Refurbished, serviced, rebuilt ... what's in a word? My "puzzler ... [is] sore" (Dr. Seuss).

[George J]

Dear Disco,

You are very much in the territory of - for example - an unmolested Baroque organ from Bach’s time, compared to a much modernised instrument from the time.

No doubt that Bach’s organ music is best served on an organ in good sympathetically rebuilt [unmodofied] condition from his own time than a much modified sample, but one can never know how closely the a truly old specified organ resembles what Bach would have thought normal. That is never going to happen. It is not possible.

But I had a great surprise to find some recordings made sixrty years apart of of two Schnitke organs [in Cappel and in Holland] recorded by DG and by Quad and you know that the qualities of these two ancient and almost no more than properly serviced for centuries old instruments showed exact similarities of pipe voicing, even in such diverse recordings.

The reality is that good sympathetically serviced classic Leak and Quad sound finer in classical music than anything made since including the arTless modifications to make these old pieces of hifi sound more modern.

The reality remains that hifi has been on a musically downward trend since at least the late 1960s. Before that music was more important than effect, and noawdays effect takes precedence every time. Stereo is an example of this. Stereo is an abomination of the worst kind. If it mattered where the musicians exactly were when giving the performance, by now we would have a standardised layout for orchestras and ensembles, but we don’t. It is a non-issues. And it double the cost of power amplifiers and speakers for a given level of claimed quality.

For Tony L. Forget matching your beautiful TL 12 with another. Simply match it to a single ESL and be happy!

ATB from George

 

[koi]

Has anybody heard a Quad, Leak with all original components that are exactly within specification (under all temperature conditions) to be so sure as to what they originally sound like.
Where can one buy original carbon resistors that are still within spec, non leaking TCC paper in oil caps etc.?

You have a point while everyone would like old amplifiers to sound like they did when they were made it’s near on impossible

Are electricity supply has even altered since them good old days

While I agree some alter them a bit to far

Newer components installed like for like cannot do any harm

My view anyway.

 

[Tony L]

There are certainly folk in Japan running largely unrestored Leaks, I assume they have reformed the caps gently on a variac or whatever. Regardless at this point in time we can still find equivalents, e.g. if a component was PIO or carbon in original spec it can still be replaced pretty much like for like. It makes far more sense to do this than alter the design IMO (and I am sure I am in the majority of those who own and use this type of kit). If one has an original 1957 Fender Strat one would be an idiot to replace the pickups and wiring or paint it bright orange or whatever. If you want to do that don’t start from a valuable classic. Sympathetic repair to restore functionality should be the limit of restoration IMO.

PS George, I have a single Wharfedale SFB/3 should I want to go classic mono. It needs the drivers refoaming but other than that is complete and tidy, I assume it is from the same original system as the TL12, a Varislope pre and a champagne colour Mk I Troughline tuner I also brought back from the same place!

 

[Julf]

When I restore a classic car, should I stick to NOS spark plugs, oil filters and tyres? The problem is that 50-year-old tyres are pretty dry, cracked and hard by now, but, you know, the original designer designed the handling for old cross-ply tires, not modern radials with grippier rubber...

 

[Tony L]

When I restore a classic car, should I stick to NOS spark plugs, oil filters and tyres? The problem is that 50-year-old tyres are pretty dry, cracked and hard by now, but, you know, the original designer designed the handling for old cross-ply tires, not modern radials with grippier rubber...

You have to use what is available, but if you put big fat slicks and low profile alloys on a vintage MG or whatever you are a bit of a cock in my book! Luckily in the world of audio we are fine as military quality and highly reliable PIO caps are widely available and still cheap (see my link upthread) and one can buy a whole range of brand new resistors of different construction types. Properly restoring a vintage tube amp without botches or mods is perfectly possible even easy these days now their value is more appreciated. Restoring that SFB will be a lot more challenging as the parts do not exist so will have to be custom made. By saying that I did that with my JR149 grilles so getting things made is possible, assuming one can find the spec...

 

[George J]

"PS George, I have a single Wharfedale SFB/3 should I want to go classic mono. It needs the drivers refoaming but other than that is complete and tidy, I assume it is from the same original system as the TL12, a Varislope pre and a champagne colour Mk I Troughline tuner I also brought back from the same place!”

Fix the speaaker and have a unique opportunity to sample something like what was intended. If you don’t like it much then give the speaker to a museum! I have single 1957 made [unmodified though fairly recently Huntingdon restored] ESL and currently a problem with my Quad valve amp. I intend to put a TL 12.1 in un-modified condition to drive this wonderful transducer but there are many ways forward. I imagine that Classique in Leicester will need to check the old Leak out for safety.

ATB from George

 

[disco]

There are certainly folk in Japan running largely unrestored Leaks, I assume they have reformed the caps gently on a variac or whatever. Regardless at this point in time we can still find equivalents, e.g. if a component was PIO or carbon in original spec it can still be replaced pretty much like for like. It makes far more sense to do this than alter the design IMO (and I am sure I am in the majority of those who own and use this type of kit). If one has an original 1957 Fender Strat one would be an idiot to replace the pickups and wiring or paint it bright orange or whatever. If you want to do that don’t start from a valuable classic. Sympathetic repair to restore functionality should be the limit of restoration IMO.

PS George, I have a single Wharfedale SFB/3 should I want to go classic mono. It needs the drivers refoaming but other than that is complete and tidy, I assume it is from the same original system as the TL12, a Varislope pre and a champagne colour Mk I Troughline tuner I also brought back from the same place!

If this is true then the Japanese are running Leaks that are out of spec. and do not sound like the original. They also buy discarded and leaking TCC caps off Ebay after which they bore them out and fit a modern propylene cap inside so that the amp looks original. I'll never understand the far eastern mentality and certainly would not refer to them to reinforce my argument.
Fitting modern resistors and capacitors is not 'altering the design'; in fact it is an attempt to comply with the original design requirement and I believe is exactly what Arthur Radford, Harold Leak and Peter Walker would have done in the same situation. Neither do I believe for one moment that they would then proceed by modifying the original design because the resultant 'voicing' has changed.

Can anybody advise on a source of appropriate original type carbon resistors as all of my new old stock has gone out of spec?

 

[Tony L]

Have a look at Hi-Fi Collective for several choices of carbon resistors, other similar retailers will have other alternates. You may well be right about the Japanese drilling out old TCCs, I'm just going on pictures of their restorations, I can't read Japanese. I disagree with you fundamentally when it comes to modern film caps etc being identical, they just aren't. Any guitarist or high-end tube amp maker will tell you that. That is not to say modern film caps are not excellent, I'm not saying that at all and the very last thing I'd ever do is swap high-end teflon or film caps in a Conrad Johnson or whatever for PIO! I'm buying a designer's work, if it is old and needs restoring I will do it as close as possible to original spec as I want that specific designer's work, not what some random bloke on the internet recommends! If I could buy factory fresh new TCCs or whatever that is what would be in my Leak. As it is the Russian K40Y-9s seem to be the closest available truly reliable replacement, so that is what I will use.

PS I do own what I am pretty sure is a NOS Stereo 20 and there is no way I'd power it on as-is! I don't need it so I'm just keeping it in its box as an investment/backup in case something irreplaceable fails on my rebuilt one.

 

[disco]

I never made the statement that modern film caps etc are identical. Neither would I refer to guitarists to reinforce any argument regarding hi-fidelity. Most seek and thrive on the dirtiest, distorted and different sound they can find.

 

[Paul R]

Peter Walker, Harold Leak, Arthur Radford and the rest, given today's technology and yesterday's environment wouldn't make yesterday's amps. Of course they'd be in some other business if born 50 years later.

So, IMO, classic amps should be minimally maintained to keep them working as intended, or simply stored away.

If you want a better amp then buy one intended to be better.

Regardless, I think 15W classic tube amps into ELS57 have a particular sound, and it's a waste of the speaker and all about the amp struggling*. Find a modern 50W amp and get the best out of them. A Quad 306 might be an idiomatic solution.

Paul

*Some people like this clipping and limited extension, pipe and slippers etc. But the speakers remain as good as it gets within their envelope and with a sympathetic situation so you can hear them, but you need a good amp.

 

[Tony L]

I have a feeling you play music *a lot* louder than me! A 15 Watt Quad II will happily drive a ESL as loud as I'd ever want.

 

[disco]

A pair of within spec Quad IIs and ESL57s is a classic and sublime combination which Peter Walker designed to be used with each other. Certainly none of this 'clipping, limited extension, pipe and slippers' rubbish. Certainly not a case of the amp 'struggling'. There may well be a better modern amp to improve on these speakers but I cannot think of one. Certainly not a Quad 306 (the ESL63s were initially designed to be used with this amp).

 

[Julf]

if you put big fat slicks and low profile alloys on a vintage MG or whatever you are a bit of a cock in my book!

I have to agree...

 

[disco]

I have to agree...

You have to use what is available, but if you put big fat slicks and low profile alloys on a vintage MG or whatever you are a bit of a cock in my book!

Conversely if you put radial tyres, pointless distibutor, 4 pot caliper disc brakes, uprated shock absorbers, replacement 5 speed all syncro gearbox and add power steering on a Jaguar XK150 not only will you improve the driving pleasure from that of a tank you will appreciably increase its market value.

 

[Marchbanks]

A pair of within spec Quad IIs and ESL57s is a classic and sublime combination which Peter Walker designed to be used with each other. Certainly none of this 'clipping, limited extension, pipe and slippers' rubbish. Certainly not a case of the amp 'struggling'. There may well be a better modern amp to improve on these speakers but I cannot think of one. Certainly not a Quad 306 (the ESL63s were initially designed to be used with this amp).

Conversely if you put radial tyres, pointless distibutor, 4 pot caliper disc brakes, uprated shock absorbers, replacement 5 speed all syncro gearbox and add power steering on a Jaguar XK150 not only will you improve the driving pleasure from that of a tank you will appreciably increase its market value.

So vintage cars and vintage hifi are not analogous, QED?

 

[disco]

Have a look at Hi-Fi Collective for several choices of carbon resistors, other similar retailers will have other alternates.

So I had a look at the Hi-Fi Collective website for original carbon resistors ie Allen Bradley types. Yes they do have a range of old stock as fitted to Leaks, Quads for which they are asking approx. £1.00 each. Tolerances are poor at either 5% or 10% but then they add a disclaimer saying that these tolerances may be exceeded due to the absorbtion of water which is a normal characteristic of carbon resistors. They continue by advising that they be dried in an oven for 8hrs at 80degrees C after which they should be coated with shellac to prevent subsequent moisture absorbtion. No guarantee is given as to the final tolerance acheived.
What do you think Peter Walker would have done? I think I know.

 

[disco]

So vintage cars and vintage hifi are not analogous, QED?

How do you come to that conclusion. I have stated nothing that should lead you to believe that I am against using modern components in reinstating equipment to meet its original design specification.

 

[Marchbanks]

It wasn’t a conclusion, it was a question. You think the answer is ‘no, they are’ I think?

 

[Tony L]

Personally I’d use modern carbon. In fact I hadn’t even noticed HFC had a stock of NOS Allen Bradley resistors. My point is to use the same component type, not necessarily the same brand. HFC have a couple of Japanese brands I’d expect to be very good.

I’ve no idea why folk are getting so entrenched and defensive on this one, I thought my perspective was standard conservation practice. I admit I have a very dominant collector gene, I come to audio as a record collector, guitar collector etc and apply much of the same mindset. I know my approach adds value too! I still view filling beautiful vintage Leaks, Quads etc full of modern film caps etc analogous to refinishing a vintage guitar. You just don’t do it unless you ate determined to trash the value, e.g. if someone rebuilt a TL12.1 or whatever with modern film caps, stuck an IEC mains connector on the back, an RCA socket on the top and some modern speaker outs on the back they’d have a great usable amp (albeit one that sounded brighter than it is meant to) but they’d also have knocked abut 50% of the value off compared to a very sympathetic and minimal restoration. I just want folk reading this site to grasp that point.

FWIW my working Stereo 20 is not a purist rebuild as I bought it after a previous refurbishment so some opportunities had been lost. It has modern RCA plugs, modern speaker sockets and whilst I went for the really nice Russian military PIO caps and modern carbon resistors in key locations there are a lot of modern metal film resistors elsewhere (I was advised to do this by someone with far more knowledge than I). I’ve hugely improved it and it sounds staggeringly good IMO, just so liquid, organic and natural, but it won’t be worth as much as the NOS one I can’t even turn on! It is infinitely better than the horrible botches one so often sees going through eBay:

It has since got some nice rubber feet (Quad 3-Series fit perfectly) and being more than a bit OCD the two blue electrolytic caps that protrude through the casing have been stripped, body-filled and sprayed in a matching bronze (a VW sand colour. IIRC).

 

[disco]

Looks like a Paul Greenfield (Classic Sounds) rebuild. I find nothing wrong in refurbing such an amplifier in this manner using modern components. As you say it sounds wonderful and gives you much pleasure and may even sound exactly as when originally made (or even better). If we are now talking in commercial terms obviously it won't be worth as much as a new old stock model notwithstanding that it has never been turned on. Similarly a tatty non-woking but truly original model is worth approx the same as a refurbed one such as yours. Again this is the inexplicable far eastern mentality (perhaps they enjoy doing the refurb themselves with components of their choice- who knows?). As an owner of over 20No vintage amplifiers (11 pairs of Quad IIs, Radford STA25, Capes, Connoisseurs, Armstrong A10s, Leak ST20, TL10.1, TL25, TL12+, TL12.1, PYE Mozart, Beam Echo DL7-35s etc) I choose to ignore this commercial aspect and just get them in a excellent working condition. Yes I prefer to use paper-in-oil capacitors as I have a large stock of the excellent ceramically sealed Russian military types. Saying that I have had excellent results from modern polyprops and I wouldn't dream of calling users of these, along with users of metal film resistors, bodgers or butchers. For me bodging is defined by poor workmanship, incorrect value components, unproven modifications to circuitry etc.