Audiolab 8000A recap and mod

[Fulci]

Hello everyone!


I am thinking of recapping my Audiolab 8000A, series C, as it is already 20 years old. It still performs nicely, but sometimes I feel there's something missing, and I guess I take so much more out of this amplifier...

I can't find any good schematics for this amp, only for the Power section.

So, I am thinking of performing the following mods. I'd like if you could kindly give an opinion on these tasks and tell what else could I change, and if has anyone performed any mods on an Audiolab like this one.


1. Replace the 10.000uf 50v Elna PSU caps for new ones. I will be using 10.000uf 63v, but can't decide wether to get KENDEIL K05 or MUNDORF MLytics AG. Has anyone compared these or can give an opinion on which should be better?
Can I use 15.000uf and would I get any improvement on this? And are the Kendeil selling on ebay fakes?

2. Replace all the Elna Starget and RE2 in the Pre (and Power) sections with ELNA SILMIC II (or NICHICON MUSE - again, what do you recommend here? Looking for PRaT and definition, don't mind a little coloring)
What is the difference between the Stargets and the RE2 and why did they differentiate these?

3. Bypass the PSU caps with a film MKP1839. I think there is already a bypass cap here, though I can't see which one, or it's value. If there isn't any, will I get any improvement placing these?

4. Should I change the EVOX MMK caps, in the pre section (or is it tone control?) with better ones? What do you recommend as a better cap to use here? Should I do the same for the power section (there are a lot more here than in the pre)

5. Replace the 22pF Polystyrene caps (transparent, tiny) in the tone control section for Silver Micas. Any idea of anything better to try here as well? Some film caps maybe?

6. Change the blue film caps (EVOX PFR, I think)? There are a lot of these, so lots of work. If it's not significant, I won't bother. Are these any good, or is there better to think of?

7. Change internal wiring, maybe. What do you recommend to place here? I might try speaker cable maybe, like Van Damme or Sommer, or maybe silver wire?

8. Place new RCA plugs with silver wire and remove the ones unused. The original are cheap plastic, a few have already fallen off.


So, sorry for such a long post and thank you all in advanced for all the help you can give. I am looking to have a bit more PRaT and musicality out of this amp, but also warmth and better depth, definition and separation. I am aware that this amplifier was originally a bit sterile, even though warm, but I can make this happen.

I will post pictures of the internals later if needed.

[jostber]

Might be a couple of useful links here:

http://www.diyaudio.com/forums/solid...lab-8000a.html
http://www.hi-fi-insight.com/audiola...amplifier.html

[DSJR]

I can't for the life of me remember the service/dealer, but "Audio Cellar" stays in my memory....

An online-mate of mine has had a later "black" 8000A refurbished along the lines you speak of and really rates what has been done to the sonics compared to the otherwise ok sound previously.

UK made Audiolabs must be ripe for bodging now since the newest are around fourteen years old at least. I wonder just how different the current Chinese ones are, or have they suffered with inferior electrolytics as Quads have been - reportedly?

[Dingdong]

I'm not sure you are going to achieve what you want by changing all the caps. It will probably sound a bit different, but different in the way you want? Who knows.
Have you considered a change of amp? Then you could find one that did give you the sound you want.
But if you like the idea of recapping then go for it. I recapped an amp a few months ago for a friend. It did improve the sound a little bit, but not really the nature of the amp.

And be careful buying cheap caps on ebay. Especially from China/Hong Kong.

[Fulci]

Thank you all for your kind replies.

This amp must be around 20 years old, so it's in need of a recap. If I can use better components and further improve it's sound quality, the better! I don't want to make it sound like a Naim, but I do wish to fine tune it to be a bit more musical and three-dimensional. (I will some day buy a NAIM amp, by the way).

I got the Audiolab for £150. If I spend another £50 to recap it, modding and fine tuning it, I am sure it would compete with machines costing way above £500. That meaning that I'd need at least an amplifier costing £1000 to be worth replacing it. For £200 I think it's a bargain.

I am trying to get as many ideas where to improve it as possible. I found a chinese forum with many options. But it's in chinese, and I can't open the pictures. You use google to translate it.

http://hififever.com/discuz/viewthread.php?tid=1244


Also, Red Hill Audio has a few options to upgrade and mod Audiolabs. This is what I want to do, but I just don't want to spend £240 doing this, and specially I don't want to send this to the UK, as it'd be another £60 in post.

http://www.redhillaudio.co.uk/audiol..._upgrades.html

So, they state, and I quote:

F&T Cap Audio Grade smoothing capacitors for improved bass grip and definition.

Will place Mundorf or Kendeil here. Mundorf are F&T, but I've found this for the same price, no problems here. Kendeils I found in ebay comming from Italy, just checking if anyone has any idea if they are trustworthy. I'd really like to know what should be the best from these two.

Panasonic FC Low ESR, Rubycon ZA/ZL Low Impedence decoupling capacitors improve transient response.

Using ELNA SILMIC II (or NICHICON MUSE) instead of the pannys. But I can't seem to find which are the decoupling caps, and why using Rubycons, or what else to use here.

Sound-destroying signal-path electrolytic capacitors replaced with low-noise, low-distortion film types improve all aspects of the sound. Detail levels are improved and the sound becomes smoother and less grainy.

Which one are these, and what are they replaced with? I read somewhere film types are not that much of an improvement over the SILMIC, not at least counting for their cost and size. But curious about these, and if there is at least a couple or two that could be changed that are worth the cost.

We can also replace the phono sockets on your amplifier at a small extra cost, please ask for details.

Ok, sometime later.


The Ultra Upgrade states:

Greatly improved components for preamp section gives more detail and better dynamics.

Which one are these? The white EVOX MMK and the polystyrene?

Additional decoupling capacitors added for lower noise gives better separation of musical layers.

Again, what, where, which?

Key transistors changed for improved sound quality and a more fluid soundstage

I'll check these later on...

Red Hill Audio "Supreme Discrete Voltage Regulator" added to preamp power supply for vanishingly low-noise levels brings much more musical information, better tonality to instruments and more realistic and natural sound.

Not touching this... Way out of my league... but would be interesting too...

[DSJR]

Hang on a minute - many/most valve amps wouldn't work at all without electrolytic coupling caps here and there. Nothing signal-destroying about Nichicon Muse types IMO, polarised or non polar...

Many forty year old amps don't need their caps replacing - it just depends how they're loaded - or not - so please don't automatically assume the 8000A will need wholesale bodging as a matter of course, 'cos I guarantee it won't.

You know, after all the money you've nearly spent, I'd almost be inclined to flog it as-is, and replace with a UK made 8000S or, better, an 8000Q and 8000PX or monos of any vintage. Use smooth sounding interconnects as short as possible and sensible copper stranded speaker cables of good gauge with these for the safest sonic performance..

[Fulci]

It's not that much money really... a couple of PSU caps go for under €20, and all the ELNA SILMIC IIs won't cost me €20, if I don't touch the phono section (don't need it just yet). Not spending much more really, Silver Micas and a few MKPs won't cost me much, so if I spend as much as £50 with this it'll be too much. And won't pay most of the fun for doing this.

Buying a power amp, even if a 8000P, it'll cost me at least another £200 minimum...

For that, I'd get a Naim or Exposure. Or even a Rega...

[DSJR]

Found the link if you haven't done so already -

http://www.theaudiocellar.co.uk/

[Fulci]

Thank you for the link, Dave.

I did see them before, but like I said, I don't want to send it back to the UK, and it's something I want to perform myself.

[ml_c2]

Hi,

Did you make any of the mods to the Audiolab and if so, what were the results?

thanks
Malcolm