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da2222
02-12-2011, 11:04
I was wondering if the QUAD 57s be a possible match for my NAF 845SE 25W SET amp. I do remember reading somewhere that SETs are not recommended with 57s but perhaps that only applied to lower powered types. Any SET experiences with the 57s?

Thanks

Ali Tait
02-12-2011, 17:46
Yes, I used to use my WAD 300b PSE's with a pair of 57's. Sounded great. I'd say give it a go, maybe try a pair on your amps before you buy though.

I've also used a Mr Liang 845 with a pair of ER Audio ESL III's which also sounded good, though an Audioromy 813 was better, probably because of the extra power, as despite the claims of Liang, the amp was only actually about 8w/ch, and the Audioromy about 30-35. Both amps are SE.

da2222
03-12-2011, 10:01
Thanks Ali...good to know. I use my 845 set with QUAD 63s at the moment and have yet to encounter problems, so hopefully it'll be a good match with the 57s

The quote I was looking for is: "Their (QUAD 57) impedance drops as the frequency increases. This makes the Quad ESL a bad choice for single ended tube (SET) amplifiers".

Ali Tait
03-12-2011, 10:18
Yes, all statics have a drop in impedance up in the treble somewhere, the 57's being particularly bad in this respect I believe. I didn't find it a problem in practice with valve amps, more likely to upset some sand amps possibly.

I have a pair of ER Audio Acorns, not in use at the moment as I need to repair one of the panels, for which a friend is building a pair of direct coupled monoblocks using GM70's. This is the best solution for driving statics with valves IMHO, as it removes two transformers from the signal path. Having had a breadboarded prototype for a while, I found in some respects this was the best sound I've ever heard from any system. The caveats are that it's expensive to do properly, and you need to use high voltage cable as speaker wire, as you will have several thousand volts going from amp to speaker. The sound quality is unmatched though IME.