My first tube project help thread (NYD one bottle)

[gemini86]

Yes the output is 10k so a stepdown is required to feed 600 ohms.

 

[Kingston]

http://tubedata.itchurch.org/sheets/049/5/5965.pdf

http://tubedata.itchurch.org/sheets/093/1/12AV7.pdf

Pretty close...

ah, cool, those do look pretty close. Thanks for the links.

Did some re-reading in the original thread, and it looks like these work pretty well in the one-bottle, although some people found them noisier than 12aV7.

5965 and 5965A are drop in replacements. I was the one who originally said they were noisier. They are not. I said that when I was taking beginner steps, didn't know enough and my p2p layouts sucked.

I've since gotten to know these tubes a lot better, and from trying to source 12AV7 from around ebay, I'd say chances are most of the 5965 tubes you will find will actually be better quality than the 12AV7 that are still around.

 

[dustbro]

How do you guys feel about the sowter 9735 as an input transformer? Is it ideal or sufficient?

Ratio matches with the schematic, so it should work well.
Dave made a note on there that the prototype was built with a UTC O-11 which has a 150:15K ratio.
I guess any mic-to-grid transformer will do, but since you only have 1 tube to work with in the circuit, a higher step-up transformer would be helpful.
If you're ordering from Sowter, a 9705 would work for the output.

 

[dustbro]

link to a pic of the original NYD psu:

http://i261.photobucket.com/albums/ii49/aaronmoore82/NYDpsu_p01.jpg

In another thread about power supplies, someone suggested I check out the Pultec EQP schematic for inspiration. The CT for the heaters is fed HT which apparently makes things run with less noise. check out the schematic
http://www.recproaudio.com/diy_pro_audio/diy_files/eqp_1a/eqp-1a_schem.jpg

 

[buildafriend]

So a 1:1 turns ratio and 10k:600 or 15k:600?

 

[lassoharp]

No 1:1 for this particular amp.  It needs low to high then high to low impedance transformations.

 

[gemini86]

So to be clear, the output tx must be 10k:600 step down. at the least. That's a 4:1

 

[buildafriend]

http://tubedata.itchurch.org/sheets/049/5/5965.pdf

http://tubedata.itchurch.org/sheets/093/1/12AV7.pdf

Pretty close...

ah, cool, those do look pretty close. Thanks for the links.

Did some re-reading in the original thread, and it looks like these work pretty well in the one-bottle, although some people found them noisier than 12aV7.

5965 and 5965A are drop in replacements. I was the one who originally said they were noisier. They are not. I said that when I was taking beginner steps, didn't know enough and my p2p layouts sucked.

I've since gotten to know these tubes a lot better, and from trying to source 12AV7 from around ebay, I'd say chances are most of the 5965 tubes you will find will actually be better quality than the 12AV7 that are still around.

This Ebay seller is going to be annoyed with me. I asked him if I could have out of my winning auction for 5 single unmatched General Electric 5965A tubes. Then all of sudden I paid him and said send away.  :

 

[buildafriend]

So to be clear, the output tx must be 10k:600 step down. at the least. That's a 4:1

That did clear things up for me. I have never really looked at transformer impedences until this thread. I have always thought the only thing to pay attention for were turns ratios. and I should add, center taps and phase alignment dots..

 

[gemini86]

impedance ratio is turns ratio, squared.

so 10000/600 is 16.666(repeating)
sqrt of 16.666 is 4.082401254164024

... or 4 is close enough.

 

[buildafriend]

impedance ratio is turns ratio, squared.

so 10000/600 is 16.666(repeating)
sqrt of 16.666 is 4.082401254164024

... or 4 is close enough.

got it

 

[buildafriend]

link to a pic of the original NYD psu:

http://i261.photobucket.com/albums/ii49/aaronmoore82/NYDpsu_p01.jpg

the link should work, but if not, go to the NYD one-bottle thread, and use the forum search engine for "NYD PSU". I built my pair with this PSU (some values changed for feeding 2), and had some hum. moving layout around fixed most of it, but when I crack the chassis next time, I'm going to try a rebuild with more filtering. However, this PSU works fine, and the hum is really only evident at highest gain settings.

Re: input tx - cinemag is great... any reason that you're using the CMMI 7 instead of the CMMI 10? Strikes me that the higher step up should give some free gain, which could be handy if you decide to add an output tx.

Re: output tx - I used one (a gapped carnhill 9600:600 from audiomaintenance - I like it). The original NYD build didn't. The result of having one is less overall gain, but you can plug your one-bottle into whatever without reservations. Also, colouration can be fun. I think that max gain with an output tx was around 36db. Despite what I thought at the time, that's hasn't been an issue.

Re: reading - do lots of it. Read the NEETS stuff, read RDH, and most importantly, read up on how to safely work on tube gear. I've done a couple of tube builds, and I still go over safe working habits every time I think about opening anything.  300 VDC = no second chances.

Also, it's probably worth it to re-read the original one-bottle thread through. It meanders, but there's a lot of good info in there, and I'm pretty sure that eventually there's a revised schem that has an output tx, a DI point, and some different (optimized) parts values. A lot of it is stuff that many folks on here could (and did) figure out themselves, but I was definitely happy to have it on paper in front of me.

 

[buildafriend]

link to a pic of the original NYD psu:

http://i261.photobucket.com/albums/ii49/aaronmoore82/NYDpsu_p01.jpg

the link should work, but if not, go to the NYD one-bottle thread, and use the forum search engine for "NYD PSU". I built my pair with this PSU (some values changed for feeding 2), and had some hum. moving layout around fixed most of it, but when I crack the chassis next time, I'm going to try a rebuild with more filtering. However, this PSU works fine, and the hum is really only evident at highest gain settings.

Re: input tx - cinemag is great... any reason that you're using the CMMI 7 instead of the CMMI 10? Strikes me that the higher step up should give some free gain, which could be handy if you decide to add an output tx.

Re: output tx - I used one (a gapped carnhill 9600:600 from audiomaintenance - I like it). The original NYD build didn't. The result of having one is less overall gain, but you can plug your one-bottle into whatever without reservations. Also, colouration can be fun. I think that max gain with an output tx was around 36db. Despite what I thought at the time, that's hasn't been an issue.

Re: reading - do lots of it. Read the NEETS stuff, read RDH, and most importantly, read up on how to safely work on tube gear. I've done a couple of tube builds, and I still go over safe working habits every time I think about opening anything.  300 VDC = no second chances.

Also, it's probably worth it to re-read the original one-bottle thread through. It meanders, but there's a lot of good info in there, and I'm pretty sure that eventually there's a revised schem that has an output tx, a DI point, and some different (optimized) parts values. A lot of it is stuff that many folks on here could (and did) figure out themselves, but I was definitely happy to have it on paper in front of me.

Thank you for finding the link, that thing looks like piece of cake.. My hand will stay in my pocket. I have been warned of this before but like you said it never hurts to get a reminder.

Hm so re read the original.. I will do my best to get around to it. I barely have time to order parts and read all of the tube information you guys have sent me! I need to start absorbing this while I order and wait for parts.

 

[buildafriend]

Its asking for log or audio taper pot right? the whole old designators, new designators, and american vs euro designation information makes this really confusing. Why don't people just say Log or Lin? is it that hard?

 

[buildafriend]

I do not know how to source the power transformer for his original PSU

I know I need to use high voltage caps

I know I need primaries that are for 120V

I know the secondaries from the top winding to the 1st center tap need to put out 240V

and I know I need 6.3 volts coming out of the 2nd center tap to the bottom winding

But where do I find a toroid that meets these specs?

Do any of you have any nice examples of high end smoothing caps?

 

[buildafriend]

Do I need any kind of special 1N4007's? Are the ones rated at 1 Amp 1000 Volts good enough?

 

[gemini86]

All 1n4007 are 1000v 1a...

Hammond makes tube voltage transformers, as does antec. I also like the pts from ted weber. And a center tap is just that...a tap in the center of a winding. You just need 240V and 6.3(or 12.6). Center taps are optional.

 

[buildafriend]

What if I used http://angela.com/angelametalizedpolypropylenecapacitor18uf630vdc-2.aspx as my output coupling capacitor? ( 1.8uF instead of 2.2uF )

 

[abechap024]

What if I used http://angela.com/angelametalizedpolypropylenecapacitor18uf630vdc-2.aspx as my output coupling capacitor? ( 1.8uF instead of 2.2uF )

The smaller the cap you put in, the higher the lowest frequency AC signal it can pass. Depending on the circuit it may or may not start audibly rolling off the lows, or phase shifting low frequency content. I would stick with at least 2.2uf.

 

[buildafriend]

All 1n4007 are 1000v 1a...

Hammond makes tube voltage transformers, as does antec. I also like the pts from ted weber. And a center tap is just that...a tap in the center of a winding. You just need 240V and 6.3(or 12.6). Center taps are optional.

Okay I will have to look into all of those and weigh my options.

I got really ambitious about this whole thing and did half of my ordering. Without you guys and a some very sparse mentors, I could not do this. I decided to make four of these.

Sincerely, thank you.

Non polarized cap questions:

It seems like some of these parts are hard to find in the appropriate size. I could just order WIMA or Orange Drop caps from mouser but I want to use cooler high end parts. I was pointed in the direction of using the Angela website to source things but I can't find a matching brand set of coupling caps for high voltage. The input coupling cap seems to be easy to acquire, it's a 0.022uF . The 2.2uF on the output seems to be the rarity. I checked the SOZO site and they don't seem to have anything "boutique like" either. What is the 47pF cap doing? 47pF at 350V or more is something new to me. That is a super small capacitance and a pretty large voltage.

To recap: I want a nice matching set of boutique high voltage capacitors that are 0.022uF & 2.2uF for coupling, and one 47pF that is doing something that I don't understand. 

Polarlized cap selection questions:

Coming soon.