• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

E130L in Triode mode

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#41
E130L PP

I'm putting some parts together to build a E130L PP 50/60W p/c dual mono Power Amp, I have a couple of O/P trannys 2.6k 4-8ohm from Hungary, drivers will be 6N6P, I may use OA2,s on screen grid, any advice on B+ & filament Power Transformers plus Power Supply would be gratefully appreciated.
 
#42
A plate to plate load impedance of 2.6 kOhms maybe on the very high side for a pair of these tubes, as all datasheets by Philips and Siemens recommend 1.6 kOhms. You'll need 300 Vdc plate supply, so a stock 230/230 Vac, or even better 230/115-0-115 Vac isolation transformer plus a 12 or 24 Vdc SMPS most probably are the cheapest PSU »iron«.
Best regards!
 
#44
2.6k high side

Kay Pirinha said:
A plate to plate load impedance of 2.6 kOhms maybe on the very high side for a pair of these tubes, as all datasheets by Philips and Siemens recommend 1.6 kOhms. You'll need 300 Vdc plate supply, so a stock 230/230 Vac, or even better 230/115-0-115 Vac isolation transformer plus a 12 or 24 Vdc SMPS most probably are the cheapest PSU »iron«.
Best regards!
Click to expand...

I did take 2.5 from a schematic somewhere else on the web
 
#45
Kay Pirinha said:
A plate to plate load impedance of 2.6 kOhms maybe on the very high side for a pair of these tubes, as all datasheets by Philips and Siemens recommend 1.6 kOhms. You'll need 300 Vdc plate supply, so a stock 230/230 Vac, or even better 230/115-0-115 Vac isolation transformer plus a 12 or 24 Vdc SMPS most probably are the cheapest PSU »iron«.
Best regards!
Click to expand...

I think I'll get a price for 1.6k transformers then, my stupid mistake, there is someone in Hungary selling (so called) transformers for E130L 50w PPP, came across it when looking for parts, the only other people that have a 1.6 primary impedance transformer for 50w is Lundahl, I like their stuff but it ain't cheap.
 
#49
Now im left wondering what the voltage gain in a 6N6P long tailed pair would be approximately, i think somewhere around 22-24. that means your 9VAC RMS drive requirement would be met with ample reserve at less than .5VRMS in.



perhaps add some light feedback to the second triode to increase bass response?
 
#51
E130L PP Transformer.

Some of You out there might find this useful,

Those nice guys in Poland are making me some nice custom transformers for very reasonable cost for E130L.

Supply, 300V
Nom Anode, 250m/A
Nom Power, 60w
input imp, 1.6k
o/p imp, 4-8 ohms
Circuit type, PP
UL Tap, 43% (not used but no extra cost)
 
#52
E130L PP

Tubelab_com said:
I have always had a listening preference toward high voltage and higher than normal load impedance in SE amplifiers. This may be influenced by my speakers, and my preference toward large dynamic headroom. However the measurements do point to very good results at high load / voltage. Keep in mind that I was slightly over spec on the voltage. It worked great, but total operating time has been about 5 hours. The long term effects of operation at these voltage levels is unknown.

When you operate the tube at a higher voltage, more bias is required to control the current. This allows you to run more drive. If the tube likes it (remains linear) more power will result. In this case the plate will swing down to about 30 volts without distorting. Can't get there with a 6L6!

Careful measurements under various load, bias and supply voltage conditions has not been done yet. For now, I am trying to sort through a really large quantity of tubes to decide which ones to keep. I plan to crank through a dozen or more different potential output tubes this weekend. I will get back to these tubes later.

I bought a very large pair of Plitron P-P OPT's (400 watts, 1.2 K ohm) surplus last year. I have been looking for the right tubes to feed them. That section of the data sheet that shows 60 watts from a pair with a 1.6 K load keeps talking to me. 60 watts from a 300 volt supply with only 9 volts of drive, I'm thinking that a quad running from about 400 volts into 1.2K would just scream! Of course I could lower the supply, switch taps on the OPT, and run class A for about 30 watts too.
Click to expand...

Hi,
I know this is a post from 12 years ago, but I'm about to embark on a E130L project, Transformers are (custom)Toroid 1.6k impedance with o/p impedance being 4-8 ohms, they do have a UL taps, I have opened a thread on here (E130 PP), there are various various iterations of this on here, but You have actually done this, where did you end up with it?
 
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