Re: Apex Jr TA110-W transformer
Steve,
Thanks. The price surely is right. I was planning on ignoring the 48V taps and use the 40V. Have you tried putting any load on them? Connect a 100W lamp maybe and see how they might perform. I might consider using 4 as well if I have enough space in the cabinet.
Regards,
Dinesh
Thanks, ZM. PM sent to AR2Zen Mod said:why not - if you use two of them , to have twice 40Vac
you can always ask AR2 which one from Apex he use [/B]
zettelsm said:I am going to use the MM TA110-Ws for my Pumpkin-Shunty AC power supply. Doing a quick hookup to check voltage, two MM TA110-Ws can be hooked up to supply a nominal 40V - 0 - 40V or 48V - 0 - 48V, the latter too much probably for all but the lowest of line voltages -- Japan perhaps @ 100VAC line.
The transformers appear to be good quality E-I core and should have no problem supplying the required current to a stereo pair of preamp-regulators. In typical DIY overkill fashion, I picked up 4 of the TA110-Ws so I can go dual-mono. 😎
The price is certainly very right!
Steve Z [/B]
Steve,
Thanks. The price surely is right. I was planning on ignoring the 48V taps and use the 40V. Have you tried putting any load on them? Connect a 100W lamp maybe and see how they might perform. I might consider using 4 as well if I have enough space in the cabinet.
Regards,
Dinesh
Re: Re: Apex Jr TA110-W transformer
Hi Dinesh,
I have not checked out the load regulation of the trafos yet, but maybe tomorrow night a work I might have time to do so. Looking at the physical size and with my plan to use two per channel, I figured they would be well within their current capabilities and voltage droop loaded would not be a problem.
I plan on having the transformers and rectifiers in a separate box and bring only DC up to the preamp enclosure.
Steve Z
dviswa said:
Thanks, ZM. PM sent to AR2
Steve,
Thanks. The price surely is right. I was planning on ignoring the 48V taps and use the 40V. Have you tried putting any load on them? Connect a 100W lamp maybe and see how they might perform. I might consider using 4 as well if I have enough space in the cabinet.
Regards,
Dinesh
Hi Dinesh,
I have not checked out the load regulation of the trafos yet, but maybe tomorrow night a work I might have time to do so. Looking at the physical size and with my plan to use two per channel, I figured they would be well within their current capabilities and voltage droop loaded would not be a problem.
I plan on having the transformers and rectifiers in a separate box and bring only DC up to the preamp enclosure.
Steve Z
Re: Re: Re: Apex Jr TA110-W transformer
Wow, 2 Box design huh? Worried about interference or simply no space in the cabinet? The rectifiers are on the Shunty board, just curios, what would you gain, by building a rectifier in the other box?
Please do.zettelsm said:I have not checked out the load regulation of the trafos yet, but maybe tomorrow night a work I might have time to do so.
zettelsm said:I plan on having the transformers and rectifiers in a separate box and bring only DC up to the preamp enclosure.
Wow, 2 Box design huh? Worried about interference or simply no space in the cabinet? The rectifiers are on the Shunty board, just curios, what would you gain, by building a rectifier in the other box?
Re: Apex Jr TA110-W transformer
I hope to gain additional complexity, expense, ungainliness, and a large measure of overkill. You know, the standard DIY virtues.
😀
Seriously, the two box design will give me more space to play with in each box without being cramped, hopefully avoids some potential problems with noise and hum induced into low level circuits by AC and magnetic fields of the transformers, likewise avoid recifier diode noise. And I happen to have a utility box on hand that will be very serviceable for the power supply and can be hidden away on the floor by the BPT balanced power supply.
I figure a plain 2U or 3U rack mount chassis and enclosure for the preamp can be dressed up with a wood faceplate to match the planned enclosures for the two F4 amps being built now, too.
Steve Z
dviswa said:
Wow, 2 Box design huh? Worried about interference or simply no space in the cabinet? The rectifiers are on the Shunty board, just curios, what would you gain, by building a rectifier in the other box?
I hope to gain additional complexity, expense, ungainliness, and a large measure of overkill. You know, the standard DIY virtues.
😀
Seriously, the two box design will give me more space to play with in each box without being cramped, hopefully avoids some potential problems with noise and hum induced into low level circuits by AC and magnetic fields of the transformers, likewise avoid recifier diode noise. And I happen to have a utility box on hand that will be very serviceable for the power supply and can be hidden away on the floor by the BPT balanced power supply.
I figure a plain 2U or 3U rack mount chassis and enclosure for the preamp can be dressed up with a wood faceplate to match the planned enclosures for the two F4 amps being built now, too.
Steve Z
Re: Pumpkin volume control
Hi Steve. I had the Elma's lying around, and since I am building the Pumpkin into this other wooden box I decided to use hem. I didnt really feel like taking the twisted setup apart😉 It took a long time to put it together, anyway. The main effect soundwise is the scratching noise with the Elma's😀. The Twisted attenuator is much better, and I will probably be using the Joshua/Darwin, with a pair of Shunty supplies and the UGS modules that will show up shortly 😉
🙂
zettelsm said:
So Mr. Steen, do I see potentiometers in place of the Twisted Pear stepped volume control and input-output boards?
Would you care to elaborate on the changes and effects on sound, if any? I would like to benefit from your experience and reasons for the changes. . .
Thanks!
Steve Z
Hi Steve. I had the Elma's lying around, and since I am building the Pumpkin into this other wooden box I decided to use hem. I didnt really feel like taking the twisted setup apart😉 It took a long time to put it together, anyway. The main effect soundwise is the scratching noise with the Elma's😀. The Twisted attenuator is much better, and I will probably be using the Joshua/Darwin, with a pair of Shunty supplies and the UGS modules that will show up shortly 😉
🙂
Re: Re: Pumpkin volume control
Thank you very much for your reply -- I am relieved. I saw the slick Joshua/Darwin implementation you used and ordered enough stuff for a balanced set-up . . . imitation being the most sincere form of flattery. Well, other than money.
Pardon another question -- what are UGS modules? A URL is fine.
Thanks for your time.
Steve Z
steenoe said:
Hi Steve. I had the Elma's lying around, and since I am building the Pumpkin into this other wooden box I decided to use hem. I didnt really feel like taking the twisted setup apart😉 It took a long time to put it together, anyway. The main effect soundwise is the scratching noise with the Elma's😀. The Twisted attenuator is much better, and I will probably be using the Joshua/Darwin, with a pair of Shunty supplies and the UGS modules that will show up shortly 😉
🙂
Thank you very much for your reply -- I am relieved. I saw the slick Joshua/Darwin implementation you used and ordered enough stuff for a balanced set-up . . . imitation being the most sincere form of flattery. Well, other than money.
Pardon another question -- what are UGS modules? A URL is fine.
Thanks for your time.
Steve Z
Steve,
Just stick with the Joshua/Darwin, its a very good choice. Dont ever worry about me changing stuff, I do that all the time
Here is the UGS:http://www.diyaudio.com/forums/showthread.php?s=&threadid=116621
There is a link to the original thread in one of the first posts.
🙂
Just stick with the Joshua/Darwin, its a very good choice. Dont ever worry about me changing stuff, I do that all the time

Here is the UGS:http://www.diyaudio.com/forums/showthread.php?s=&threadid=116621
There is a link to the original thread in one of the first posts.
🙂
Magura said:
How warm does it become after a couple of hours?
Magura 🙂
Magura - Temperature measured on Shunty Heatsink (midle of it in between the fins) after 2 hours is 50 Degree Celsius. At the same time Pumpkin Heatsink is 53 Degree Celsius.
Too much ?

spavleski said:
Magura - Temperature measured on Shunty Heatsink (midle of it in between the fins) after 2 hours is 50 Degree Celsius. At the same time Pumpkin Heatsink is 53 Degree Celsius.
Too much ?
![]()

crazy danske metal boy will tell ya that's too cool ........... knowing his habits of burning mosfets as popcorns in oil bucket ............
hehehe
btw - temp is exactly as prescribed 😉
Zen Mod said:
crazy danske metal boy will tell ya that's too cool ........... knowing his habits of burning mosfets as popcorns in oil bucket ............
hehehe
btw - temp is exactly as prescribed 😉
Yeah, it's time to fine tune the bias, how about double for starters? 😀
Maguar 🙂
spavleski said:
Magura - Temperature measured on Shunty Heatsink (midle of it in between the fins) after 2 hours is 50 Degree Celsius. At the same time Pumpkin Heatsink is 53 Degree Celsius.
Too much ?
![]()
That's a lot cooler than I expected.....sounds reasonable (if you don't dare to bias itI) 😀
Magura 🙂
due to last several posts , and general attitude of members to my postings here , I decided to leave DiyA ......
as my farewell , I decided to make a present to first one who reply to this post ....... I'll send him bare (sans box) drivers - my RCA LC1B , and two ancient Goodmans compression drivers , as tweet helpers ;
if that ( someone ) is willing , I'll include few VQ caps ;
btw - I'll not pay for shipping .
as my farewell , I decided to make a present to first one who reply to this post ....... I'll send him bare (sans box) drivers - my RCA LC1B , and two ancient Goodmans compression drivers , as tweet helpers ;
if that ( someone ) is willing , I'll include few VQ caps ;
btw - I'll not pay for shipping .
spavleski said:🙂 April the 1st.![]()
hehe
I can bet that you bite at least for a second ........

Manu said:Must be 1st of April in Serbia today....
ZM is hunting the gowksky
Manu
hehe
what's "gowksky" ?

Zen Mod said:as my farewell , I decided to make a present to first one who reply to this post .......
I 'am the one who answered first ... correctly

Zen Mod said:
what's "gawksky" ?
It s a sort of cuckoosky
manu
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