Building the Audio Note Kit 1 SET amp...

Rebbi,

Where in the circuit are the caps C1 thru C4? Since the silk screen on the board shows a physically much larger size cap for those four, did they modify the original circuit or simply send you the four mylar caps by mistake. Good luck, you're in the homestretch now!
Ron

Jet, you are so right and I so do that! Let me share with you my most recent find for the power supply of tube amps and preamps. I have used the large computer grade electrolytics and recently tried the oil types from GE & ASC. I like the oil types and have mixed them with Mundorf MLytics when more capacitance is needed.

However, nothing prepared me for the sonic breakthrough that resulted when I placed 100% Clarity TC film caps in my Preamp. Oh my. Go look at Parts Connextion and see the TC 600 series of film power supply caps. With no electrolytics in my preamp and these killer TC caps things really opened up and the life like sound of voice and instrument is SOTA.

They are large and you need room under the hood so some gear won't accommodate them unfortunately. TC caps come in 600vdc values with up to 500uf of capacitance. They simply sound spectacular. Since my preamp is tube voltage regulated, and I cannot overstate the importance of tube regulation done right, I was not sure how much these TC film caps would help over the computer grade electrolytics. The bottom line is they are really a sonic joy.

These are the sorts of improvements only DIY initiatives and curiosity will uncover. Since starting my DIY journey I am happy to say the sonic gains in my system are unprecedented and I have learned so much.

Lots of great gear out there designed by brilliant folks and companies. They can often times be brought to the next level with DIY initiative and passion.

Ronnjay, here is a Kit 1 schematic which I believe corresponds pretty closely if not exactly to the configuration supplied to Rebbi. (See page 3 of the pdf for a clear presentation of the schematic, although you will have to refer to the first two pages for the reference designations of the components). As you will see, C1 through C4 provide noise filtering and decoupling for the B+ that is supplied to the small signal stages.

Consistent with Rebbi's explanation of the reason for the two holes and pads at one end of the capacitors, it appears that some versions of the kit were provided with physically large 0.015 uf capacitors (see Section 7 of the manual), and others (including Rebbi's) with smaller capacitors which are 4700 pf according to the schematic. Both values seem to me to be within reason, with the choice depending on the range of frequencies that are considered to be most likely in need of being filtered.

Rebbi & Mapman, thanks for the nice comments.

Best regards,
-- Al

Almarg,
Right. If you go to the product page of the Kit 1 8th anniversary edition (not the C-Core 10th anniversary edition) and you click the download manual tab at the bottom of the page, you'll find photos in the manual of the populated driver board, using the older style, much larger caps. They would have used the top and bottom holes. The smaller sized caps being delivered with the kit these days for C1-C4 use the middle and upper holes, as Al pointed out.

On another note, Brian and I did more testing last night via Skype and confirmed that there are some very wonky AC voltage values on my driver board, so something is wrong there. That seems to be the source of the sonic problems I've heard! It's not impossible that I have some bad solder joints connecting the valve bases to the PCB, so I'm going to go through those and see if adding solder fixes the problem. But in the meantime, Brian is having Digital Pete, his builder in Florida, send me a finished driver board to replace mine in case I can't get mine sorted. I think the one he's sending has the standard Mundorf Supreme caps, but if the board fixes the problem, I'll replace them with my Silver/Gold/Oil caps.

Again, AN Kits customer service has been above and beyond. Although I'll have to swallow some pride to use Digital Pete's driver board in place of my own if I can't get mine sorted, it'll be a quick way of getting the amp in order!

I have enjoyed this thread more than any I can recall here on Audiogon. The comments by Jetrexpro, Grannyring, and others ( and the incomparable insight contributed by Almarg), gives so much validity to the DIY approach.

Even though my skills pale in comparison to those mentioned, my sense of musical enjoyment would be greatly impaired without even my limited DIY minstrations.

Which is why this thread is so enjoyable. I think back on some of my own projects, which all seemed to come with their own set of problems, mistakes, and mishaps, it seems to add to the overall audio, and DIY, experience.

I wouldn't have it any other way.

My very best regards to all,
Dan