Tweet
My current amo has evolved quite a bit - kind of a 'living breadboard' of some sort. Started as a TTT inspired 6L6 fixed bias, with normal and overdrive channels, master volume and reverb. One of the first change was to go to cathode-biased 6V6 (like a 5e3 output stage). I can change from 6V6 to 6L6 by switching the transformer impedance setting (8Ohm for 6L6 - original configuration, and 4Ohm - with 8Ohm speaker - for 6V6)
After multiple changes, it has evolved in its the current configuration. The last (and maybe most significant) change has been the addition of a VVR. I got rid of the overdrive channel (which was picking some noise anyway, and the master volume. I like this a lot, as I can set the amp just right and control it from my guitar pickup settings (tele with 4 way switch), volume and tone. This is absolutely great, and I don't even use any pedals (except for the tuner pedal) anymore - I just like 'playing the amp' better.
So, in a way my current amp is pretty close to a Princeton reverb - less the vibrato - but I have a 'spare' 12AX7 that could be used for one - I will add it in my next build.
Now, I am planning on re-building the amp (as it really messy now after all the chamges, and more like an experimental 'breadboard' than a really well built amp). My plan is to rebuilt it, but in a very clean, reliable way, with a;;l the controls at right places, etc...)
An obvious way would be top start with a Princeton Reverb board and layout.
First question: use the standard Fender board/layout, or the Hoffman layout? Which is best (and why)?
The final amp will be pretty much like a Princeton reverb in overall structure, with the following mods:
1. Output stage with cathode bias and VVR
2. Possible higher B+ voltage (note that I have over sized trannies, so this is OK - I get a little more power if needed). I use a solid-state rectifier.
3. Higher voltage for the PI (since the preamp supply will be separated from the power stage due to the VVR, I can put where I want)
4. Of course, 470 Ohm screen resistors
5. A Mid pot in place of the fixed resistor in the tone stack.
6. Log pot for the reverb recovery for better control
7. Switchable feedback resistor to run open loop like a 5E3
Other possible mods:
1. Add a dwell control for the reverb opinion please?
2. Add a bright switch on the volume pot?
I would love to hear from those who built Princeton reverb (and variants) and their experiences. I am taking my time with this one, as I want to do a much more 'professional' built.
After multiple changes, it has evolved in its the current configuration. The last (and maybe most significant) change has been the addition of a VVR. I got rid of the overdrive channel (which was picking some noise anyway, and the master volume. I like this a lot, as I can set the amp just right and control it from my guitar pickup settings (tele with 4 way switch), volume and tone. This is absolutely great, and I don't even use any pedals (except for the tuner pedal) anymore - I just like 'playing the amp' better.
So, in a way my current amp is pretty close to a Princeton reverb - less the vibrato - but I have a 'spare' 12AX7 that could be used for one - I will add it in my next build.
Now, I am planning on re-building the amp (as it really messy now after all the chamges, and more like an experimental 'breadboard' than a really well built amp). My plan is to rebuilt it, but in a very clean, reliable way, with a;;l the controls at right places, etc...)
An obvious way would be top start with a Princeton Reverb board and layout.
First question: use the standard Fender board/layout, or the Hoffman layout? Which is best (and why)?
The final amp will be pretty much like a Princeton reverb in overall structure, with the following mods:
1. Output stage with cathode bias and VVR
2. Possible higher B+ voltage (note that I have over sized trannies, so this is OK - I get a little more power if needed). I use a solid-state rectifier.
3. Higher voltage for the PI (since the preamp supply will be separated from the power stage due to the VVR, I can put where I want)
4. Of course, 470 Ohm screen resistors
5. A Mid pot in place of the fixed resistor in the tone stack.
6. Log pot for the reverb recovery for better control
7. Switchable feedback resistor to run open loop like a 5E3
Other possible mods:
1. Add a dwell control for the reverb opinion please?
2. Add a bright switch on the volume pot?
I would love to hear from those who built Princeton reverb (and variants) and their experiences. I am taking my time with this one, as I want to do a much more 'professional' built.
Comment