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KT88 SE Complete Kit

Hi,

I have been running my stereo KT88 SE for about 10 months now at a minimum of 50 hours per week. The amp is switchable between triode and ultralinear operation, so I have probably run it about half-and-half in each mode. That's about 40 weeks X 50 hours = 2000 hours. The voltage/current measurements have not changed. No blown fuses. Absolutely no audible hum at idle or during operation.

The audio presence, staging, separation, clarity, etc. are phenomenal. I designed and built a set of 98dB ported-enclosure, 2-way loudspeakers using a horn tweeter that I'm sure account for part of the excellent audio experience that this amp offers.

Would there be any interest in a complete parts kit for this amp? The kit would include:

1) Pre-punched/drilled top plate.
2) Aluminum chassis to drop the top plate into. This could possibly be a wood chassis, or not included at all.
3) Custom power transformer, power supply chokes, 4lb. output transformers.
4) All resistors Vishay metal film with the exception of the KT-88 cathode resistor, Caddock non-inductive film.
5) Capacitors - Ampohm & Panasonic motor-run metallized polypropylene filter caps, Auricap coupling caps, Elna Silmic II cathode caps.
6) Neutrik panel-style RCA input jacks.
7) IEC power entry module with EMI/RFI filtering and fuse module.
8) Custom turret boards for components.
9) (2) KT88 & (1) 5U4GB Electro-Harmonix tubes, (1) Soviet 6N1P-EV
10) All tube sockets, hardware, silver connecting wire, ground lugs, etc.
11) 100V, 120V, or 230V AC power input.
12) 4, 8 or 16 ohm output.
13) Complete instructions.

This amp uses NO silicone semiconductor devices whatsoever.
No volume control is included but could be added.

The only thing required by the builder would be: solder station, solder, and soldering skills (required for a successful build), a #1 & #2 phillips screwdriver, a 1/8" flat-blade screwdriver, a 5/16" & 1/4" nut-driver, and a small adjustable wrench.

Please let me know if this is something that folks may be interested in.

Sincerely,

Scott
 
Pix and pricing???

I can definitely work up pricing in a few days if there is enough interest, however the pix may be a bit difficult for what I envision as a final product. My current amp was built on a Hammond aluminum chassis using Hammond power xfmr & choke, and Mars output xfmrs. I can provide a pic of my current build however it does not represent what I would provide as an end product. I could provide an artist rendition of the final product as I see it.

In the meantime the attached photo shows what I have. The new power transformer and choke would be similar in appearance and mounting to the output transformers shown. My current build used (4) electrolytics for the KT88 B+ in a series/parallel configuration with balancing resistors to achieve the voltage rating for initial voltage surge at power up. These would be replaced with Panasonic metallized polypropylene motor-run caps to avoid the whole balancing resistor debacle.
 
I can definitely work up pricing in a few days if there is enough interest, however the pix may be a bit difficult for what I envision as a final product. My current amp was built on a Hammond aluminum chassis using Hammond power xfmr & choke, and Mars output xfmrs. I can provide a pic of my current build however it does not represent what I would provide as an end product. I could provide an artist rendition of the final product as I see it.

In the meantime the attached photo shows what I have. The new power transformer and choke would be similar in appearance and mounting to the output transformers shown. My current build used (4) electrolytics for the KT88 B+ in a series/parallel configuration with balancing resistors to achieve the voltage rating for initial voltage surge at power up. These would be replaced with Panasonic metallized polypropylene motor-run caps to avoid the whole balancing resistor debacle.
 

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Schematic, Pricing, Pics

Hi folks,

There appears to be some interest in this project.

Please give me a few more days to complete the pricing. I'm still waiting on vendor pricing for the transformers.

I will post the schematic probably by the end of next week.

Just an FYI, the amp is a variation on the Abdellah design with a few modifications.

Thanks.
 
The amp is around 5 - 7 watts in triode mode and a little over 10 watts in ultralinear mode.


whats the approximate power output of this amp?
Im slowly learning but dont have the knowledge to know if figure that out yet...
I might be interested in a kit, its a nice looking amp!
it also depends on pricing as well... so approx price would be nice :)
 

najo49

Member
2010-10-23 3:58 pm
I am very interested in you SE KT 88 kit. Could you keep me in the loop and let me know the particulars as they unfold.You could count on me to act quickly if this continues to look as good as it does with the little info I now have. Thanks for you consideration. Jan Olsen
 
Looks good! I've been running the Abdellah amp for over two years now and am very happy with the sound. Nice to be able to roll different tubes also.
It's nice to see someone offering this in kit form as it's a good beginner project. Some people are a bit put off by the fabrication/metalwork aspect, it should sell pretty well.

You should add an option to use LED bias on the driver, after I switched my build to this I won't go back to RC. Just my preference, but a lot of people I've talked to prefer the sound. It would be a simple option to the kit.
JMTC

Glenn