Quad ESL 57+A&R Cambridge A60 amp?

[spendorman]

Does anyone know if this is safe? Will the A60 be able to handle the very low impedance at high frequency that the Quad ESL 57 presents?

Thanks

[Barry]

Does anyone know if this is safe? Will the A60 be able to handle the very low impedance at high frequency that the Quad ESL 57 presents?

Thanks

Somebody called 'Radfordman' asked this very question on PFM on 19.08.09 at 14:05. Was it you?

You might therefore be interested in post #16, made at 13:04 on 20.08.09 by 'Robert' of Audiosmile, who has run the very test for you without problems.

I would only add to make sure the maximum peak voltage the A60 can present at the speaker terminals is no greater than 28V (20V rms), otherwise the Quad 57s could be damaged by arcing.

[DSJR]

Robert's (Rob Holt) A60 has also benefitted from a full re-build too, remember.. I wouldn't like to risk it on a twenty-five year old amp that hasn't been serviced.

I'd also see if the limiters are still available for the 57's if they're not fitted already. This opens them up to a wider range of power outputs as long as the amp is stable with the load - a friend uses a 606 with hers with no worries (they're never played very loudly yet the sound was still more "comfortable" than with the 405-2 she used previously.

[spendorman]

Somebody called 'Radfordman' asked this very question on PFM on 19.08.09 at 14:05. Was it you?

You might therefore be interested in post #16, made at 13:04 on 20.08.09 by 'Robert' of Audiosmile, who has run the very test for you without problems.

I would only add to make sure the maximum peak voltage the A60 can present at the speaker terminals is no greater than 28V (20V rms), otherwise the Quad 57s could be damaged by arcing.

Thanks Barry, yes it was me! I posted in both forums as I thought it might be an obscure question, but there has been more interest than I expected. This query was for a friend, but I have three A60's and Quad ESL57's as well. I have not tried the combination, in fact I have not run my 57's for something like 20 years. Criminal I know.

It must be more than 25 years ago I fitted the Quad addition filter (I think it was that) to my 57's to enable them to be used with a Quad 303 rather than the Quad II that I was using. Am I correct, this is just a filter not a clamp?

Good point about the 20 V RMS.

[spendorman]

Robert's (Rob Holt) A60 has also benefitted from a full re-build too, remember.. I wouldn't like to risk it on a twenty-five year old amp that hasn't been serviced.

I'd also see if the limiters are still available for the 57's if they're not fitted already. This opens them up to a wider range of power outputs as long as the amp is stable with the load - a friend uses a 606 with hers with no worries (they're never played very loudly yet the sound was still more "comfortable" than with the 405-2 she used previously.

Thanks DSJR, The original question relates to a friends A60 (unserviced) and a pair of 57s that he yet to purchase.

I am a bit confused about limiters, my own 57's (which I have not used for about 20 years) I put the Quad mod in to enable them to be used with a 303, rather than the Quad II that I was using previously. This was probably about 25 years ago, I suppose these are filters not limiters?

My own A60 (three) have been serviced and the most recently produced one is late enough to have included the Arcam upgrade components.

[hifi_dave]

I did try that combination many years ago when the A60 was a current model and I wouldn't recommend it. The A60 struggled, sounded like crap and after a few minutes blew it's fuses.

The 57's deserve better or, at least, something more suitable like a Quad 303 if you are on a budget.

[DSJR]

the "filters" or whatever you wish to call them, don't necessarily improve the capacitive loading, but do enable far beefier amps to be used with 57's. I suspect you have them already fitted.

If your mate hasn't bought 57's yet, tell him to save his money and/or buy some Spendor SP1's. They don't "beam," they won't have gone off like most 57's have by now and they have comparable sound quality, much higher power handling, less coloured treble (none of the "plastic diaphragm treble) and they're still affordable to buy........

[spendorman]

the "filters" or whatever you wish to call them, don't necessarily improve the capacitive loading, but do enable far beefier amps to be used with 57's. I suspect you have them already fitted.

If your mate hasn't bought 57's yet, tell him to save his money and/or buy some Spendor SP1's. They don't "beam," they won't have gone off like most 57's have by now and they have comparable sound quality, much higher power handling, less coloured treble (none of the "plastic diaphragm treble) and they're still affordable to buy........

That seems very reasonable advice, I had told him that the 57's have to be in tip top condition (and most aren't) to sound really good. Coincidentally he has BC1's. I did suggest the SP1, perhaps I will try again.

Thanks.

[DSJR]

There's a bit you can do to BC1's to sort the bass out - better stands, port-tubes from Maplin that just push in and easily removable and a small 12" cushion inner in the top of each cabinet - works for me on the BC2's...

By the way, Peter Walker rated the BC1 OVER the esl 57 back in the day...

If the BC1's are early ones with what's left of the original white surrounds (which shrink back into a flat sheet from the half-roll they were made as), but are OK otherwise, then Spendor's Terry Miles can re-build them (he can do BC1's but not BC2's sadly). Although he doesn't make a big thing of it, the crossover caps and resistors could be replaced, although the caps Spendor used have a far longer life than the electrolytics used by others and apparently they were selected first anyway. The Hf1300 tweeters can still be re-built if necessary and the Coles tweeters are still available in the high impedance version specified by Spendor.

Seriously, I'd get a better amp (the A60 is great, but still a "budget" model) and do up the BC1's. The SP1 was more like a souped-up BC2 with a slightly sweeter top.

Finally, I HAVE compared the BC1's I used to own with a then new pair of 57's. The overal quality of sound is directly comparable, with the 57's being even fussier 'cos of the hyper-beaming tweeter and the bass being less extended, despite better quality down there compared to my '76 era BC1's (they were substantially re-tuned in the ports in 1980 or thereabouts)

[spendorman]

There's a bit you can do to BC1's to sort the bass out - better stands, port-tubes from Maplin that just push in and easily removable and a small 12" cushion inner in the top of each cabinet - works for me on the BC2's...

By the way, Peter Walker rated the BC1 OVER the esl 57 back in the day...

If the BC1's are early ones with what's left of the original white surrounds (which shrink back into a flat sheet from the half-roll they were made as), but are OK otherwise, then Spendor's Terry Miles can re-build them (he can do BC1's but not BC2's sadly). Although he doesn't make a big thing of it, the crossover caps and resistors could be replaced, although the caps Spendor used have a far longer life than the electrolytics used by others and apparently they were selected first anyway. The Hf1300 tweeters can still be re-built if necessary and the Coles tweeters are still available in the high impedance version specified by Spendor.

Seriously, I'd get a better amp (the A60 is great, but still a "budget" model) and do up the BC1's. The SP1 was more like a souped-up BC2 with a slightly sweeter top.

Finally, I HAVE compared the BC1's I used to own with a then new pair of 57's. The overal quality of sound is directly comparable, with the 57's being even fussier 'cos of the hyper-beaming tweeter and the bass being less extended, despite better quality down there compared to my '76 era BC1's (they were substantially re-tuned in the ports in 1980 or thereabouts)

Thanks for a comprehensive answer, his BC1s have the black surrounds and the port mod. He was having problems of boomy bass, but the port mod helped and the the A60 helped further (over the Quad integrated, forget the model).

As regards the comparison of BC1 and ESL63 (I have both) and comparing them (just over 20 years ago when my hearing was better!) I found the the midrange of the 57's far superior (less coloured and more detailed). However, it's all about personal preference. Certainly, my hearing has changed, not just the loss of top end, but I am much more critical of midrange coloration these days.

I really must get the ESL57's out again. Not to mention the ESL63s. They have not been used since the cat got at them. It must have been delighted at finding not just one giant scratching post, but two. New socks were bought from Quad. That was all that was required.

Last night I tried my latish A60 with some Tangent RS2's, surprised how well they worked together, very nice really.

Oh, and your recommendation of extra damping in the BC1, that was tried and helped as well.

[DSJR]

The 63's were different to the 57's and needed to be off the ground and tilted back slightly. 57's weren't especially tuneful in the bass, but the mid could be excellent.

BC1's do have a plump bass, but this got much better with later ones. BC2's are rather different, but the upper-mid isn't "quite" as smooth as the BC1. The SP1 to me has the strengths of both its predecessors IMO..

Another speaker that compared very well directly with 57's was the ATC 20's, but the compromise with these is that they need a zillion watts to row them along, despite their being a doddle of a load otherwise.

You know, despite a certain synthetic "character," the Yamaha NS1000 holds its value well and the A60 may just cope fine with it...................

[RobHolt]

Just spotted this thread.

Might be worth clarifying the position wrt filters and limiters on the 57.

There were two modifications.
The first was a crossover mod performed around the time that the 303 was introduced which limited LF reaching the treble panels. Bass panels are near impossible to arc and the treble panel is commonly arched by too much voltage at LF.

The second mod was the voltage clamp that would trigger if excessive voltage (at any frequency) is applied to the treble panel.