KiT88 Upgrade Recommendations

[Richard]

Yes agreed, Jazz's proposed path is spot on for a lively amp but I think the risk is you'd do a lot of work then find it had been tipped over the top.

Before anything else I'd do the valves. From memory the JJ and Gold Lion KT88 re-issues are both good clear and lively. If those JJs are the originals swapping them out would be my first job (2000 - 3000 hours lifespan) then take the next steps if needed. A change of small valves can make a good difference.

Next up would be the electro caps as they will be getting tired and need changing for reliability at least. The Epcos RS 496-2198 look good for C1/2 then Panasonic FC RS 315-0552 for C9/10/11/12 and FCs too for the others, don't be put off by the cheap prices.

[Black Stuart]

Hi Jaz,
nice to see you are not rushing into anything. I see that your PSU has BC/Philips LL caps, as you hav'nt used this amp for years and as they are long life, they may not need changing for a few years yet. There was a lot of hype over BG caps, so no loss there. I use the BC/Philips now for preference.

Richard is right, the Orange drops are not bad at all, like a lot of others on this forum I rushed in and bought the AN PIOs, if you like a warm slow,squishy bass sound they are fine, same goes for all PIO caps.

I'm not knocking this old sound but you either like it or you don't.

Comments about what kind of speakers you have (or are likely to have) are good because it is all about 'synergy'.

Z foils are not exotic they are made using an entirely different process which is more expensive, soon I'm going to replace all the RIAA smd resistors in my MC3 phono stage with Z foil ones because I know from practice that they are worth every penny. Certainly try the Maplins first to prove that the shunt mod is as good as many say then it's up to you - all the different carbons and metal films I tried were coloured, which means they masked in part the signal - not good.

I used to be amazed at how signal wiring was completely ignored or treated as 'not important' by so many in the audio world, now after 14 years of being serious about hi-fi I see how re-actionary so many are to 'change' almost religious/political in their intense resistance to change or adopt new ideas.

I see your i/c, it seems to be a variation on the Ven Haus design - I believe that most who tried this design abandoned it. It is important that you use bare wire inside of over size dialectric. PM me and I can tell you where to buy what you need.

I spent 4 years studying constructing ic/signal wiring - it can profoundly effect what you hear, not surprising since it carries all the info that you hear at the end of the system.

I cannot rec. multiple solid core conductors enough, nor the use of oversized FEP dialectric. The s/plated i/cs are completely neutral and the Mundorfs add a touch of warmth. These were tested by many in more than one country who confirmed by own findings - it's always nec. to hear the opinions of others. BTW use this type of i/c with a CDP and lose all or nearly all of the 'harshness' that so many complain about.

As per Heavisides proven work on electrical conduction do not use sleeving on any legs of caps or resistors. If you have soldered correctly there should be no danger of contact between components - heresy to the old school but a stone cold fact.

Silmic 11s are a bit bass light compared to the Silmic 1s. Do not be afraid to solder to the legs of existing components. Remember I used this simple technique on a h/amp - there is nowhere to hide using a good h/amp, never had a problem in over 5 years.

Power resistors - my rec. Mills far better than Welwyns - I'm not xenophobic - I'll take the best from anywhere.

Nice to hear your clued into active cooling, the re-actionary idiots still cling to ineffective passive cooling and it ai'nt cheap either.

A long post but it's nice to stop others from wasting money as I have done - information is everything.

[Black Stuart]

Hi Jaz,
I forgot to reply to your question about the Alps Blue - having used a quazi shunt on this pot for so long it was shock when I removed the Z foils - I simply could'nt listen to it as standard.

IMHO the Alps is fine when shunted, no need to waste money on exotic alternatives.

[jazlichy]

Quick question regarding values...

I've searched through several suppliers for my shortlist: Sylvania 6AU6's, Amperex ECC82's and Gold Lion KT88's, but I can't gauge how well these are matched from supplier to supplier. Could anyone recommend suppliers for close matching please? Some supplier don't mention matching at all! So far I've looked at Watford Valves for the Gold Lion KT88's, nostubestore.com for the Amperex ECC82's and Langrex for the 6AU6. Langrex stock the RFT 6AU6's, however I've not found Sylvania anywhere. Any pointers would be welcome.

Many thanks,

Jaz

[Ali Tait]

Look for GEC, made in same factory I think. Possibly RCA too.

[Desmodromic]

Originally Posted by jazlichy

Quick question regarding values...

I've searched through several suppliers for my shortlist: Sylvania 6AU6's, Amperex ECC82's and Gold Lion KT88's, but I can't gauge how well these are matched from supplier to supplier. Could anyone recommend suppliers for close matching please? Some supplier don't mention matching at all! So far I've looked at Watford Valves for the Gold Lion KT88's, nostubestore.com for the Amperex ECC82's and Langrex for the 6AU6. Langrex stock the RFT 6AU6's, however I've not found Sylvania anywhere. Any pointers would be welcome.

Many thanks,

Jaz

Derek at Watford Valves will certainly be able to do any matching you want. I've always found him very helpful and reliable.

[Richard]

Hi Jaz,

Yes Watford or Hotrox have matched KT88s http://www.hotroxuk.com/genalex-gold-lion-kt88.html

I can match you pairs of NOS boxed Sylvania (or GE or Brimar) 6au6. I also have used/bulk Amperex which test as new with matched sections, See the For Sale section of the bb (there were a dozen all same factory code so probably bulk stock rather than used as they all test perfect).

[jazlichy]

Thanks to all for responses on sourcing valves.

Richard I'll be in touch on PM.

Regards

Jaz

[Richard]

Thanks Jaz, PM returned.

[jazlichy]

Gents, quick question on cleaning valves pins on older valves? I'm guessing wire wool isn't a good idea in case it leaves wire fragments? Any suggestions please?

Thanks

Jaz