom within the DARED. To see how this works read:

I'm going to save the AK forum for later--I took a look and saw how
involved the discussion was;-)

By bass control, do you mean the one on the pre-amp?

Won't that also reduce bass tone to the Yamaha?

Thanks for all of the information. Seeing it focused on my particular
situation really helps to illuminate the bi-amping issue;-)

Andy Katz

[Jerry]

Andy Katz wrote on 9/24/2006:

Bob, is right it works, but chances are the audio signal is out of phase
on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most likely
180 degrees out-of-phase with each other. To get trhe signals back in
phase:

1. use pre-out for both power amps
2. sent the TAPE OUTPUT into the AUX on the Yamaha and run through the
tone
control amp to get the signals back in phase

Unfortunately, this just gets the signals phased correctly into the power
amps. Since we are talking different technologies here, these amps could
be
reversing the phase again.

Hmmm. Okay. Suppose I use an RCA splitter to connect both amps to the
same input?

Well, it depends upon where you want to connect to these amps.

It's often the same whether you take the TAPE OUTPUT or split the input
using a "Y". Point is the audio signal often gets reversed in the tone
control stage, but Andy, this is really a minor issue. Even if the audio
signals were 180 degrees out of phase, there is a very good chance that you
cannot hear the difference.

Andy, your DARED is a fairly low power unit, but it has more than
sufficient
power to handle the tweeters in your CM2's. In fact, I doubt the
tweeters
in the CM2's can handle the full power of the DARED. Typically tweeters
consume 5% to 7% of the audio power.

Nevertheless, there could still be a problem with the DARED and it could
damage your tweeters. What causes most of the blown tweeters is clipping
and the resulting distortion. Clipping occurs when the audio signal is
so
large that it exceeds the rail voltages ... anywhere in the power amp.

I realize this is confusing. My amp has plenty of power, but it could
still
damage my speakers???

Problem is power is a measure of voltage and current. Clipping is caused
by
running out of just ... voltage.

Fortunately, Andy, there is a very simple solution. Don't send the
lowest
frequencies to the DARED. Set the bass tone control all the way OFF and
you
will create enormous headroom within the DARED. To see how this works
read:

I'm going to save the AK forum for later--I took a look and saw how
involved the discussion was;-)

By bass control, do you mean the one on the pre-amp?

Won't that also reduce bass tone to the Yamaha?

Yes, and that is the issue.

In order to create "head room" in your low power DARED amp, you must remove
the fundamentals from the audio signal. The bass tone control turned full
OFF in your pre-amp will do this. On the other hand, you need the
fundamentals for the Yamaha, so taking the audio signal at the TAPE OUT
achieves this.

Now, to maintain phase you really want to input this audio signal into the
Aux (or TAPE IN) input on the Yamaha. Since the signal then goes trough the
tone control amp in the Yamaha, it maintains the proper phase relationship.
Further, you might be able to reduce the treble tone control in the Yamaha
and achieve a head room gain there as well. Now, the gain in this amp is
NOT as significant as in the DARED and you might actually may need some high
frequency for the low frequency driver.

Andy, what you really want to do is gain head room in the DARED and then let
it handle the high frequencies.

Good luck!

Jerry

[Jerry]

bob wrote on 9/24/2006:

Jerry wrote:

Bob, is right it works, but chances are the audio signal is out of phase
on
each power amp. When you compare the signal onTAPE OUTPUT going to the
Yamaha to the signal on pre-out going to the Dared , they are most
likely
180 degrees out-of-phase with each other.

Hadn't thought of phase. I did wonder whether there would be some
impedance problem driving two amps, one of them a frou-frou tube
design, out of a single set of pre-out jacks. Not saying, just asking.

Bob, the input to most power amps is fairly high impedance. That is, the
amps are looking for an audio voltage signal and don't require much in the
way of current.

So using "Y" or splittng signals is rarely a problem.

Except that, if he takes your advice above and runs both amps out of
his pre-out jacks, then this will also affect the bass response of the
woofer. Youar approach would only work for him if he ran the woofer amp
off the tape out jacks (with phase problems noted), which aren't
affected by the tone controls on the preamp.

Actually, Bob, the better solution that keeps the phase AND allows the
separation of fundamentals from harmonics is to send the TAPE OUT to either
the AUX input or TAPE input. This way the audio signal in both the pre-amp
and the Yamaha gets "flipped" in the tone control circuits. So, phase is
maintained as the audio signal enters the power amps. What no one knows is
whether the audio signal exiting the power amps is still in phase.

Bob, we'd need circuit diagrams for both amps to figure this out or you can
physically see the phase relationship on a dual trace scope.

To see how this works read:

http://audiokarma.org/forums/showthread.php?t=81094

You could post this on a thousand different Web sites, Jerry, and you'd
still be a minority of one!

Well, Bob, I'm no longer a "minority of one". Of course you can always tell
Toasted Almond that he should NOT be passively bi-amping his AR-9's, but I
doubt he'd listen to you:

http://audiokarma.org/forums/showpos...5&postcount=16

Further, this technique of using tone controls to gain headroom is the
perfect solution for Andy. Andy wants to use his high quality, low power
tube amp to drive the tweeters on his CM2s. Passive bi-amping plus removing
the fundmentals is the perfect solution.

Bob, if you have a better solution, please share it with us.

Regards,
Jerry

[Jerry]

wrote in message
...
Jerry wrote:
Clipping is caused by running out of just ... voltage.

That would be "voltage" or voltage limiting. It's also quite
possible to run into "current" clipping as well, better known
as "current limiting," reached when you have hit the current
capacity of the amplifier.

Well, I think of clipping as when the audio signal exceeds the rail voltages
anywhere in the pre or power amp.

As for "current limiting", Dick, do you really think there is any chance of
that happening when driving a tweeter?

Regards,
Jerry

[Walt]

Andy Katz wrote:

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

The latter. See http://sound.westhost.com/bi-amp.htm

//Walt

[bob]

Jerry wrote:

Further, you might be able to reduce the treble tone control in the Yamaha
and achieve a head room gain there as well. Now, the gain in this amp is
NOT as significant as in the DARED and you might actually may need some high
frequency for the low frequency driver.

Given that it's not a "low-frequency driver," but a midrange/woofer
with a 4kHz crossover point, this is almost certainly the case. That's
why it would be a very bad idea. Also, pointless, since he doesn't have
a headroom problem at all.

If you insist on using crappy, underpowered amps, then drastic measures
like this may be necessary. But with decent modern gear, they can only
cause problems. His Yamaha is certainly decent, and if the little tube
amp can drive the entire speaker, he can't be facing a headroom problem
when it's only driving the tweeter.

Do what you want in your own system, Jerry, but you're giving him bad
advice.

bob

[bob]

Walt wrote:
Andy Katz wrote:

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

The latter. See http://sound.westhost.com/bi-amp.htm

Not necessarily. If he does this right, he'll have a small tube amp,
with a certain tonal color, driving his tweeters, and he might like
that sound. There's no *power* reason to do what he's doing, which is
the point of the site yo've posted. But he said he wanted to experiment
with tubes, and this is a legitimate way to do it.

bob

[Jerry]

bob wrote on 9/25/2006:

Jerry wrote:

Further, you might be able to reduce the treble tone control in the
Yamaha
and achieve a head room gain there as well. Now, the gain in this amp
is
NOT as significant as in the DARED and you might actually may need some
high
frequency for the low frequency driver.

Given that it's not a "low-frequency driver," but a midrange/woofer
with a 4kHz crossover point, this is almost certainly the case. That's
why it would be a very bad idea. Also, pointless, since he doesn't have
a headroom problem at all.

True, but in all fairness I pointed out that "you might actually need some
high frequency for..."

Please remember, Bob, that the center frequency on many treble controls is
in the 15k to 20kHz range. How much of an impact those controls will have
down at 4kHz is debatable.

If you insist on using crappy, underpowered amps, then drastic measures
like this may be necessary. But with decent modern gear, they can only
cause problems. His Yamaha is certainly decent, and if the little tube
amp can drive the entire speaker, he can't be facing a headroom problem
when it's only driving the tweeter.

Do what you want in your own system, Jerry, but you're giving him bad
advice.

bob

Bob, I don't think the Dared MP-5 is a "crappy amp". It's a fairly high
quality amp, but was designed to power headphones. Nevertheless, it will do
an outstanding job powering the tweeters in these CRM's.

There are just a few things Andy needs to do to insure these little amps
don't cause long terms problems. Nothing really much, however. Further, I
applaud Andy for looking for creative ways to use his high quality amp.

Experimentation, IMO, should be encouraged. That's what a hobby is all
about.

Regards,
Jerry

[Andy Katz]

On 26 Sep 2006 01:10:29 GMT, "bob" wrote:

Walt wrote:
Andy Katz wrote:

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

The latter. See http://sound.westhost.com/bi-amp.htm

Not necessarily. If he does this right, he'll have a small tube amp,
with a certain tonal color, driving his tweeters, and he might like
that sound. There's no *power* reason to do what he's doing, which is
the point of the site yo've posted. But he said he wanted to experiment
with tubes, and this is a legitimate way to do it.

Thanks, Bob.

I can't tell you how much I appreciate everyone's advice.

I stopped by Circuit City to buy an RCA splitter, but I was told that
this would mess up the signal, what I really needed was a switcher. So
I went to Radio Shack. They had the switcher, but not one that would
permit simultaneous output from a single set of RCA jacks.

My pre-amp has, as I wrote, two sets of pre-outs, one fixed the other
variable, the latter intended for use in normal pre-amp functions,
while the former is likely intended for headphone amps and the sort.

I don't see any way to split the output from the variable out that
would permit the single pre-amp to control power from both amps.

Right now, in fact, the way I'm set up I'm only using the pre-amp for
the Yamaha's output. I have the Dared connected directly to the cd
player's multi-channel out (the first set of red and white outs next
to the stereo outs, which are, naturally, hooked up to pre-amp). I
figured why run the signal through the pre-amp when I was only using
the cd player right now?

Andy Katz

[Andy Katz]

On 25 Sep 2006 23:15:40 GMT, Walt wrote:

Andy Katz wrote:

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

The latter. See http://sound.westhost.com/bi-amp.htm

Thank you very much, Walt.

I think I'd seen that article before. It's usually at the point where
the author talks about "saving the parts [from the disassembled
crossover]" that I tune out. I paid what for me was a lot for these
speakers and the idea of tinkering around inside is pretty
disconcerting.

But maybe it would be silly to have paid so much and not enjoy the
best possible sound quality?

It definitely deserves a second thought;-)

Andy Katz

[Andy Katz]

On 26 Sep 2006 03:45:20 GMT, "Jerry" wrote:

bob wrote on 9/25/2006:

Jerry wrote:

Further, you might be able to reduce the treble tone control in the
Yamaha
and achieve a head room gain there as well. Now, the gain in this amp
is
NOT as significant as in the DARED and you might actually may need some
high
frequency for the low frequency driver.

Given that it's not a "low-frequency driver," but a midrange/woofer
with a 4kHz crossover point, this is almost certainly the case. That's
why it would be a very bad idea. Also, pointless, since he doesn't have
a headroom problem at all.

True, but in all fairness I pointed out that "you might actually need some
high frequency for..."

Please remember, Bob, that the center frequency on many treble controls is
in the 15k to 20kHz range. How much of an impact those controls will have
down at 4kHz is debatable.

If you insist on using crappy, underpowered amps, then drastic measures
like this may be necessary. But with decent modern gear, they can only
cause problems. His Yamaha is certainly decent, and if the little tube
amp can drive the entire speaker, he can't be facing a headroom problem
when it's only driving the tweeter.

Do what you want in your own system, Jerry, but you're giving him bad
advice.

bob

Bob, I don't think the Dared MP-5 is a "crappy amp". It's a fairly high
quality amp, but was designed to power headphones. Nevertheless, it will do
an outstanding job powering the tweeters in these CRM's.

There are just a few things Andy needs to do to insure these little amps
don't cause long terms problems. Nothing really much, however. Further, I
applaud Andy for looking for creative ways to use his high quality amp.

Thanks, Jerry. I appreciate the caution about possibly doing long-term
damage to the tweeters by using the amp without matching its power
capabilities. I'm going to explore disconnecting the real passive
crossover (so why do they have those external straps, then?).

But I'm also looking for a way to coordinate the signal power to both
amps, my current pre-amp doesn't seem up to it. Does it need to be
replaced, or is there another way?

I see now that simply splitting the RCA variable pre-out jack set
won't work.

Experimentation, IMO, should be encouraged. That's what a hobby is all
about.

;-)

Andy Katz

[bob]

Jerry wrote:

Please remember, Bob, that the center frequency on many treble controls is
in the 15k to 20kHz range. How much of an impact those controls will have
down at 4kHz is debatable.

I seriously doubt there are too many treble controls centered at 20kHz.
10kHz is more like it. And you are forgetting--once again, though it's
been explained to you before--that a crossover filter is not a brick
wall. That mid-woofer is going to be active a good octave or more above
that frequency. And a treble control centered at 10kHz is going to have
an impact at least a octave down from that. See the problem?

If you insist on using crappy, underpowered amps, then drastic measures
like this may be necessary. But with decent modern gear, they can only
cause problems. His Yamaha is certainly decent, and if the little tube
amp can drive the entire speaker, he can't be facing a headroom problem
when it's only driving the tweeter.

Do what you want in your own system, Jerry, but you're giving him bad
advice.

bob

Bob, I don't think the Dared MP-5 is a "crappy amp".

I wasn't talking about his amp, Jerry.

It's a fairly high
quality amp, but was designed to power headphones.

"High quality" is in the eye of the beholder, but this is not just a
headphone amp. It is specifically marketed to drive speakers. Whether
it can really do so is open to question, given the lack of published
specs. But it seems to be sufficient for Andy's purposes.

bob

[bob]

Andy Katz wrote:

Thanks, Jerry. I appreciate the caution about possibly doing long-term
damage to the tweeters by using the amp without matching its power
capabilities.

Except that you're almost certainly not doing that. You are, on the
other hand, about to embark on a dangerous exercise to avoid this
nonexistent problem...

I'm going to explore disconnecting the real passive
crossover (so why do they have those external straps, then?).

Whoa, there, cowboy! Do you understand what this means? This means
going inside your speaker, disconnecting the crosover, and buying an
external electronic crossover to do the job. Are you really up for
that???

But I'm also looking for a way to coordinate the signal power to both
amps, my current pre-amp doesn't seem up to it. Does it need to be
replaced, or is there another way?

Why not?

I see now that simply splitting the RCA variable pre-out jack set
won't work.

Why not?

bob

[bob]

Andy Katz wrote:

I stopped by Circuit City to buy an RCA splitter, but I was told that
this would mess up the signal, what I really needed was a switcher. So
I went to Radio Shack. They had the switcher, but not one that would
permit simultaneous output from a single set of RCA jacks.

That's because the last thing you want in this case is a switcher.
Which should tell you that the boob you talked to at CC was just
that--a boob.

My pre-amp has, as I wrote, two sets of pre-outs, one fixed the other
variable, the latter intended for use in normal pre-amp functions,
while the former is likely intended for headphone amps and the sort.

I don't see any way to split the output from the variable out that
would permit the single pre-amp to control power from both amps.

Unless there's an impedance problem (and Jerry says there wouldn't be,
but I'd like someone else's opinion on that), there's no reason you
can't use a splitter. And I seriously doubt that anyone working at
Circuit City even knows what impedance is.

Right now, in fact, the way I'm set up I'm only using the pre-amp for
the Yamaha's output. I have the Dared connected directly to the cd
player's multi-channel out (the first set of red and white outs next
to the stereo outs, which are, naturally, hooked up to pre-amp).

What the hell kind of CD player is that???

Sorry, but it sounds like you're using a *DVD* player, one with a
multichannel DAC. Are you sure you're getting the left and right
stereo signals out of those two jacks, and not some Dolby processed
thing?

I
figured why run the signal through the pre-amp when I was only using
the cd player right now?

I guess, if you know what you're doing. But are you sure you know what
you're doing?

bob

[Harry Lavo]

"Andy Katz" wrote in message
...
On 26 Sep 2006 01:10:29 GMT, "bob" wrote:

Walt wrote:
Andy Katz wrote:

I connected my B&W CM2s to a Dared MP-5. It surprised me by powering
them quite well. Then I thought, why leave well enough alone? My
pre-amp has both a CD and an un-regulated tape out for recording, so
output from the same source can be sent to two amps simultaneously. So
I removed the passive cross-over and ran some 14 gauge from the Dared
to the high range, and the same gauge from the SS amp, a Yamaha AX
570.

I didn't have a chance to do more than test it out: Straight, No
Chaser sounded really full on SACD (souce is the Pioneer all-in-one).
Needless to say this requires tweaking both amps separately. But if
one takes the time to balance the high and low frequencies, does this
sound like a valid bi-amping method ... or am I just spinning my sonic
wheels here?

The latter. See http://sound.westhost.com/bi-amp.htm

Not necessarily. If he does this right, he'll have a small tube amp,
with a certain tonal color, driving his tweeters, and he might like
that sound. There's no *power* reason to do what he's doing, which is
the point of the site yo've posted. But he said he wanted to experiment
with tubes, and this is a legitimate way to do it.

Thanks, Bob.

I can't tell you how much I appreciate everyone's advice.

I stopped by Circuit City to buy an RCA splitter, but I was told that
this would mess up the signal, what I really needed was a switcher. So
I went to Radio Shack. They had the switcher, but not one that would
permit simultaneous output from a single set of RCA jacks.

My pre-amp has, as I wrote, two sets of pre-outs, one fixed the other
variable, the latter intended for use in normal pre-amp functions,
while the former is likely intended for headphone amps and the sort.

I don't see any way to split the output from the variable out that
would permit the single pre-amp to control power from both amps.

Right now, in fact, the way I'm set up I'm only using the pre-amp for
the Yamaha's output. I have the Dared connected directly to the cd
player's multi-channel out (the first set of red and white outs next
to the stereo outs, which are, naturally, hooked up to pre-amp). I
figured why run the signal through the pre-amp when I was only using
the cd player right now?

Andy -

Go back to radio shack and ignore whatever the salesman says.....just find
an RCA splitter: female to (2) female pairs. This can be in the form of a
"Y" cable, or a solid rectangular adaptor with one pair on one end and two
pair on the other. If you can't find female-female, buy female-male and
use a gender changer. Using a splitter on you preamp output is going to
pose no problems at all for either the preamp or the amplifiers themselves.

[Andy Katz]

On 26 Sep 2006 23:52:57 GMT, "bob" wrote:

Andy Katz wrote:

Thanks, Jerry. I appreciate the caution about possibly doing long-term
damage to the tweeters by using the amp without matching its power
capabilities.

Except that you're almost certainly not doing that. You are, on the
other hand, about to embark on a dangerous exercise to avoid this
nonexistent problem...

I'm going to explore disconnecting the real passive
crossover (so why do they have those external straps, then?).

Whoa, there, cowboy! Do you understand what this means? This means
going inside your speaker, disconnecting the crosover, and buying an
external electronic crossover to do the job. Are you really up for
that???

Most emphatically not, Bob;-)

I got carried away with the cited article's enthusiasm and the obvious
benefits of portioning out the available power. On sober reflection,
however, no, I'm not going to disassemble my loudspeakers.

Seems a shame, however, that high-end loudspeakers often come with a
feature that tempts us thus.

But I'm also looking for a way to coordinate the signal power to both
amps, my current pre-amp doesn't seem up to it. Does it need to be
replaced, or is there another way?

Why not?

I see now that simply splitting the RCA variable pre-out jack set
won't work.

Why not?

Okay. Thanks. I read the other comments, yours and Harry's. Perhaps
the salesman misunderstood the application, or was speaking out his
behind.

I'll try it tomorrow. Even if I don't care for the result I can still
use the splitter for another application.

Thanks for the encouragement ... and the sanity check;-)

Andy Katz

[Andy Katz]

On 27 Sep 2006 02:16:35 GMT, "bob" wrote:

Andy Katz wrote:

I stopped by Circuit City to buy an RCA splitter, but I was told that
this would mess up the signal, what I really needed was a switcher. So
I went to Radio Shack. They had the switcher, but not one that would
permit simultaneous output from a single set of RCA jacks.

That's because the last thing you want in this case is a switcher.
Which should tell you that the boob you talked to at CC was just
that--a boob.

Okay. I'm it was just *my* impression;-)

My pre-amp has, as I wrote, two sets of pre-outs, one fixed the other
variable, the latter intended for use in normal pre-amp functions,
while the former is likely intended for headphone amps and the sort.

I don't see any way to split the output from the variable out that
would permit the single pre-amp to control power from both amps.

Unless there's an impedance problem (and Jerry says there wouldn't be,
but I'd like someone else's opinion on that), there's no reason you
can't use a splitter. And I seriously doubt that anyone working at
Circuit City even knows what impedance is.

Right now, in fact, the way I'm set up I'm only using the pre-amp for
the Yamaha's output. I have the Dared connected directly to the cd
player's multi-channel out (the first set of red and white outs next
to the stereo outs, which are, naturally, hooked up to pre-amp).

What the hell kind of CD player is that???

Sorry, but it sounds like you're using a *DVD* player, one with a
multichannel DAC. Are you sure you're getting the left and right
stereo signals out of those two jacks, and not some Dolby processed
thing?

Oh. You're right. It is a DVD (all-in-one sort). I'm really not sure
what signal I'm getting out of the multi-jacks, but it won't matter
because I'll re-connect the tube amp to the variable pre-out on the
pre-amp and that should render that question moot.
I
figured why run the signal through the pre-amp when I was only using
the cd player right now?

I guess, if you know what you're doing. But are you sure you know what
you're doing?

Not at all;-)

That's why I appreciate everyone's time and input.

If I do manage to split the signal evenly from the variable pre-out,
how should I set the volume on the tube amp (remembering there's no
way to de-couple it the way the Yamaha's been decoupled)?

Andy Katz

[bob]

Andy Katz wrote:
On 26 Sep 2006 23:52:57 GMT, "bob" wrote:

Whoa, there, cowboy! Do you understand what this means? This means
going inside your speaker, disconnecting the crosover, and buying an
external electronic crossover to do the job. Are you really up for
that???

Most emphatically not, Bob;-)

I got carried away with the cited article's enthusiasm and the obvious
benefits of portioning out the available power. On sober reflection,
however, no, I'm not going to disassemble my loudspeakers.

Seems a shame, however, that high-end loudspeakers often come with a
feature that tempts us thus.

If you've got to pry open a speaker cabinet to do something, I wouldn't
call that something a "feature."

bob

[Jerry]

bob wrote on 9/26/2006:

Jerry wrote:

Please remember, Bob, that the center frequency on many treble controls
is
in the 15k to 20kHz range. How much of an impact those controls will
have
down at 4kHz is debatable.

I seriously doubt there are too many treble controls centered at 20kHz.
10kHz is more like it.

Turns out, mine is!! Here is the spec:

Treble Control: Dual tandem control. Fully clockwise provides 14 db boost
at 20 kHz. Full counterclockwise provides 14 db cut at 20 kHz

Bass Control: Dual tandem control. Fully clockwise provides 15 db boost at
20 Hz. Full counterclockwise provides 18 db cut at 20 Hz

But then again, Heath always did things right!!

And you are forgetting--once again, though it's
been explained to you before--that a crossover filter is not a brick
wall. That mid-woofer is going to be active a good octave or more above
that frequency. And a treble control centered at 10kHz is going to have
an impact at least a octave down from that. See the problem?

OK, so let's not speculate and let's do the math. At 10 kHz we should be
down 24 db and at 5 kHz we should be down 36 db.

Down 36 db! Do you really think you could hear this, Bob?

Regards,
Jerry

[Jerry]

Andy Katz wrote on 9/27/2006:


If I do manage to split the signal evenly from the variable pre-out,
how should I set the volume on the tube amp (remembering there's no
way to de-couple it the way the Yamaha's been decoupled)?

Andy Katz

Andy, you are making this far more complicated than it has to be.

In order to protect your tweeters from clipping damage, you need to created
headroom in your low power Dared. The ONLY way to create headroom in the
DARED is to remove the bass signal going into the DARED. The only way you
can do that is via your pre-amp. You turn the bass tone control all the way
OFF. Route the pre-out to the DARED input. Connect the DARED output to
just the tweeter terminals on the CM2's with the STRAP REMOVED.

Never, ever leave that strap in place with two amps connected to your
speakers .... if you do you will fry EVERYTHING.

Now you require a full signal for the woofer in the CM2 and this signal must
come from the Yamaha. You cannot get that full signal from the pre-amp.
The pre-amp's signal has the bass line removed. So you must get a signal
prior to the pre-amp and you have the following choices:

1. use the "y" cable that Harry mentioned on the output of the CD and route
to TAPE IN on the Yamaha

2. use any audio cables from the TAPE OUT on the pre-amp into TAPE IN on
the Yamaha

Set your tone controls on the Yamaha to 12 o'clock and connect the output to
the woofer terminals on the CM2

Now, set the volume control on the pre-amp AND the Yamaha to the LOWEST
level, start your cd and slowly raise the level on the pre-amp. Once you
hear music, slowly raise the level on the Yamaha. Very quickly, Andy,
you'll learn how to manage these two volume controls.... I do it every day.
The balance of highs to lows is so great and granular that it's pretty hard
to get way off.

Now, listen to some of your favorite music and become familiar with the
sound of your tube amp on top with your ss amp below.

Shut it down replace the strap and drive everything with the Yamaha alone.
Only you can tell, Andy, whether the sound of your bi-amp (mixing tube and
solid state) is superior to your single solid state amp.

Good luck!

Jerry

[Walt]

Harry Lavo wrote:

Go back to radio shack and ignore whatever the salesman says.....just find
an RCA splitter: female to (2) female pairs. This can be in the form of a
"Y" cable, or a solid rectangular adaptor with one pair on one end and two
pair on the other. If you can't find female-female, buy female-male and
use a gender changer. Using a splitter on you preamp output is going to
pose no problems at all for either the preamp or the amplifiers themselves.

Agree completely. The simple rule of thumb is that you can always* use
a Y cable to split an output to drive two inputs, but you should never
use a Y cable to combine two outputs into one input.

//Walt

*for most values of always.