AR-6 RE-cap ....increase in volume????

[Hodge]

Hi all, looking for some guidance / reassurance please.

I recently re-capped a pair of AR-6 speakers, using like for like new capacitors and resistors (original on the woofer).

Since re-capping , overall sound quality is fine, and I’m pleased with the result, but noted that even when I have turned the amp volume down to 0, I can still hear sound clearly through the speakers. The source is CD, so it’s not some sort of LP cartridge resonance - not sure if that’s correct term, but either way, it’s not that. And hasn’t occurred before and doesn’t occur with other speakers.

So, any clues would be great please. Especially if I’ve introduced any risk the the speakers or amp.

Recap approach was same as described in the forum here by a number of other members, and is pretty straightforward, so I’m a bit concerned if I’ve done something wrong or used incorrect components.

thanks in advance for any guidance.

cheers, Paul 

[RoyC]

Paul,

Have you checked your cabinets' input connections, especially as it pertains to the terminals (2 and T) connected with the jumper wire? I seem to recall this being an issue for someone who inadvertently jumper-ed 1 and 2 together, then connected the amp leads to T and 1. The only other possibility is something amiss with your crossover and/or level control wiring...which means some photos will be required.

Roy

[Hodge]

Thanks RoyC, I’ll do some photos soon. My pair only has 2 terminals, 1 and 2 , with no 3rd point or jumper wire. It does have a 3 position toggle switch , currently set at ‘Normal’. 
I am going to swap out the amp just to rule that out, but it seems too coincidental to rule out something I’ve done with the recap. Could be that my connections with the new caps are not firm enough - I have used a mechanical connection initially before I solder everything , so maybe something is not connecting well. 
The caps themselves are all new and tested well before being installed, so don’t think the components are likely culprits. 
I did install new ceramic resistors on the woofers as the originals had obviously overheated at some point , based on scorching to the cabinet fill material . 
I’ll send some photos and perhaps you can spot something.

Thanks again, Paul 

[lance G]

I must bow to RoyC's superior knowledge but my personal thoughts are: For the speakers to make any sound a signal of some level has to be reaching them. If they were disconnected altogether there obviously would be no sound.

They are passive devices, I would be be looking elsewhere. Perhaps the capacitor change has made the speakers more sensitive and you can now hear a signal that was always there ?

I guess some form of RF or induction could be responsible ? How far away are your electronics from the speakers ?

 

[AR surround]

10 hours ago, Hodge said:

Since re-capping , overall sound quality is fine, and I’m pleased with the result, but noted that even when I have turned the amp volume down to 0, I can still hear sound clearly through the speakers. The source is CD, so it’s not some sort of LP cartridge resonance - not sure if that’s correct term, but either way, it’s not that. And hasn’t occurred before and doesn’t occur with other speakers.

So just to clarify, the 'sound' you are hearing with the volume at 0 is music that is on the CD, not spurious noise.  Correct?

[Aadams]

28 minutes ago, AR surround said:

So just to clarify, the 'sound' you are hearing with the volume at 0 is music that is on the CD, not spurious noise.  Correct

Good question it sounds like crosstalk in the amp circuits.

[RoyC]

12 hours ago, Hodge said:

My pair only has 2 terminals, 1 and 2 , with no 3rd point or jumper wire. It does have a 3 position toggle switch , currently set at ‘Normal’. 

Ha, well there goes that theory out the window. Only the early 6's have 3 terminals.

The only reason I didn't mention the amp as a possibility was the statement that "...and hasn’t occurred before and doesn’t occur with other speakers". The AR-6 is not an unusual design and shouldn't behave differently than other speakers, new capacitors or not.

Roy

[Hodge]

8 hours ago, AR surround said:

So just to clarify, the 'sound' you are hearing with the volume at 0 is music that is on the CD, not spurious noise.  Correct?

Hi all, thanks for the responses so far.

To clarify, the sound is not a random source, it’s the CD being played, but is still distinctly audible even when the amp is turned down to zero volume.

i identified it as I’m in the habit of turning my amps back to zero before powering down. Only started after recapping.

so not being picked up from another source.

Thoughts?

[genek]

Zero on a volume control is not a disconnect. There is still voltage going through the amplifier to the speakers. And the CD players I've had over the years have always had the highest outputs of anything I plugged into my amplifiers. A very sensitive speaker could receive enough signal to produce sound.

Although the idea of any classic era AR speaker being called "very sensitive" kind of boggles my mind.

[Aadams]

32 minutes ago, Hodge said:

Thoughts?

It might be simpler to connect another pair of speakers and see if the problem is duplicated.  Is your amp a vintage unit?  Pre 1990s?

[Hodge]

2 hours ago, Aadams said:

It might be simpler to connect another pair of speakers and see if the problem is duplicated.  Is your amp a vintage unit?  Pre 1990s?

Thanks Genek and Aadams, my next step is to see if I can replicate the issue with another amp and speaker combo, ideally to rule out the source as the issue. 
I’m no tech, so I’m showing my ignorance here, but I wonder if the new capacitors and resistors could influence the sensitivity of the speakers, therefore creating the volume issue? The capacitors and resistors match originals ( at least in basic specs, higher voltage rating on capacitors than originals I think?), so whilst I expected some minor sonic difference, I didn’t anticipate the volume issue. 
anyhoo, I’ll swap out the speakers, see what happens, then Swap out amp and CD and report back.

cheers, Paul

[Hodge]

1 hour ago, Hodge said:

Thanks Genek and Aadams, my next step is to see if I can replicate the issue with another amp and speaker combo, ideally to rule out the source as the issue. 
I’m no tech, so I’m showing my ignorance here, but I wonder if the new capacitors and resistors could influence the sensitivity of the speakers, therefore creating the volume issue? The capacitors and resistors match originals ( at least in basic specs, higher voltage rating on capacitors than originals I think?), so whilst I expected some minor sonic difference, I didn’t anticipate the volume issue. 
anyhoo, I’ll swap out the speakers, see what happens, then Swap out amp and CD and report back.

cheers, Paul

Quick update - swapped out speakers, they’re not the problem. So down to amp and /or CD player. I’ll swap out CD next and see what happens. 

[Hodge]

Latest update - So after swapping out speakers and CD, I’d say it’s the amp.

It’s  possible it’s been there for a while and I only noted it because ARS were a bit more sensitive / responsive?

anyhoo, next question is whether it’s indicative of an issue with the amp that may cause problems, or something I can safely ignore?

amp is an older Cambridge Azur 650A, never been serviced but hasn’t shown issues previously and sounds great otherwise. 

thanks, Paul. 

[genek]

My guess is there's probably nothing wrong with the amp at all. As previously mentioned, volume control all the way down does not mean there's no signal, just that the signal is hugely attenuated.

If CDs are the only source that causes sound to come out of the speaker, then it's the CD player. Its output is probably grossly higher than the standard 0.775 VRMS @ 0 VU. If the CD player doesn't have an output level control, try to find a service manual for it online and see if it has internal trimmer pots.