My current system is a CAL CL-2500DVD fed into a custom active
crossover with volume and source controls, fed into a Classe CAV-75
6-channel amplifier, directly driving the drivers of a pair of 3-way
speakers (crossed over at 300 and 3000 Hz).

I need 6 channels of amplification, total.

I occasionally wonder if there is anything to be gained from upgrading
the power amplifier to the Classe CAV-150 for twice the rated power, or
maybe a different brand of amplifier. I know that I like the sound of
Counterpoint amps, but the price of a set of upgraded amps (two NP-12s
and an NP-220) is really beyond what I want to spend and the
non-upgraded examples if the SA-12 I've had were showing signs of age
(poor matching of overall gain, leaking electrolytic power supply
capacitors). Looking at the used market, it seems that a pair of
Aragon 8008x3 amps would fit my budget, or a new Aragon 2007.

Has anyone been able to compare the old 8008 series with the new 200X
series?

Are there any other amplifiers I ought to consider? The last time I
read this newsgroup, one or more people were singing the praises of a
not-too-expensive Yamaha power amp. I think Stewart was one of them.
Should I look into that? Are there any other high-quality/low-prestige
amps that have shown up on the scene?

I'm also contemplating just building a power stage into the custom
crossover. Earlier in the year I built an integrated amp using some
National Semiconductor IC audio power amps to use in my bedroom. Last
weekend, I brought the amp over to a friend's house and used it to
drive his Vandersteen 3A Signatures. It sounded surprisingly good!
And that's with a low-power switching power supply which results in
voltage-limited power of about 32 Watts.

Cheers,
John Stimson

John Stimson wrote:

Are there any other amplifiers I ought to consider?

Last year I fried the outputs on my old B&K amp for
about the 3rd time. Now that you can't get the output
devices for that amp anymore (unless you buy 'em from
B&K for $21 each), it was time to look at something else.

I like the sound of a good MOSFET amp. As I was moving
to the Linkwitz Orion loudspeaker, which needs 8 channels
of amplification, I had to figure out something pretty
fast, or it was going to get real expensive. I ended up
going with Hafler P1000 power amps, which are a pro grade
amp. They're all of 50 watts per channel, but in a
tri-amped setting, they're actually plenty of power.

Being pro grade, they handle all kinds of possible
signal abuse. They also rack mount and are only 1U high.
I took my time and picked 'em up on EBay for between
$125 - $150. You can see them at:

http://www.button.com/family/photos/russ/orion/

Siegfried Linkwitz came over to the house after the
Orions got built and thought the project had come out
fine. He likes the Hafler amps, even though he recommends
the ATI multi-amp. His primary amp criteria is that all
8 channels have identical voltage sensitivity and gain.

Since you're going to be tri-amping, you might consider
scoring some Hafler pro grade amps off of EBay. What makes
an amp pro grade is that it is intended to handle more
abuse, both physical and electrical.

Russ Button

"John Stimson" wrote in message
...
My current system is a CAL CL-2500DVD fed into a custom active
crossover with volume and source controls, fed into a Classe CAV-75
6-channel amplifier, directly driving the drivers of a pair of 3-way
speakers (crossed over at 300 and 3000 Hz).

I need 6 channels of amplification, total.

I occasionally wonder if there is anything to be gained from upgrading
the power amplifier to the Classe CAV-150 for twice the rated power, or
maybe a different brand of amplifier.

If yu double the wattage you could get increased spl's. 50% more power
means 3 db increase in SPL.

I know that I like the sound of
Counterpoint amps, but the price of a set of upgraded amps (two NP-12s
and an NP-220) is really beyond what I want to spend and the
non-upgraded examples if the SA-12 I've had were showing signs of age
(poor matching of overall gain, leaking electrolytic power supply
capacitors). Looking at the used market, it seems that a pair of
Aragon 8008x3 amps would fit my budget, or a new Aragon 2007.

Or you could just repair what you have.

John Stimson wrote:
I need 6 channels of amplification, total.

In the Yamaha range, the 650 and the models above have 7 channels.

http://www.yamaha-audio.co.uk/pdfs/manuals/RXV650.pdf
Other manuals at:
http://www.yamaha-audio.co.uk/downloads/manuals.php

This model costs EUR 369 at http://www.technikdirekt.de/
On this page it is not possible to keep bookmarks, but if you search
by the catalogue number you will get directly to the page:

638475 RX-V 650 black
638468 RX-V 650 titanium
638517 RX-V 750 black
638496 RX-V 750 titanium

Are there any other amplifiers I ought to consider?

The RX-V 1500 and RX-V 2500 have a bit more power and a bit less distorsion:

650 7 * 95 W THD 0.06%
750 7 * 100 W THD 0.06%
1500 7 * 120 W THD 0.04%
2500 7 * 130 W THD 0.04%

The last time I
read this newsgroup, one or more people were singing the praises of a
not-too-expensive Yamaha power amp. I think Stewart was one of them.
Should I look into that? Are there any other high-quality/low-prestige
amps that have shown up on the scene?

Pioneer, Denon, etc.

--
http://www.mat.uc.pt/~rps/

..pt is Portugal| `Whom the gods love die young'-Menander (342-292 BC)
Europe | Villeneuve 50-82, Toivonen 56-86, Senna 60-94

Russ,

Thanks for the suggestion to look at the Hafler P1000 amps. It looks
like I could get set up with four of them (2 bridged for the woofers)
for less than the Classe amp cost me. How do you think the sound
quality would compare?

If yu double the wattage you could get increased spl's. 50% more power
means 3 db increase in SPL.

I understand that. I'm more interested in any differences in sound
quality that might exist between the CAV-75 and CAV-150.

Or you could just repair what you have.

Oh, I replaced all the electrolytic capacitors on the Counterpoint amps
before I decided to sell them off. Some of the other features like the
gain matching and rustling were beyond my ability to diagnose, and
would probably require a full rebuild with new components to fully work
out. I'm quite happy with the fully functional Classe CAV-75 that
replaced them; I'm just asking if anyone thinks I could do even better
with something else.

Rui Pedro Mendes Salgueiro wrote:



John Stimson wrote:
I need 6 channels of amplification, total.

In the Yamaha range, the 650 and the models above have 7 channels.


I think there is a bit of confusion here. : )
What you folks outside the U.S.refer to as an "amplifier" (tuner, preamp, power
amp in one unit), we refer to as a "receiver". What John is referring to when
he says "amplifier", means that he needs just a power amp, and has no need for
the preamp and tuner (he uses seperates).

Hope this clears up any confusion. : )

Jeff

UnionPac2004 wrote:

Rui Pedro Mendes Salgueiro wrote:



John Stimson wrote:
I need 6 channels of amplification, total.

In the Yamaha range, the 650 and the models above have 7 channels.


I think there is a bit of confusion here. : )
What you folks outside the U.S.refer to as an "amplifier" (tuner, preamp, power
amp in one unit), we refer to as a "receiver". What John is referring to when
he says "amplifier", means that he needs just a power amp, and has no need for
the preamp and tuner (he uses seperates).

Hope this clears up any confusion. : )

Jeff

Actually there is no confusion. A receiver can also be used as an
amplifier, so the advice given was a reasonable one.

Not when you're looking to replace a Classe CAV-75 with something
better. None of the amplifier sections of the receivers mentioned
would even remotely be considered an upgrade. So it was either
confusion, or bad advice, in this context, IMO. Take your pick.
Jeff (aka,UnionPac2004)

John Stimson wrote:
My current system is a CAL CL-2500DVD fed into a custom active
crossover with volume and source controls, fed into a Classe CAV-75
6-channel amplifier, directly driving the drivers of a pair of 3-way
speakers (crossed over at 300 and 3000 Hz).

John, maybe it will be better not to connect a bigger amp to your mid and
treble sections as they might blow the speakers. I would recommend an
additional 2x200-300W for the bass channel though, as those drivers are more
rugged and probably will need more power anyway as the efficiency is usually
a bit lower. You should write more about the connected speakers to verify
this assumption.
--
ciao Ban
Bordighera, Italy

UnionPac2004 wrote:
Rui Pedro Mendes Salgueiro wrote:
John Stimson wrote:
I need 6 channels of amplification, total.
In the Yamaha range, the 650 and the models above have 7 channels.

What John is referring to when he says "amplifier", means that
he needs just a power amp, and has no need for the preamp and
tuner (he uses seperates).

These receivers:

1 - can be used as 7-channel power amplifiers by using the
multi-channel analogue inputs (ok, they have a volume control
but the tone controls are bypassed when using the multi-channel
analogue inputs);

2 - are cheaper than a separate power amplifier; (which means that
the preamp and the tuner are effectively free.)

3 - and anyway the sound quality is the same (see all the long
discussions about "amplifier sound", DBTs, etc.). In fact John
asked about Yamaha amplifiers because of a post mentioning
them, which was probably the story about the store owner who
was unable to hear a difference between a normal Yamaha
amplifier and his expensive monoblock amplifiers in a DBT.

--
http://www.mat.uc.pt/~rps/

..pt is Portugal| `Whom the gods love die young'-Menander (342-292 BC)
Europe | Villeneuve 50-82, Toivonen 56-86, Senna 60-94

wrote:

Not when you're looking to replace a Classe CAV-75 with something
better. None of the amplifier sections of the receivers mentioned
would even remotely be considered an upgrade. So it was either
confusion, or bad advice, in this context, IMO. Take your pick.
Jeff (aka,UnionPac2004)

No, not really. It's an advice based on value, i.e., an attractive cost
for a given level of performance. Did you miss the part when the OP said
that an integrated amp based on National IC's sounded surprisingly good?
Depending on the power needed and the load presented, the Yamahas can be
very good. If someone wants 6 channels of amp, I would think that it is
reasonable to suggest listening to a good receiver, or perhaps using the
receiver to drive the surround channels and another amplifer for the mains.

Rui Pedro Mendes Salgueiro wrote:

wrote:
Not when you're looking to replace a Classe CAV-75 with something
better.

True. I had not searched for info on that amplifier. Now that I found it:


Well, I shouldn't have referred to your advice as "bad". Sorry for that. What
I should have said was that I found your advice, IMO, unusual. I didn't see
the point in paying for a preamp section, and a tuner section, when all the OP
was looking for was power amplification.



But, as it has been mentioned here lots of times, most probably one
can't hear the difference between those impressive numbers and the
somewhat less impressive Yamaha numbers:


You are probably correct. Power wise, do you know if Yamaha overinflates their
power specs, like many of their competitors do? Or are their figures honest
ones? I've always liked the Yamaha gear I've been exposed to in the past, but
don't have as much experience with their newest pieces...

None of the amplifier sections of the receivers mentioned
would even remotely be considered an upgrade.

Well, they have more power which might be a criterium.


Point taken. I don't recall all the specifics of the original post right now.
But if more power was a primary goal, then perhaps the Yammies would be an
upgrade, IF their power specs are honest ones.

Jeff (aka 1shado1)

Chung wrote:



wrote:

Not when you're looking to replace a Classe CAV-75 with something
better. None of the amplifier sections of the receivers mentioned
would even remotely be considered an upgrade. So it was either
confusion, or bad advice, in this context, IMO. Take your pick.
Jeff (aka,UnionPac2004)

No, not really. It's an advice based on value, i.e., an attractive cost
for a given level of performance. Did you miss the part when the OP said
that an integrated amp based on National IC's sounded surprisingly good?
Depending on the power needed and the load presented, the Yamahas can be
very good. If someone wants 6 channels of amp, I would think that it is
reasonable to suggest listening to a good receiver, or perhaps using the
receiver to drive the surround channels and another amplifer for the mains.


Perhaps the term "bad" advice WAS inappropriate. IMO it was somewhat unusual
advice. I didn't see the point in paying for a tuner and preamp section when
one wasn't needed.

Yes, I had forgotten about the mentioned integrated based on National IC's
sounding good. My bad.

You are right, it was a reasonable suggestion, having reminded me about the
abovementioned integrated. Although it's probably not the route I would take
(just personal preference).

Jeff (aka 1shado1)

UnionPac2004 wrote:
Chung wrote:



wrote:

Not when you're looking to replace a Classe CAV-75 with something
better. None of the amplifier sections of the receivers mentioned
would even remotely be considered an upgrade. So it was either
confusion, or bad advice, in this context, IMO. Take your pick.
Jeff (aka,UnionPac2004)

No, not really. It's an advice based on value, i.e., an attractive cost
for a given level of performance. Did you miss the part when the OP said
that an integrated amp based on National IC's sounded surprisingly good?
Depending on the power needed and the load presented, the Yamahas can be
very good. If someone wants 6 channels of amp, I would think that it is
reasonable to suggest listening to a good receiver, or perhaps using the
receiver to drive the surround channels and another amplifer for the mains.


Perhaps the term "bad" advice WAS inappropriate. IMO it was somewhat unusual
advice. I didn't see the point in paying for a tuner and preamp section when
one wasn't needed.

However, the economy of scale has to be considered, and a receiver may
very well cost less than an integrated amp or a power amp with the same
amplifier section.

UnionPac2004 wrote:
Rui Pedro Mendes Salgueiro wrote:
wrote:
Not when you're looking to replace a Classe CAV-75 with something
better.

I didn't see the point in paying for a preamp section, and a tuner
section, when all the OP was looking for was power amplification.

Those are "free". What I mean here is that the economies of scale
and the reduced margins due to the Yamaha being a mass-market product
are more than the expense of the preamp and tuner sections.

In another context, but similarly, if someone is looking for a
2-channel receiver and "doesn't want to pay for extra channels that
he doesn't need", you can think of those channels as "free", since
the price of a 5 or 6 channel receiver is the same as the 2-channel
receiver (similar power ratings). For instance in the Yamaha range
the Yamaha RX-496 (2 * 75 W) and the RX-V450 (6 * 85 W) have about
the same price ($250).

I suppose the reason for this is, again, economies of scale and maybe
lower margins due to a more competitive market.

Power wise, do you know if Yamaha overinflates their power specs,
like many of their competitors do? Or are their figures honest ones?

It was some time ago that I searched for tests of amplifiers. There
is not much information one can find in the net, but from what I
remember this kind of amplifiers usually have somewhat _more_ power
than claimed by the manufacturer.

For instance, I have here a British magazine (http://www.hi-fiworld.co.uk/
March 2004 issue) and they measured that a Pioneer VSX-AX5I-S,
which Pionner claims produces 7*100 W (into 8 ohms, I suppose) is
in fact capable of 120 W into 8 ohms and 210 W into 4 ohms.

And then, there are many ways of measuring power. For instance the
Yamaha RX-V 750:

Minimum RMS Output Power for Front, Center, Surround, Surround back
20 Hz to 20 kHz, 0.06% THD, 8 ohms 100 W

Maximum Power (EIAJ) [China, Korea and General models]
1 kHz, 10% THD, 8 ohms 140 W

Dynamic Power (IHF) 8/6/4/2 ohms 135/170/200/245 W

DIN Standard Output Power [U.K., Europe and Asia models]
1 kHz, 0.7% THD, 4 ohms 150 W

IEC Output Power [U.K., Europe and Asia models]
1 kHz, 0.06% THD, 8 ohms 110 W

But there is one point: it seems that the power supply doesn't
allow all channels to work at full power continuously. For instance
the Yamaha RX-V 750 is a 7 * 100 W (RMS). But its "Power Consumption"
is given as 400 W/500 VA (USA) or 440 W (rest of the world). So,
either this "Power Consumption" is something other than maximum
(typical or whatever) or you can't get full power from all the
channels at the same time, which would need more than 700 watts
(what is the typical efficiency of this kinf of amplifiers at full power ?)

For the purposes of the original poster (separate channels for each
driver on his speakers) this is probably not important, since it
is unlikely that he would need to supply 100 W to the tweeters
and mid-range drivers.

--
http://www.mat.uc.pt/~rps/

..pt is Portugal| `Whom the gods love die young'-Menander (342-292 BC)
Europe | Villeneuve 50-82, Toivonen 56-86, Senna 60-94

I'd recommend looking at Outlaw Audio. They seem to offer the
best watt per dollar of the larger amplifiers.