• 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.

Oh no...not another Baby Huey EL84 build.

Prepping...
 

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It is up and running!

Yeah, congratulations! As Prasi said. Looks really good! I have enjoyed your thread here and the skill and inventiveness you have shared. And the resulting amp sounds great on your Youtube video. I have a few questions/requests, for my own education as well as future builders, and the Wiki’s completeness.

1. Could you kindly and for the record take an overall photo and some detailed ones of the underside, to show the wiring?

2. There is a small toggle switch between the PCBs on top; I assume this is for switch the bias measurements. The wires go out the back, where you plug in a self-made adapter to measure bias using a multimeter?

3. It would be very helpful to other builders if you could measure and record key operational voltages on the amp. In the BHEL34 thread gabo did some for his KT88 build, but I don’t recall that anyone did that for EL84 PCBs. I’m especially interested to know the actual operating conditions of the ECC83.

4. After some critical listening (hopefully you will have time soon) your assessment of the BHEL84 performance will be very welcome. Especially in comparison with the Broskie “Uncommonly good” 6N1P/EL84 amp you had previously built and enjoyed. What tubes are your using?

Thanks again for this enjoyable and informative thread.
 
1. Could you kindly and for the record take an overall photo and some detailed ones of the underside, to show the wiring?
Yes. There is some temporary board that I'm using since I'm planning a 21st century Maida regulator. So disregard that.

2. There is a small toggle switch between the PCBs on top; I assume this is for switch the bias measurements. The wires go out the back, where you plug in a self-made adapter to measure bias using a multimeter?
That is the on-off switch. And you are correct that I have a self-made adapter to measure bias with a multimeter. Picture soon.

3. It would be very helpful to other builders if you could measure and record key operational voltages on the amp. In the BHEL34 thread gabo did some for his KT88 build, but I don’t recall that anyone did that for EL84 PCBs. I’m especially interested to know the actual operating conditions of the ECC83.
I'll do that once the regulator has been installed because the temp board has too high a voltage and I can't be bothered to lower it.
4. After some critical listening (hopefully you will have time soon) your assessment of the BHEL84 performance will be very welcome. Especially in comparison with the Broskie “Uncommonly good” 6N1P/EL84 amp you had previously built and enjoyed. What tubes are your using?
Ofcourse. Did some early comparison between this BH...and my son's Broskie with 6p1p. No contest. BH is in a league above. But not a like for like comparison ofcourse. Because of different output transformers, tubes and coupling caps. I have already altered my Broskie el84 version to a podwatt type...that should tell you something already. Because the Broskie was fine for Mission 753 in my kids room. But just not good enough of my main speakers.
 
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Thingy to measure the output tube voltage across the measuring resistor. Can only measure one tube a time. Tighten the multimeter probe. Measure. Unscrew..put in other terminal ...tighten...measure. Quite cumbersome. But I did not want a digital voltmeter display somewhere.
 

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