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KT 88 schematic search

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Hi to all. Iwas just wondering if any of you knew any good sites in which I can find schematics based on kt88's, be it PP or single ended. I am looking at building a new project and would like to build a power amp that will suit my Tannoy R2's. Not at the loud level, but at the clear level is prefered.
Thanks heaps
andrewe1
 
Andrew,
I looked up Tannoy R2
Nominally 4 Ohm and 90 dB/W/m sensitivity.

Single Ended KT88 will NOT cut the mustard - not enuf wik.

You should be looking for Zout of <= 0.8 Ohms and Power >= 25 Watts.

Don't be tempted into parallel push pull KT88s (4 tubes) - you don't need that much power and its about four times as complicated a a single pair of KT88s in Push Pull.

If you are in Melbourne give Scott Thompson a call at Rarefaction or look up his web site.

If he has stock he may be able to lend you a Chinese built TAD800 (Aus$1795) which is an integrated stereo KT88 Amp or a TAD500 which is very similar but with EL34 (Aus$1495). I recall him saying that he preferred the EL34 amp over the KT88 amp in A/B listening tests.

You will be very hard pressed to build an amp for these prices.

I've got one of the 20W per channel 845 SET Amps. The build quality and parts quality are fairly good and with a few minor mods and some front end tube substitutions this has turned into a very nice amp. Like all SETs a bit much 2nd harmonic distortion when cranked for my taste. I have seriously considered buying one of EL34 or KT88 Amps myself but am persevering with a 4 x KT88 with Plitron Transformers for now, having spent the money on the transformers I'm committed!!! Or should that be I should be committed for spending the money on the transformers?

Cheers,
Ian
 
90dB and power needed

Nominally 4 Ohm and 90 dB/W/m sensitivity. Single Ended KT88 will NOT cut the mustard - not enuf wik. You should be looking for Zout of <= 0.8 Ohms and Power >= 25 Watts.

Point is, I am currently mostly listening to my Heybrook Sextet speakers (less than 90dB/W/m) to my latest RH amp with KT88s (soon to be changed to 8417). The estimated power of the amp is in the 15W league, but even 10-12W WOULD CUT THE MUSTARD very nice, thank you very much.

Unless of course you need disco-club listening levels for parties attended by lots of friends (lots of dumping) in your 100m square living room... :)


Even some standard SE 300B amp with 8-9W of power would do! Don't be mislead by common "armchair knowledgeability" ideas.

Regards,
Alex
 
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