[guy25]

I have a pair of B&W 801 series 2 and one speaker's crossover over load and burned (a round orange coil) is this repair able? any information will be very appreciates. I'm living in Chicago. Thanks in advance, guy25

[Trevor Wilson[_3_]]

guy25 wrote:
I have a pair of B&W 801 series 2 and one speaker's crossover over
load and burned (a round orange coil) is this repair able? any
information will be very appreciates. I'm living in Chicago. Thanks
in advance, guy25

**Of course it's repairable. I can't help you with the value of the part,
but it would be simple enough to examine the other speaker and measure the
good part.


--
Trevor Wilson
www.rageaudio.com.au

[Mr.T]

"Trevor Wilson" wrote in message
...
guy25 wrote:
I have a pair of B&W 801 series 2 and one speaker's crossover over
load and burned (a round orange coil) is this repair able? any
information will be very appreciates. I'm living in Chicago. Thanks
in advance, guy25

Have you checked the driver as well?


**Of course it's repairable. I can't help you with the value of the part,
but it would be simple enough to examine the other speaker and measure the
good part.

Sure, if he can actually measure the inductance, which is doubtful if he had
to ask the question in the first place. (wire gauge and coil resistance is
easier of course)
May be easier just to contact B&W or their local agent for spares?


MrT.

[geoff]

guy25 wrote:
I have a pair of B&W 801 series 2 and one speaker's crossover over
load and burned (a round orange coil) is this repair able? any
information will be very appreciates. I'm living in Chicago. Thanks
in advance, guy25

No , it's not repairable. Send the speakers to me.

geoff

[geoff]

geoff wrote:
guy25 wrote:
I have a pair of B&W 801 series 2 and one speaker's crossover over
load and burned (a round orange coil) is this repair able? any
information will be very appreciates. I'm living in Chicago. Thanks
in advance, guy25

No , it's not repairable. Send the speakers to me.

geoff

Actually, of course it is repairable. But given the value of the speakers
would contact B&W for a local service agent, and a source of the genuine
spare part.

geoff

[guy25]

Originally Posted by geoff

geoff wrote:
guy25 wrote:
I have a pair of B&W 801 series 2 and one speaker's crossover over
load and burned (a round orange coil) is this repair able? any
information will be very appreciates. I'm living in Chicago. Thanks
in advance, guy25

No , it's not repairable. Send the speakers to me.

geoff

Actually, of course it is repairable. But given the value of the speakers
would contact B&W for a local service agent, and a source of the genuine
spare part.

geoff

First of all I'd like to thanks everybody in this forum so friendly and helpful. I removed the L1 coil and inspected, it turn out O.K but the 3 Ceramic resistor next to it was got over heated. It's: R1=0R47-7W , R3=5R6-7W and R4=8R2-7W. Please take a look at the speaker diagram. I'm sorry, can not paste the Diagram here. I have been trying Google for these resistor with out success. Does anybody here know where to buy it please let me know. Thanks again, Guy25

[Mr.T]

"guy25" wrote in message
...
First of all I'd like to thanks everybody in this forum so friendly and
helpful. I removed the L1 coil and inspected, it turn out O.K but the 3
Ceramic resistor next to it was got over heated. It's: R1=0R47-7W ,
R3=5R6-7W and R4=8R2-7W. Please take a look at the speaker diagram. I'm
sorry, can not paste the Diagram here. I have been trying Google for
these resistor with out success. Does anybody here know where to buy it
please let me know. Thanks again, Guy25

You'd certainly have trouble finding generic 7 Watt resistors, but 10 Watt
parts should be readily available, and less likely to fail again.
In case you don't already know, those are 0.47ohm, 5.6 ohm and 8.2 ohm, and
are common values.

MrT.

[Peter Larsen[_3_]]

Mr.T wrote:

You'd certainly have trouble finding generic 7 Watt resistors, but 10
Watt parts should be readily available, and less likely to fail again.

hmm ... yes, but resistors are cheaper than loudspeaker-units, so perhaps it
is worth making an extra effort to find some.

In case you don't already know, those are 0.47ohm, 5.6 ohm and 8.2
ohm, and are common values.

A wise and helpful translation.

MrT

Kind regards

Peter Larsen

[guy25]

You are right Peter.

one of authorize B&W technician here in Chicago gave me a quote that crossover replacement is $900/ea is too much for me.

Just found-out the http://www.uk.farnell.com had these resistor but still wait respond from them to see either they're ship to US or not.

Best regard, Jimmy Pham

[Peter Larsen[_3_]]

guy25 wrote:

You are right Peter.

one of authorize B&W technician here in Chicago gave me a quote that
crossover replacement is $900/ea is too much for me.

You missed my point with a margen of 2 3/4 furlong: my point is that the
resistor powerhandling is chosen so as to make the resistor protect the
loudspeaker unit(s) that get their signal through it.

Just found-out the http://www.uk.farnell.com had these resistor but
still wait respond from them to see either they're ship to US or not.

There's also digikey.com, they're on your side of the pond.

Best regard, Jimmy Pham

Kind regards

Peter Larsen

[David Nebenzahl]

On 5/16/2010 11:17 AM Peter Larsen spake thus:

guy25 wrote:

You are right Peter.

one of authorize B&W technician here in Chicago gave me a quote that
crossover replacement is $900/ea is too much for me.

You missed my point with a margen of 2 3/4 furlong: my point is that the
resistor powerhandling is chosen so as to make the resistor protect the
loudspeaker unit(s) that get their signal through it.

I don't buy that at all. Since when does a resistor, even of a much
lower value than the speaker it's in series with, "protect" a speaker?
It's not a fuse; the resistor is just going to generate heat,
potentially lots of it, and possibly char the surrounding cabinetry
before going "poof".

If one wanted to protect a speaker, a fuse would be the way to do it,
not a lower-wattage resistor.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[David Nebenzahl]

On 5/16/2010 5:40 AM guy25 spake thus:

one of authorize B&W technician here in Chicago gave me a quote that
crossover replacement is $900/ea is too much for me.

$900????!?!?!? WTF?!?!?

Just found-out the http://www.uk.farnell.com had these resistor but
still wait respond from them to see either they're ship to US or not.

Since you're in the US, *forget* Farnell. There's nothing special about
those resistors, just garden-variety power resistors.

The places you ought to be checking are Digikey, Mouser, and Jameco, all
right here in the USofA. You can easily find them (I'd just type their
name directly into the address field, like digikey.com, rather than
doing a Google search). If I have time later I can look for those
resistors, but you should be able to find them easily at any of these
places.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[Mr.T]

"Peter Larsen" wrote in message
k...
You'd certainly have trouble finding generic 7 Watt resistors, but 10
Watt parts should be readily available, and less likely to fail again.

hmm ... yes, but resistors are cheaper than loudspeaker-units, so perhaps
it
is worth making an extra effort to find some.

Why would you make an effort to find a lower rated part unless the 10W ones
wont fit?

MrT.

[Mr.T]

"Peter Larsen" wrote in message
k...
You missed my point with a margen of 2 3/4 furlong: my point is that the
resistor powerhandling is chosen so as to make the resistor protect the
loudspeaker unit(s) that get their signal through it.

Nope, that's what poly-switches, or even fuses are for.

MrT.

[David Nebenzahl]

On 5/16/2010 6:23 PM Mr.T spake thus:

"Peter Larsen" wrote in message
k...

You'd certainly have trouble finding generic 7 Watt resistors, but 10
Watt parts should be readily available, and less likely to fail again.

hmm ... yes, but resistors are cheaper than loudspeaker-units, so
perhaps it is worth making an extra effort to find some.

Why would you make an effort to find a lower rated part unless the 10W ones
wont fit?

He thinks they work like fuses.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[Peter Larsen[_3_]]

David Nebenzahl wrote:

Why would you make an effort to find a lower rated part unless the
10W ones wont fit?

He thinks they work like fuses.

No David, it failed because it actually acted like a fuse. And it is cheaper
that the resistor in series with the loudspeaker unit should fail and
thereby protect the loudspeaker unit than vice versa.


Kind regards

Peter Larsen

[Arny Krueger]

"David Nebenzahl" wrote in message
.com
On 5/16/2010 11:17 AM Peter Larsen spake thus:

You missed my point with a margen of 2 3/4 furlong: my
point is that the resistor powerhandling is chosen so as
to make the resistor protect the loudspeaker unit(s)
that get their signal through it.

I don't buy that at all. Since when does a resistor, even
of a much lower value than the speaker it's in series
with, "protect" a speaker? It's not a fuse; the resistor
is just going to generate heat, potentially lots of it,
and possibly char the surrounding cabinetry before going
"poof".

There are many instances of resistors being used for fuses - for example
resistors in the 0.1 to 10 ohm range are often used this way. However, the
intent is usually rather gross - to prevent a fire or other casualty loss.
Obviously, if a designer wants a well-calibrated fuse, they use a fuse. They
just cost more money than a small resistor.

I'm not familiar with resistors in the 5-10 watt range being used this way.
Usually, internal speaker protection is provided by fuses, light bulbs, or
other non-linear resisive devices.

If one wanted to protect a speaker, a fuse would be the
way to do it, not a lower-wattage resistor.

Agreed.

When a reistor is used as a fuse, it seems unlikely that using a resistor
with only 33% higher wattage would be a deal breaker.

[guy25]

Originally Posted by Peter Larsen[_3_]

David Nebenzahl wrote:

Why would you make an effort to find a lower rated part unless the
10W ones wont fit?

He thinks they work like fuses.

No David, it failed because it actually acted like a fuse. And it is cheaper
that the resistor in series with the loudspeaker unit should fail and
thereby protect the loudspeaker unit than vice versa.


Kind regards

Peter Larsen

Thanks you all. I'm a newbie,actually no nothing about these (very basic). all opinion are very welcome. so please tell me what to do is the best.

I have question for you guy: can I replace the 7W with 10W (the digitkey have resistor available) is it going to work?

If it does work. does it affected the sound stream. All original still in the speaker and have a sweet sound. If I can I really do not want to have the sound different in my system If I still have choice.

please give the advice. I'm still trying to get the replacement for these resistor and will post the result whenever it done. Thanks again and have good day to all. Jimmy Pham

[Peter Larsen[_3_]]

Dick Pierce wrote:

No, it isn't.

Thank you for explaining how I was wrong!

Kind regards

Peter Larsen

[David Nebenzahl]

On 5/17/2010 1:38 AM Peter Larsen spake thus:

David Nebenzahl wrote:

Why would you make an effort to find a lower rated part unless the
10W ones wont fit?

He thinks they work like fuses.

No David, it failed because it actually acted like a fuse. And it is cheaper
that the resistor in series with the loudspeaker unit should fail and
thereby protect the loudspeaker unit than vice versa.

Except that as Dick Pierce has elegantly explained it, the resistor will
*not* actually protect the speaker; in fact, it's far likelier that
*both* the resistor and one or more drivers will be damaged
simultaneously in the event of excessive power applied to the speaker unit.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[Mr.T]

"Peter Larsen" wrote in message
k...
David Nebenzahl wrote:

Why would you make an effort to find a lower rated part unless the
10W ones wont fit?

He thinks they work like fuses.

No David, it failed because it actually acted like a fuse. And it is
cheaper
that the resistor in series with the loudspeaker unit should fail and
thereby protect the loudspeaker unit than vice versa.

Sure, but I'd call that extremely lucky. A cheap polyswitch would do a far
better job at protecting the driver.

MrT.

[guy25]

Thanks Peter,

I talk to digikey on the phone but they do not carried 7W only 10W in stock. Don't you think it works? there also some on ebay but I'm not so sure about quality. Please give me your opinion. Thanks again, Jimmy

[David Nebenzahl]

On 5/17/2010 8:46 PM guy25 spake thus:

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works? there also some on ebay but I'm not so
sure about quality. Please give me your opinion. Thanks again, Jimmy

1. Yes, it will work. Power dissipation has nothing to do with it
"working" or not; it just indicates how much power you can run through
it without damaging it. A 10W resistor resists just like a 7W resistor.

2. Quality, schmality. It's a goddamn *resistor*, for chrissakes.
(Unless you're one of those audiophool suckers who falls for gold-plated
connectors, monster cables and such.) Makes no difference.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[geoff]

David Nebenzahl wrote:
On 5/17/2010 8:46 PM guy25 spake thus:

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works? there also some on ebay but I'm not
so sure about quality. Please give me your opinion. Thanks again,
Jimmy

1. Yes, it will work. Power dissipation has nothing to do with it
"working" or not; it just indicates how much power you can run through
it without damaging it. A 10W resistor resists just like a 7W
resistor.
2. Quality, schmality. It's a goddamn *resistor*, for chrissakes.
(Unless you're one of those audiophool suckers who falls for
gold-plated connectors, monster cables and such.) Makes no difference.

Well actually it is likely to also be an inductor. But probably
insignificantly so.

geoff

[geoff]

Dick Pierce wrote:

Just buy the damned 10 watt resistors and be done
with it.

If it's anything like my KEF Reference speakers (and it should be) , it is
not JUST a 10W resistor.
It is likely to be of a specifically selected value from within the normal
tolerance band, to enable the speaker to comply to it's specifications. KEF
tested and matched up Rs Cs and drivers into bins to make sets that gave
the correct crossover frequencies and attenuations.

I'd be inclined to test the actual value of it's buddy in the adjacent
speaker, and match the resistance to within 1% or so.

We are talking about B&W Nautilus range speaker IIRC, so worth the effort.

geoff

[David Nebenzahl]

On 5/18/2010 1:55 PM geoff spake thus:

David Nebenzahl wrote:

On 5/17/2010 8:46 PM guy25 spake thus:

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works? there also some on ebay but I'm not
so sure about quality. Please give me your opinion. Thanks again,
Jimmy

1. Yes, it will work. Power dissipation has nothing to do with it
"working" or not; it just indicates how much power you can run through
it without damaging it. A 10W resistor resists just like a 7W
resistor.
2. Quality, schmality. It's a goddamn *resistor*, for chrissakes.
(Unless you're one of those audiophool suckers who falls for
gold-plated connectors, monster cables and such.) Makes no difference.

Well actually it is likely to also be an inductor. But probably
insignificantly so.

So it makes no *detectable* difference. Glad we settled that.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[David Nebenzahl]

On 5/18/2010 2:02 PM geoff spake thus:

Dick Pierce wrote:

Just buy the damned 10 watt resistors and be done
with it.

If it's anything like my KEF Reference speakers (and it should be) , it is
not JUST a 10W resistor.
It is likely to be of a specifically selected value from within the normal
tolerance band, to enable the speaker to comply to it's specifications. KEF
tested and matched up Rs Cs and drivers into bins to make sets that gave
the correct crossover frequencies and attenuations.

I'd be inclined to test the actual value of it's buddy in the adjacent
speaker, and match the resistance to within 1% or so.

Do you really think even a 10% deviation from stated value would make
any real difference in the sound, practically speaking?


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[Paul G.]

On Tue, 18 May 2010 16:25:08 -0400, Dick Pierce
wrote:

guy25 wrote:
Thanks Peter,

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works?

Like others have said several times, YES, it will work.

Increasing the wattage for 7 to 10 watts, or from 7 to
15 watts, or to 20 or 50 or 100 watts WILL WORK FINE.

The wattage of the resistor WILL NOT MAKE A DIFFERENCE:

1. If everytging else in the speaker is working fine,
a 10 watts resistor will sound identical to a 7
watt speaker.

2. If, in the process of blowing up the 7 watt resistor,
you blew up something else (which is possible, maybe
even likely), then replacing the 7 watt with a 10 watt
will ALSO make the speaker sound identical, becasue
it's just as broken with a 7 watt resistor as with a
10 watt.

there also some on ebay but I'm not so
sure about quality. Please give me your opinion.

My opinion is that you're WAY overthinking this.

Just buy the damned 10 watt resistors and be done
with it.


There is a remote chance it is a "fusible resistor", I've replaced
these things on older TV sets. They are used extensively in the
electronics industry, especially where temporary large surge currents
are tolerated. If that were the case, you would be required to replace
it with a similiar resistor of the same power rating. 0.47 ohms is a
popular value for a fusible resistor.
They DO have a compartively long time to blow compared to a fuse,
since the resistor must heat up to the point where the fusible element
breaks. In that respect they would be useful in a speaker, since you
could allow large transients, and the resistor would open up before
the voice coil would be damaged.
They were not meant as a consumer replacable item, since the trauma
that caused the resistor to blow usually indicated some circuit
problem or gross abuse.
My guess is that such a low value of resistance would not have much
effect on the audio performance (being swamped out by the voice coil
resistance), and might give more credence to its function as a slow
fuse.
If it is a fusible resistor, it is probably chosen for a specific
thermal time constant. It would not be wise to replace it with an
ordinary resistor, or fusible one of unknown characteristic.

Paul G.

[Mr.T]

"Dick Pierce" wrote in message
...
My opinion is that you're WAY overthinking this.

No he doesn't seem to be *thinking* at all.

Just buy the damned 10 watt resistors and be done
with it.

As I said in my original reply, only reason not to is if it doesn't fit,
which is unlikely in a speaker.
And I also said he should check the drivers, which he still doesn't appear
to have done yet.

Either he is totally out of his depth and should get someone to fix it for
him, or he's just a troll.

MrT.

[Mr.T]

"geoff" wrote in message
...
Dick Pierce wrote:

Just buy the damned 10 watt resistors and be done
with it.

If it's anything like my KEF Reference speakers (and it should be) , it is
not JUST a 10W resistor.
It is likely to be of a specifically selected value from within the normal
tolerance band, to enable the speaker to comply to it's specifications.
KEF
tested and matched up Rs Cs and drivers into bins to make sets that gave
the correct crossover frequencies and attenuations.

I'd be inclined to test the actual value of it's buddy in the adjacent
speaker, and match the resistance to within 1% or so.


Which contradicts your premise since the drivers are different and the
resistors would have to be matched to THAT driver IF you think it's THAT
critical.
The only way would be to properly test it, which is obviously beyond the OP.

MrT.

[David Nebenzahl]

On 5/18/2010 9:26 PM Mr.T spake thus:

"Dick Pierce" wrote in message
...

Just buy the damned 10 watt resistors and be done
with it.

As I said in my original reply, only reason not to is if it doesn't fit,
which is unlikely in a speaker.
And I also said he should check the drivers, which he still doesn't appear
to have done yet.

Either he is totally out of his depth and should get someone to fix it for
him, or he's just a troll.

As usual, you seem to want to jump to conclusions here. While the OP is
obviously not an audio expert, I'm sure he's quite capable of replacing
a lousy resistor in a speaker crossover. Doesn't take a rocket surgeon
to do that.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[Mr.T]

"David Nebenzahl" wrote in message
.com...
Either he is totally out of his depth and should get someone to fix it
for
him, or he's just a troll.

As usual, you seem to want to jump to conclusions here. While the OP is
obviously not an audio expert, I'm sure he's quite capable of replacing
a lousy resistor in a speaker crossover. Doesn't take a rocket surgeon
to do that.

Exactly, which is why I say someone who keeps asking the sort of questions
he has, when told ages ago to simply buy readily available 10W items, is
surely out of his depth at the very least. And we still don't know if the
driver is even OK!

Perhaps you are the one jumping to conclusions believing that everyone can
in fact perform simple tasks without a lot of handholding. The OP has shown
he at least requires the latter.

MrT.

[David Nebenzahl]

On 5/19/2010 12:40 AM Mr.T spake thus:

"David Nebenzahl" wrote in message
.com...

Either he is totally out of his depth and should get someone to
fix it for him, or he's just a troll.

As usual, you seem to want to jump to conclusions here. While the OP is
obviously not an audio expert, I'm sure he's quite capable of replacing
a lousy resistor in a speaker crossover. Doesn't take a rocket surgeon
to do that.

Exactly, which is why I say someone who keeps asking the sort of questions
he has, when told ages ago to simply buy readily available 10W items, is
surely out of his depth at the very least. And we still don't know if the
driver is even OK!

Perhaps you are the one jumping to conclusions believing that everyone can
in fact perform simple tasks without a lot of handholding. The OP has shown
he at least requires the latter.

The question isn't really whether the O.P. can handle the repair, but
whether they're ready to quit overthinking the problem and just order
the damned resistor. That seems to be their problem.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[GregS[_3_]]

In article , David Nebenzahl wrote:
On 5/18/2010 1:55 PM geoff spake thus:

David Nebenzahl wrote:

On 5/17/2010 8:46 PM guy25 spake thus:

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works? there also some on ebay but I'm not
so sure about quality. Please give me your opinion. Thanks again,
Jimmy

1. Yes, it will work. Power dissipation has nothing to do with it
"working" or not; it just indicates how much power you can run through
it without damaging it. A 10W resistor resists just like a 7W
resistor.
2. Quality, schmality. It's a goddamn *resistor*, for chrissakes.
(Unless you're one of those audiophool suckers who falls for
gold-plated connectors, monster cables and such.) Makes no difference.

Well actually it is likely to also be an inductor. But probably
insignificantly so.

So it makes no *detectable* difference. Glad we settled that.


I'm sure it can be measured, thus detected.

greg

[GregS[_3_]]

In article , David Nebenzahl wrote:
On 5/16/2010 5:40 AM guy25 spake thus:

one of authorize B&W technician here in Chicago gave me a quote that
crossover replacement is $900/ea is too much for me.

$900????!?!?!? WTF?!?!?

Just found-out the http://www.uk.farnell.com had these resistor but
still wait respond from them to see either they're ship to US or not.

Since you're in the US, *forget* Farnell. There's nothing special about
those resistors, just garden-variety power resistors.

The places you ought to be checking are Digikey, Mouser, and Jameco, all
right here in the USofA. You can easily find them (I'd just type their
name directly into the address field, like digikey.com, rather than
doing a Google search). If I have time later I can look for those
resistors, but you should be able to find them easily at any of these
places.



You forgot, Allied, Newark(who is owned by Farnell, and parts can be ordered from any, Farnell, MCM, or Newark),
For unusual power resistors, I would check the surplus houses, or buy it from the maufacturer.

I tried Farnell parametric search and its slow, but it does look like some values there.
If you order throgh Newark it will still have a time delay.

greg

[GregS[_3_]]

In article , "Mr.T" MrT@home wrote:

"Peter Larsen" wrote in message
. dk...
David Nebenzahl wrote:

Why would you make an effort to find a lower rated part unless the
10W ones wont fit?

He thinks they work like fuses.

No David, it failed because it actually acted like a fuse. And it is
cheaper
that the resistor in series with the loudspeaker unit should fail and
thereby protect the loudspeaker unit than vice versa.

Sure, but I'd call that extremely lucky. A cheap polyswitch would do a far
better job at protecting the driver.

MrT.

We have no idea of what the speaker did without looking and testing all components.
I don't think the OP will do this, and he will likely still have problems.

When its all said and done, I myself would listen to
the pair with pink noise.

I worked a little with poly switches. You can get both negative and positive devices.
It critical to know the the trip current of the device and also the exact
Z of the drivers. They are tricky, are not foolproof, and can also interefere the
performance.

I have seen sand power resistors get awfull looking yet still work.
I would rather use fire proof resistors at times than carbon or film resistors,
which thae later seem to be in abundance in my parts bin.

greg

[David Nebenzahl]

On 5/19/2010 10:56 AM GregS spake thus:

In article , David
Nebenzahl wrote:

On 5/18/2010 1:55 PM geoff spake thus:

David Nebenzahl wrote:

On 5/17/2010 8:46 PM guy25 spake thus:

I talk to digikey on the phone but they do not carried 7W only 10W in
stock. Don't you think it works? there also some on ebay but I'm not
so sure about quality. Please give me your opinion. Thanks again,

1. Yes, it will work. Power dissipation has nothing to do with it
"working" or not; it just indicates how much power you can run through
it without damaging it. A 10W resistor resists just like a 7W
resistor.
2. Quality, schmality. It's a goddamn *resistor*, for chrissakes.
(Unless you're one of those audiophool suckers who falls for
gold-plated connectors, monster cables and such.) Makes no difference.

Well actually it is likely to also be an inductor. But probably
insignificantly so.

So it makes no *detectable* difference. Glad we settled that.

I'm sure it can be measured, thus detected.

So this is what, a "golden ears" observation?

Come on, get real. I'm starting to think that the problem in this thread
isn't that the O.P. is overthinking things, as Dick Pierce has surmised
(or that he's just an idiot, per Meat Plow's usual conclusion). Well, if
he is full of doubt and uncertainty, it's because people like you keep
posting things that make him believe that he can't just replace the
damned resistor with an ordinary power resistor and be done with it. So
thanks for muddying the waters here.


--
The fashion in killing has an insouciant, flirty style this spring,
with the flaunting of well-defined muscle, wrapped in flags.

- Comment from an article on Antiwar.com (http://antiwar.com)

[geoff]

David Nebenzahl wrote:
On 5/18/2010 2:02 PM geoff spake thus:

Dick Pierce wrote:

Just buy the damned 10 watt resistors and be done
with it.

If it's anything like my KEF Reference speakers (and it should be) ,
it is not JUST a 10W resistor.
It is likely to be of a specifically selected value from within the
normal tolerance band, to enable the speaker to comply to it's
specifications. KEF tested and matched up Rs Cs and drivers into
bins to make sets that gave the correct crossover frequencies and
attenuations. I'd be inclined to test the actual value of it's buddy in
the
adjacent speaker, and match the resistance to within 1% or so.

Do you really think even a 10% deviation from stated value would make
any real difference in the sound, practically speaking?

Yep, if your chain, environment, and listening skills are up to it.

We are talking about speaker that cost over $10K here, so I think it would
be sacrilege to throw in something that devalues them in any way.

geoff

[geoff]

Dick Pierce wrote:

We are talking about B&W Nautilus range speaker IIRC.

No, we are not. He stated they are B&W 801 series 2, just
like the thread title says.

OK, similar quality, but older. Why not put the right part in ? And not
talking about wattage or inductance.

geoff

[geoff]

Mr.T wrote:
adjacent speaker, and match the resistance to within 1% or so.


Which contradicts your premise since the drivers are different and the
resistors would have to be matched to THAT driver IF you think it's
THAT critical.
The only way would be to properly test it, which is obviously beyond
the OP.

The original pair of speakers would be matched to around 0.5dB. Why not do
it right, or get somebody competent to do it ?

geoff