PP-KT88 Kit Opinion

[timolien]

I've been looking around on this site and others to make up my mind about what I want to build.

After (lots) of time I think I settled for a tube design and more in particular a KT88/6550 based PP design.

PP because of the not to high efficiency of my loudspeakers (86 dB MTM design with 2x Scanspeak 15W8530 and a SS 2904/9800, complemented by a suitable sub)

KT88/6550 seems to be a long time audio favourite.

I opted for a kit because all parts are delivered at once, there should be a fairly accurate description and the different parts should be "compatible"

I found the following possibilities on the net :
All are from Europe : shorter shipping distance, easier for customs

http://www.ampdesign.de/Bausatz.htm :
EUR 750 + shipping

EUR 1000 - 1250: http://www.worldaudiodesign.co.uk/wadproducts/kit6550.html :
basic : £580.00, shipping : ?, taxes : included
several upgrades possible, amounting to 250 EUR

EUR 1200 - 1975:
http://www.velleman.be/ look for K8010 :
all in : EUR 1200
several upgrades possible, amounting to 775 EUR

EUR 1500 : http://www.diyparadiso.com/ppkt88mono1.htm but not the mono blocks but the integrated stereo amp based on same components

There will certainly be others.

Is my idea of going for KT88/6550 PP any good ?
Is someone able to give me advice on which kit would be best ?
Where does the price difference between the kits come from ? Better (passive) parts, better transformers ?
Any positive/negative experiences with any of these (or suitable others) ?

Gert

 

[Brett]

Hi Gert,

<b>Is my idea of going for KT88/6550 PP any good ?</b>

Yes, I think so. However looking at the info on some of the designs you listed, there is quite a difference in power, sensitivity, integrated or stand alone etc, so you need to decide what you want.

Based on a quick look at the manufacturers sites, I like the look of the diyparadiso design best, esp for triode, but I think this puts out the least power, in triode, but switchable UL mode is an option to get you to 50W if you want to rock out. If you <i>really</i> need more grunt, go for the Velleman (cheaper too).

Ideally, try a similar PP tube amp with your speakers to get an idea how much power you really need.

Also, if you're an experienced builder, then you could do one for less than most of the ones you mentioned by building from scratch. If not, then the kits are a great idea and a simpler and quicker process.

I can't comment on the sonics of them, though I've built designs similar to the diyparadiso.

HTH some.

 

[fdegrove]

OPINIONS.

Hi Gert,

Never was impressed with any Velleman design, too many corners cut.

Benny has a nice kit, it's close to home too you and I'm very much convinced Benny cares a lot more than he'd he'd care to admit.
My first choice since you can establish real contact with him whenever in trouble...after all he's just around the corner.

The other kits may be great too, but you'd be pretty much on your own.

If ever you may want to improve on whatever you pick you can always post back here and I'm sure all dyed in the wool DIY'ers will flood you with do's and don's.

Cheers,😉

 

[valveluver]

PP 6550

The 6550 has good specs. @60 watts out the specified harmonic distortion is 0.6 percent with no feedback.

 

[siu sin man tho]

hi,

for the cheap nos tubes use in your kit, pls try to consider the NOS GEC TT21, this was the top cap tube but same spec as GEC or Gold Lion KT88.
Many User of KT88 in hong kongf like to use this tube to relief
KT88.
Pls go to ebay to search. quite cheap.
But top quality.

thanks

Thomas

 

[robbie]

hi
i have the world audio design kit88 which has now been replaced with the 6550model in your link. there is a bb conected to the wad site and there are people that not only willing to help but have tried out many mods and prepared to pass on their findings.
i know i have a bias but would /and have bought from wad again.

rob

 

[papparazzi]

I am playing with Boully Kt88 Integrated and very Satisfield .In that price Transformers are Lundahls . Triode mode is not enough for such sensivity. I play 92 jordans (87 db ) in modest volume levels with 25 watt triode .UL solves the problem but not soundin as good

papparazzi

 

[timolien]

In the end I went for the Boully too.

As a matter of fact, I have the very first one made.

I am very satisfied with it, although it can't play very loud with my speakers since it's wired in triode mode. Don't know how many Watts are left, but who cares as long as it sounds as it does.

Hope you're satisfied too.



Gert