Tube Amp Archive

With the 15V rms, you'll have ~21v dc before the regulator, so it will have to dissipate 9 Volts times the total relay current, in your case about 120 ma?(my relays are ~40 ma each) which is over a watt, even with a good heat sink, that might get pretty darn hot. You might think about adding a serie...

My take is that you have two 1MA Masters. The NonHRM feeds a 150K and a 100Ktrim to ground with the wiper feeding the 1M OD master (or I think Dogears mentioned two 50K resistors in series acting like the mid point of the 100K trim) Feeding into the 1M OD master. This preserves the impedance that th...

Yup, with the 150K feeding the OD Master.

Hi Tommy,
The 1M is used if you are doing the HRM post OD tone stack with seperate masters for clean and od, Look at the 1997 skyliner schematic in the files section.
sgp

My bad, I can now see the bottom edge bends away.
I think the "Glaswerks special: compliment is cool, Gary sets the bar pretty darn High.

Hi Keith, I certainly won't argue with the Normster, But, It appears to me that a lot of your tube connections (the plate resistors and PI input resistors) are on the opposite side of the pcb, the side furthest from the tubes. those are tube holes on the top right? Please correct me if I'm looking a...

Just to clarify, I'm trying to switch between a hyb-a and the s3988009.2 circuits. and Now I see the 1997 specimen, which uses HRM, No pre-od network, but lacks the PAB. Isn't the PAB a good thing with the HRM? Now I'm spinning. I'm thinking that a good way might be the Hyb-A with a relay to switch ...

Thanks Gary, that's what it looked like to me. I know you have switched the HRM in and out, Do you have any tips/pointers as to what gets switched and what may not need to be. I don't want to compromise either circuit, but the idea of switching a daughter board in and out (like yours) sounds like wh...

Is the Rock/Jazz switch shown in the Rock position on the schematic? Do most of you agree that the jazz position is not very useful? Also, If I use the switch to change from HRM/non-HRM, I'll need to switch out the HRM, the pre-OD network and other components throughout the circuit? seems like this ...

Thanks will do!

Are there any recommendations?
thanks
sgp

Dogears, I'm still in the layout and ordering parts stages, but I was going to leave space on the board to be able to try both of those networks. Would I just use the values from the skyline schematic, with the hybrid-a topology? your post makes it sound like there is a better starting point, thanks...

I think it's showing a 50v tap for that purpose, If you don't have that tap you can use the Higher voltage tap with a bigger series resistor to drop the volts down.

This is mo better.
Thanks for catching that.

Your correct, I did NOT take the following stage input impedance into account. I was actually messing with a fender 5e7 (can I say that on this board?) which has the 1 meg volume pot as the next stage.