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by **TomMcNally** » Sat Apr 12, 2008 7:47 pm

Do you have a link to the Transcendars ? I don't see 'em on eBay.

The $ 20 Edcor XSE15-8-5K's sound really good.

by **kheper** » Sat Apr 12, 2008 8:14 pm

TomMcNally wrote:Do you have a link to the Transcendars ? I don't see 'em on eBay.

The $ 20 Edcor XSE15-8-5K's sound really good.

The only seller of Transcendars is:

http://myworld.ebay.com/ggaet

A 3k SE 8ohm 10W pair of outputs (not the 'economy' model):

http://cgi.ebay.com/Pair-3k-Audio-Outpu ... dZViewItem

by **TomMcNally** » Sun Apr 13, 2008 12:29 pm

More tubes from the box ! I found a set of Raytheon branded Mullard 6L6GC's (used) ... they sound great too.

by **EWBrown** » Mon Apr 14, 2008 8:23 am

The nice thing about this kind of amp design, and the "EL43 SE #3" that I built a few years ago, is that almost any pin-compatible power tube will work and sound quite nice in it.

IIRC, if pins 1 & 8 are tied together, it makes it even more "compatible" for those few power tubes with G3 connected to pin 1, rather than direct to the cathode.

/ed B in NH

by **TomMcNally** » Mon Apr 14, 2008 8:35 am

Right you are Ed ... Joe Esmilla's design has pins 1 and 8 on the output tubes connected, I didn't look into why - but obviously it works well.

by **EWBrown** » Mon Apr 14, 2008 9:23 am

I did the same thing to my upgraded ST70s, just makes them more "universal".

Didn't get much tube-ology done over the 3 day weekend
(I blew off Friday). Too much "outdoor" work friday and saturday, and too darn tired (as in totally pooped out) Sunday... Yellow_Light_Colorz_PDT_09

/ed B

by **funkmeblue** » Tue May 20, 2008 3:37 pm

hi, Ive lurking here for a few months. I've built a few guitar amps but this JE labs circuit is my first attempt at a hifi. I'm going with the edcor outputs and wish to use the ultra linear taps. Do I just remove the 100 ohm resistor tying pins 3 and 4 together and connect the ultra linear taps to pin 4? thanks for your time

by **kheper** » Tue May 20, 2008 4:19 pm

funkmeblue wrote:hi, Ive lurking here for a few months. I've built a few guitar amps but this JE labs circuit is my first attempt at a hifi. I'm going with the edcor outputs and wish to use the ultra linear taps. Do I just remove the 100 ohm resistor tying pins 3 and 4 together and connect the ultra linear taps to pin 4? thanks for your time

Yes. You may connect the screen (UL) tap of the transformer, directly to the screen, g2.

You can also place a switch between the screen tap and the plate tap/resistor, for the ability to change from triode to UL operation, as is shown below:
http://diyaudioprojects.com/Tubes/KT88/index.htm

There are other options:

You can connect the screen tap thru a resistor to the screen.

You can also connect the screen tap thru a resistor and a diode, in series, with the band of the diode pointing to towards the screen, to the screen.

The third option will give you the best fidelity, due the diode preventing AC back-flow.

http://www.webace.com.au/~electron/tubes/ul.html

'The technique of using a silicon rectifier diode on each Screen Grid in series with the Grid-stopper resistor []'

'AC signal output voltage from the Screen-Grids is prevented from conducting through to the output transformer, which means that the ultra-linear output stage operates as a negative feedback system only - ie Plate voltage is fed back to the Screen Grids via the transformer taps but not the other way around. '

http://www.webace.com.au/~electron/tubes/oes.html

by **funkmeblue** » Tue May 20, 2008 4:36 pm

great info, thanks....I'll have to look into the diode resistor circuit. I still want to be able to use other tubes besides el34's.

by **hasafraker** » Wed May 21, 2008 12:38 pm

http://www.transcendar.com/

They don't have product/prices listed on their site but they do have a email address for sales inquiries.

by **hasafraker** » Fri May 23, 2008 7:36 am

I sent an email to their sales address and they just got back to me, they ONLY sell on ebay, they do not have a catalog or price list. Too bad. Only took a couple days to get back to me, they can/will do custom jobs too.

by **kheper** » Fri May 23, 2008 7:50 am

hasafraker wrote:I sent an email to their sales address and they just got back to me, they ONLY sell on ebay, they do not have a catalog or price list. Too bad. Only took a couple days to get back to me, they can/will do custom jobs too.

http://myworld.ebay.com/ggaet is the only seller of TRANSCENDAR transformers on e-bay, which I have seen.

There have been no PP UL output transformers offered by this seller in a long time.

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