NVA AMPLIFICATION - DESIGNED WITH THE QUAD ESL-57
In the late 1970s, NVA founder Richard Dunn was designing and building PA amplifiers under the name Tresham. After he sold those designs to Tannoy, he started looking at amplifier circuits for domestic use. The speaker that he used to develop the NVA circuit that we know and love today, was the Quad ESL-57 electrostatic design.
In 2014, Richard said "for me the ESL-57 was the best development tool available to me at the time as moving coil speakers were just not open or clean enough for what I was trying to achieve with the circuit. And I needed to hear very clearly into the music."
It's not surprising, then, that NVA amplifiers are an excellent match with the vintage Quad design. The ESL-57s don't need lots of power; our 35 watt S80 (with P50 passive pre-amplifier) is all you will ever need, though you can get even better sound quality with the larger NVA power amplifiers.
Several members of our Hi-fi Subjectivist forum own / have owned the ESL-57s. HFS member, Terry Booth, says...
"I first heard them in the Science Museum in London, they were suspended high up pointing down in an exhibition of hifi (this is in the 1960s). I fell in love with them and had to have a pair. I bought mine during the three day week in the early 1970s, when supply was being limited - had to search high and low for a pair.
Need to be in a lot of space to work best - not pushed up against a wall. The last time I heard a pair - in a fairly small room, they were about three feet out from the wall. The person I know who owned them then bought the newer ones - 28s and 29s I think they were then."
We asked past and present ESL-57 owners for their tips on buying / maintaining and optimising the sound quality of this cult speaker.:
- Space behind them. The Quads, like any other electrostatic / panel speaker we can think of, need to be pulled away from the rear wall. 3 feet should be OK, 4 to 5 feet would be ideal. That doesn't necessarily rule out nearfield listening in a small room, if you can get the geometry right.
- Less fussy about side walls. The ESL-57s can be used pretty close to side walls without adverse effect. One owner reported that their 57s were happy 'right up against them' but a minimum of 6 inches seems sensible, to us.
- Maintenance - regular servicing (around every 10 years) will keep your Quads sounding as they should. Sparking or hissing are obvious signs that work is required. The sound gradually becoming duller, and / or bass output falling, are other, less dramatic indicators that attention is required.
- Buy a set with everything already done - is a great option as you can often pick up a fully refurbished pair for less than the total price of the work. Be sure that the work has been done by a genuine expert, and ask to see receipts.
- Buy an original set with nothing done. Another great option (at the right price) - you assume that everything needs to be done, and you get to choose how original you keep your set, and who does the work. In the UK, we recommend Andrew Jones at aquadthing.com
- Stands for the Quad ESL57 are essential. The original mono design was made to incline backwards and bounce the sound off a ceiling; this was when most ceilings were very high, not today's low ceilings in modern rooms. To redress this you need a stand that raises the Quads about 12 to 18 inches off the floor and tilts the speaker forward until it is straight facing the listener. There are ready made Rupert Stands available but if you are either handy with woodwork or have a local joiner you can go to then I think you could easily make a sensible set without too much expense.
You can find more quad ESL-57 opinion and advice on this HFS thread