60's & 70's amplifiers

[joel]

PS Check this Luxman CL-32 preamp out; silver facia, tubes and a Quad style tilt control! What's not to like?

That seems expensive... The same thing is around 90,000 yen (about 800$ at current exchange rates) here with a one year guarantee, and a Baker Audio style refettle ;-) from the usual place.
There's also the A3032 which was the Luxkit version you could build at home! http://www.hifido.co.jp/KWA3032/G1--/P/A10/J/0-10/S0/M0/C15-86155-38380-00/

 

[Tony L]

There is a requirement for rebuilding old amps, possibly replacing like for like with new. However indiscriminate application of this may not be the best thing, as I said with my JVC just a few tired caps replaced made a huge difference.

If an amp was rebuilt with 100% new parts then there would be no issue but that's not practical

I don't quite follow you. I see no issue aside from cost, which doesn't bother me as electronic components tend to be pretty cheap in the grand scheme of things and these days I can do most of it myself. As an example my 34/306 has every single electrolytic cap replaced (by Rob) and I'm mid way through replacing every single resistor and capacitor in my Leak Stereo 20. They'll all likely see me out, whereas i suspect your JVC may need another service within 5 years or so. Given the choice I'd prefer just to get it all done as well as possible from the off. I've also just fully recapped a tube preamp I bought second hand recently as i didn't know it's history and again wanted the peace of mind knowing it was as good as new and I don't need to think about that aspect again for well over a decade. It cost me about £23 quid in electrolytics so no big deal. Far better that than risk damaging any expensive and rare NOS tubes etc. it may just be me but I find i can relax and enjoy kit more once it's fully restored. There's no nagging feeling something might be a bit 'off'.

 

[Patcam]

I'll have to keep an eye on the market and maybe reconsider my recent announcement on the matter if there seems enough interest
I just can't see people being willing to pay £350+ to refurbish an amp they won on ebay for £70..... especially as they would probably get say £200 for it if they re-sold it....

I well remember the dark ages of flat earthism when 8 year old range topping Japanese amps were going for £30!

Thing is, would the £70 amp and the £350 refurb - £420 in total - sound better than a modern, brand new amp costing the same outlay? What can you get for £420 these days? Would the CR 2020 selling for £750 on that site outperform a new amp costing the same? I suspect it would. An interesting comparative review for one of the hifi publications!

 

[PaulMB]

The capacitor thing is food for thought. My main issue as a punter is that if I'm paying a good wedge for a service I'd want the job doing to the extent the item was done for 10-20 years. I'm perhaps over-paranoid/way too OCD in this respect, but when I restore a piece of vintage kit (either myself or paying someone else to do it) my aim is to make the item as-new again, e.g. I consider myself to have a brand new Quad 303, 34 & 306, a brand new pair of JR149s etc. Getting it done right is my only priority. I can take this line of thought too far (e.g. TD-124!), but it's just how I work.

PS Check this Luxman CL-32 preamp out; silver facia, tubes and a Quad style tilt control! What's not to like?

Just out of curiosity, but have you ever worked out how much you spent on the 124? I remember following the process a couple of years back with awe and envy.

 

[Martyn Miles]

I have given my Sony TA-F6B a long listen using the MC Phono input and found it is much better than the one on the previous amplifier, an Audiolab 8000A.
The Audiolab is an excellent amp. but mine was a little 'long in the tooth' as I'd had it 12/13 years and it was secondhand when I purchased it.
A man who services amplifiers bought it from me a a reasonable price and then serviced and sold it.
M. Miles.

 

[flatpopely]

I don't quite follow you. I see no issue aside from cost, which doesn't bother me as electronic components tend to be pretty cheap in the grand scheme of things and these days I can do most of it myself. As an example my 34/306 has every single electrolytic cap replaced (by Rob) and I'm mid way through replacing every single resistor and capacitor in my Leak Stereo 20. They'll all likely see me out, whereas i suspect your JVC may need another service within 5 years or so. Given the choice I'd prefer just to get it all done as well as possible from the off. I've also just fully recapped a tube preamp I bought second hand recently as i didn't know it's history and again wanted the peace of mind knowing it was as good as new and I don't need to think about that aspect again for well over a decade. It cost me about £23 quid in electrolytics so no big deal. Far better that than risk damaging any expensive and rare NOS tubes etc. it may just be me but I find i can relax and enjoy kit more once it's fully restored. There's no nagging feeling something might be a bit 'off'.

Hi Tony.

I may do mine for piece of mind just like you, but my JVC AX-Z1010TN currently shows no signs of any issues. DC at the spekars is less than 1mV and the idling current measurement is on the nose too at 10mV, it's a very healthy amp.
Oh and it sounds ace too.

 

[Tony L]

Just out of curiosity, but have you ever worked out how much you spent on the 124? I remember following the process a couple of years back with awe and envy.

I don't dare total it up as it would annoy me too much. I know I'll take a substantial hit when I sell it (which I'm seriously considering as it's just sitting around doing nothing at present!). It's a stunning deck, I just don't have a context for it at present as ultimately I prefer the 301.

 

[kings1]

I love my Lp12 until I upgrade to a Michell orbe

 

[Martyn Miles]

I love my Lp12 until I upgrade to a Michell orbe

Funny amplifiers (?!)

 

[istari_knight]

I find blanket recaps therapeutic Of course you have to be sensible about what you're replacing, just throwing in the most expensive parts you can find is a recipe for disaster but if you intend to keep said amplifier long term its foolhardy not to do it/get it done IMO.

I've got an SU-V7 on the operating table today, the output relay is pitted beyond repair and the main reservoir caps have spewed their guts but thankfully Technics included a small hole beneath each cap in the PCB allowing the fluid to drain away... Now thats good design Figured as I'm in there I may as well replace the other 26 caps, IME lifting tracks etc is a complete non issue on anything other than the poorest quality equipment - I've worked on hundreds of amplifiers, its happened twice and both times were due to my own negligence.

FWIW the total cost of components was £19.96... For a refurb to cost upwards of £300 the tech must be charging no less than £50 an hour.

 

[Tony L]

Figured as I'm in there I may as well replace the other 26 caps, IME lifting tracks etc is a complete non issue on anything other than the poorest quality equipment - I've worked on hundreds of amplifiers, its happened twice and both times were due to my own negligence.

Some kit is notorious for it though, e.g. Quad 33, 303, FM3. I've seen examples back from proper in-house Quad servicing with repaired tracks as they've obviously lifted. It's the main reason I went all-out on a full set of Dada Electronics 'High-End' boards for mine (nice modern glass fibre boards already populated with decent quality components so an easy service!).

 

[dim_span]

Wondered if it was bollocks! Seem very sure of themselves, what with anything with an ic being rubbish etc etc

Discovered they want 750 quid for the CR 2020...think it's worked out at 400 for an original amp and 350 for their refurbish and upgrade. Worth it?

I contacted them a few weeks ago as regards the CR2020 ... he wanted £800 for it (it never had a price when I viewed it)

I also enquired about the CA1010 which they still have to refurbish, and he could not give me a price but said that it would be more than the CR2020

I'm after an old Yamaha .... they charge approx £300 for a service but what worries me is will it be returned to original spec? It's pointless having an older good amp that does not perform like the original (thats why I ended up selling my old Pioneer SA-9800 .... I could not find anyone in the UK who could get the original caps etc .... Echowars in the US is good for Pioneer but he is too busy, and waiting times are long

 

[Robert]

The capacitor thing is food for thought. My main issue as a punter is that if I'm paying a good wedge for a service I'd want the job doing to the extent the item was done for 10-20 years. I'm perhaps over-paranoid/way too OCD in this respect, but when I restore a piece of vintage kit (either myself or paying someone else to do it) my aim is to make the item as-new again, e.g. I consider myself to have a brand new Quad 303, 34 & 306, a brand new pair of JR149s etc. Getting it done right is my only priority. I can take this line of thought too far (e.g. TD-124!), but it's just how I work.

PS Check this Luxman CL-32 preamp out; silver facia, tubes and a Quad style tilt control! What's not to like?

I suppose my comments are more aimed at DIY enthusiasts or collectors of older gear, and is intended to allay some of the fears around using such kit without having every electrolytic replaced. My point is that most of this old stuff works just fine when cleaned-up and de-oxed, re-adjusted in the case of amplifiers and then enjoyed. Sometimes the odd cap has failed and there are usually visual clues.

For someone wanting to pay top dollar for a complete overhaul to keep kit working for another 30 years, I agree there is an argument for comprehensive servicing, especially for classic kit of value.
This also needs viewing alongside costs. If you buy a nice little Japanese amplifier (like the AX3 Andrew has) for <£100 it's often just fine to give the thing a good clean and use it. To rebuild the thing, likely making it perform no better, can cost 3X the purchase price.

FWIW official Quad servicing always had a policy of replacing only faulty parts. I've seen old 405 amplifiers where the original 80s main caps are still in place, but 2-3 small caps on the boards have been replaced (confirmed by the usual Quad service sticker). No idea if AIG still adhere to this policy. I wonder if the 'replace all caps' is a hi-fi thing since as a kid I recall when our 20+ year old TVs broke down, the TV Repair Man (remember them?) would arrive and perhaps swap out one part.

Nice Luxman

 

[Patcam]

I contacted them a few weeks ago as regards the CR2020 ... he wanted £800 for it (it never had a price when I viewed it)

I also enquired about the CA1010 which they still have to refurbish, and he could not give me a price but said that it would be more than the CR2020

I'm after an old Yamaha .... they charge approx £300 for a service but what worries me is will it be returned to original spec? It's pointless having an older good amp that does not perform like the original (thats why I ended up selling my old Pioneer SA-9800 .... I could not find anyone in the UK who could get the original caps etc .... Echowars in the US is good for Pioneer but he is too busy, and waiting times are long

Didn't have a have a price on the website when I first looked - I emailed him to find out and they told me £750. He says he upgrades the various components so the amp is better than the original - eg. a different psu as the original one caused drastic overheating problems in all CR20xx.

I guess the only way to find out is to actually buy it... no guarantee, but he promises to 'help' the new owner down the line if anything goes wrong.

 

[dim_span]

Didn't have a have a price on the website when I first looked - I emailed him to find out and they told me £750. He says he upgrades the various components so the amp is better than the original - eg. a different psu as the original one caused drastic overheating problems in all CR20xx.

I guess the only way to find out is to actually buy it... no guarantee, but he promises to 'help' the new owner down the line if anything goes wrong.

Alarm bells rang when I read that it is better than the original ....

sort of reminds me of buying a really good classic car in original condition, then changing the exhaust to a boy racer exhaust .... or replacing the engine with a totally different engine

I've been eyeing the CR2020 on ebay for £420 .... in original condition, and I was tempted to make an offer ... I'm also after NS1000M speakers to match

 

[Arkless Electronics]

IMHO a total re-cap is warranted for peace of mind and to be sure that the equipment is working at its optimum. There can be quite a difference between a cap that works and one that works at its peak performance.

It is perfectly possible to rebuild an amp to be better than new and this is something I often claim when I do rebuilds.
Electrolytic cap technology improves continuously and often it is possible to (for example) fit 15,000uF smoothing caps in the space occupied by the original 4,700uF ones.
Manufacturers usually fit what is adequate, to keep costs down, rather than what is best and I usually fit 105C rated, low ESR, long life electrolytics rather than just the same lower spec parts fitted originally. Modern advances such as Oscons and polymer caps can also be fitted to sensitive parts of the circuitry. I often also replace older type op amps with better modern ones.

Testing caps is as time consuming as replacing them, and as so much labour is involved with getting access to boards in many instances it makes sense to change them. If an amp is 25 years old then just cos a cap seems ok now doesn't mean it's not going to be below par in a couple of years time

The make and model of amp and the way it's used can have a huge impact on cap life as well.... I have had amps in that run quite hot and have been left on 24/7 in which virtually every electrolytic cap had failed. Usually with no visual sign but very much a dud when tested on an ESR meter! A Krell integrated comes to mind here... I re-capped one a couple of years back in which every cap other than the smoothing caps tested dud! Yes it had been on 24/7....

 

[Arkless Electronics]

Thing is, would the £70 amp and the £350 refurb - £420 in total - sound better than a modern, brand new amp costing the same outlay? What can you get for £420 these days? Would the CR 2020 selling for £750 on that site outperform a new amp costing the same? I suspect it would. An interesting comparative review for one of the hifi publications!

That is a very valid way of looking at things yes and I have had customers who take that view point. If one has no plans to ever sell on the refurbished amp then I suggest that is the best way of thinking about things...

 

[flatpopely]

Jez.

What are the audible and measurable signs the caps are going off?

My amp measures bang on for DC offset and idle bias plus it sounds ace. Is this enough for it to be ok?

 

[Arkless Electronics]

Jez.

What are the audible and measurable signs the caps are going off?

My amp measures bang on for DC offset and idle bias plus it sounds ace. Is this enough for it to be ok?

It is very unlikely indeed that idle current or output offset would be effected by caps going off.

Effects of degradation in electrolytic caps very hugely depending on the design of the amp, which caps are dodgy and just how dodgy they in fact are!
It can vary from nothing being noticeably wrong.... but a re-cap shows that there was more performance potential in the amp and it was being held back by caps that just weren't quite up to full spec.... to a range of weird symptoms and very measurable issues if the caps (or some or even one cap) have become totally out of spec.

 

[John]

Here's a Yamaha CR-2020. The idea of replacing the caps in something like this amp looks like no easy feat but if I were to go through the trouble of pulling this apart to get at a couple capacitors, I'd go ahead and replace them all. I certainly wouldn't want to have to pull this apart again!