Where is the first pre-amp tube located in the Deluxe? Is it the one closest to the power tubes or the one all the way against the wall? Also, is there a sight I can go to that tells me this info?
Where is the first pre-amp tube located in the Deluxe? Is it the one closest to the power tubes or the one all the way against the wall? Also, is there a sight I can go to that tells me this info?
the tubes in the HRDx are, from right to left:
1st preamp, 2nd preamp, phase inverter, 1st power tube, 2nd power tube. So the 1st preamp tube is the one on the right, not the one beneath the power tubes.
Last edited by Homer; 10-17-2002 at 06:06 AM.
"If you wind up with a boring, miserable life because you listened to your mom, your dad, your teacher, your priest, or some guy on TV telling you how to do your shit, then YOU DESERVE IT."
- Frank Zappa -
Thank you so much. Is the phase inverter the same thing as a reverb driver?
Last edited by waylon; 10-17-2002 at 06:12 AM.
no. The reverb in the HRDx is not tube driven. The power amp works as a "push-pull" power amp (whatever that means anyway ...), and the signal phase has to be shifted 180° for the pull side. The PI tube does that, and feeds the pull side with the inverted, the push side of the power amp with the non-inverted signal.
"If you wind up with a boring, miserable life because you listened to your mom, your dad, your teacher, your priest, or some guy on TV telling you how to do your shit, then YOU DESERVE IT."
- Frank Zappa -
Thanks Homer for sharing your knowledge. Just one more question-I have three different preamp tubes (2) Sovtek 12ax7, (1) Electro-Harmonix 5751, and also (1) NOS Jan GE 12ax7. If I understood correctly the NOs Jan GE should go in the far right slot for the "Fender sound", but then which remaining two should I use? I bought the 5751 for a reverb driver but did not understand that this amp did not have that. Should I just use the Sovteks to fill the remaining positions or what?
Thanks for all your help. I am trying to get the most out of this amp. I have already changed speakers and power tubes and rebiased them to 69 ma.
phew tough question, I'm not so much a tube expert. But I'll try (not sure if I'm right though, but this is the way I understand it).
The GE and EH tubes are both lower gain tubes than the sovteks, with the GE having even less gain than the EH. if you put a lower gain tube in V1 (1st preamp stage), you'll get more clean headroom (because the tube has less gain), resulting in the amp breaking up later and the overall sound having less preamp distortion.
Putting a low gain tube in the V3 slot (PI) has a similar effect I think, the signal going to the power amp will be less hot and the poweramp will clip later as well as possibly souding less "muddy".
If you have to swap the V3 tube depends on the tubes that are stock in the amp, how old they are and how much you play. In my experience (I play a Blues Deluxe) the PI tube goes bad first, so if you play alot, it might be good to replace it as well.
So, my take would be to try the GE in V1 and the EH in V3 and see how it sounds; but try different combinations and let your ears decide, but try to take a break now and then so your ears don't get tired :).
As I said, that's how I understand it; you can't break anything, cause all those tubes are variations of the ECC83/12AX7 tube, just with different gain / characteristics. Try them and let your ears decide if you like it.
"If you wind up with a boring, miserable life because you listened to your mom, your dad, your teacher, your priest, or some guy on TV telling you how to do your shit, then YOU DESERVE IT."
- Frank Zappa -
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