I was wondering if anyone can assist in reading the drawings supplied with my transformers
https://www.edcorusa.com/Attachment/DownloadFile?downloadId=2437
In the suggested mounting holes section, what are those two larger holes for? The wires underneath?
https://www.edcorusa.com/Attachment/DownloadFile?downloadId=2437
In the suggested mounting holes section, what are those two larger holes for? The wires underneath?
Hi,
I am building a TSEII for use as 45 tube amp only and have a question regarding appropriate the power transformer to use... After spending many hours researching this forum and the Tubelab website I decided my safest bet as a newbie is to purchase an Edcore XPWR131 that many forum members have used with great success. When I communicated with the company that I am going to order the opt's from, it was mentioned he thought the Edcore XPWR001 was more appropriate for an amp that was intended for 45 tubes only.
I find little mention of the XPWR001 on this forum and I would appreciate other opinions of whether it would perform as well (has the correct ratings) for this purpose?
The $15 price difference is irrelevant.
Thanks...
I am building a TSEII for use as 45 tube amp only and have a question regarding appropriate the power transformer to use... After spending many hours researching this forum and the Tubelab website I decided my safest bet as a newbie is to purchase an Edcore XPWR131 that many forum members have used with great success. When I communicated with the company that I am going to order the opt's from, it was mentioned he thought the Edcore XPWR001 was more appropriate for an amp that was intended for 45 tubes only.
I find little mention of the XPWR001 on this forum and I would appreciate other opinions of whether it would perform as well (has the correct ratings) for this purpose?
The $15 price difference is irrelevant.
Thanks...
The XPWR001 does not seem appropriate for the TSE/TSE-II.
Quoting George from Tubelab.com
The XPWR001 seems quite underrated:
500V @ 100mA -- insufficient
5V @ 2A -- adequate but 3A gives a little headroom
6.3VCT @ 1A -- insufficient. Each 45 uses 1.5A so you need atleast 3A here.
I think I would choose something else as this one is a "universal" type for both 300B and 45.
Unless your OPT is also from Edcor and you want it all to match, for a 45 only I personally would go for a Hammond 370EX. Angela.com and a few other vendors have them in stock so there is also no wait time.
EDIT: one thing worth noting is that with the 370EX I had slightly higher B+ (around 320V), perhaps since my mains run a little high. Not extremely difficult to bring down, you can add a chassis mount resistor in the CLC section for that purpose.
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I also thought the Edcor XPWR001 was not sufficient for use as a PT in that instance, but the suggestion came from someone with much more knowledge then myself.
The Hammonds PT's concern me because some people have mentioned they have used and replaced them due to noise. I am not sure if that would be an issue with my Altec A7's, but it is a concern.
When I search the Edcor website, the XPWR028 seems a possibility for use as PT in a 45 only build;
Power transformer for a 120V, 60Hz. line to 6.3V at 2.5A, 5V at 3A and 3.5V at 5.5A.
But I am probably missing something because it does not seem that anyone has used it.
The XPWR131 seems more tried and proven...
The XPWR028 is not compatible. There is no high voltage tap, the 6.3V is underrated and the 3.5V tap is irrelevant.
I used a 370EX and replaced it due to noise but it was not in the sound or through the speakers, but rather a mechanical buzz from the transformer itself. I built a headphone amp that sits very close to my listening position so that buzz was annoying. For a speaker amp, assuming the listening position is a few feet away, I dont think it would be an issue.
FWIW I had also tried XPWR178 for a 300B TSE, and it buzzed atleast as much as the Hammond. Thus, after that experiment, is why I said that I would choose the 370EX.
As you mentioned the XPWR131 is proven and used by many, so that would be a safe bet either way.
I used a 370EX and replaced it due to noise but it was not in the sound or through the speakers, but rather a mechanical buzz from the transformer itself. I built a headphone amp that sits very close to my listening position so that buzz was annoying. For a speaker amp, assuming the listening position is a few feet away, I dont think it would be an issue.
FWIW I had also tried XPWR178 for a 300B TSE, and it buzzed atleast as much as the Hammond. Thus, after that experiment, is why I said that I would choose the 370EX.
As you mentioned the XPWR131 is proven and used by many, so that would be a safe bet either way.
Thanks for your fast and thorough replies to my inquiry... I have been impressed by your builds and appreciate you taking the time to explain your experience and reply to my questions.
I will use the Hammond or Edcor PT discussed.
My board has all components on the bottom side, with just the tube socket and potentiometers on the top. I'm mounting the board under plexiglass, with tube socket and potentiometer hole in the plexiglass. What I need to know is where would I add holes for multimeter grabbers to check for drivers and 300Bs, also B+ and B-. Are the directions in post 542, the best locations? I'm planning on soldering small loops of spare wire to the testing locations, so the grabbers will have something to hook onto. The board will hang a 1/2 inch below the plexiglass and the plexiglass 1/4 inch above the top plate. I figure this might give me some air flow around the board and plexiglass.
I've been designing my front panel using the front panel express software (thanks so much for the starting point itsikhefez!). For measurements, I placed the TSE-II PDF from the front of this thread on the front panel in the software, and then layed out the drill holes I wanted on top of it visually. I printed out a copy and it looks pretty good.
I wanted a sanity check on this method in case there's discrepancies in the PDF and the actual board, or the way graphics are displayed etc. . .So far, it seems more accurate then trying to measure with those electronic callipers.
I wanted a sanity check on this method in case there's discrepancies in the PDF and the actual board, or the way graphics are displayed etc. . .So far, it seems more accurate then trying to measure with those electronic callipers.
That's basically how I did the layout for the tube sockets, standoffs and bias adjustment holes. One sanity check I did was to use the Ruler tool in FPD and ensure the board image size was the same as the physical PCB, 8.5x5.5.
You're welcome, hope it helps!
