Hi there,
I've modified a UL Pro Reverb by giving the Normal channel a brownface bandmaster tone stack and a tone stack lift. The Vib channel is basically stock.
Both channels feed the reverb, and I'm happy with both. However, Id like to be able to tamp down the output level of the "brown" channel so I can run it with more gain while still running the more stock vibrato channel cleaner.
Coming out of the second gain stage of each channel, I have a .022 coupling cap to a 220k resistor, the two 220ks meet at the junction before the reverb.
I was thinking about using a pot as a variable voltage divider where the coupling cap meets the Normal's 220k; seems to work but also tames the Normal channel's tone. Any ideas?
Thanks!
Master on one channel Fender Mod
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pompeiisneaks
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Re: Master on one channel Fender Mod
I think you'd still need some resistance on each side to avoid the reason the resistors are there, the mixing resistors keep the signal from back feeding as I understood it (but someone correct me if I'm wrong). Basically 220 to 440k are common mixing resistors, I'd figure say a 250k pot with a 220k mixing resistor on either side may work. That way you still keep the minimum mixing resistor there and have the ability to balance as you say. (or maybe go for 100k minimum with a 250k pot? You could try a few values to get it right.)
Although, now that I think about it, you'd have near 0 resistance on one side but have higher resistance on the other, so that would work. Maybe a 500k would do fine, so that if you have it near 0 on one half, you'd have 500k on the other to resist any of the issues caused without mixer resistors? Not sure. I guess play with the idea and see what you get
~Phil
Although, now that I think about it, you'd have near 0 resistance on one side but have higher resistance on the other, so that would work. Maybe a 500k would do fine, so that if you have it near 0 on one half, you'd have 500k on the other to resist any of the issues caused without mixer resistors? Not sure. I guess play with the idea and see what you get
~Phil
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Re: Master on one channel Fender Mod
Any attenuation before the PI is going to kill the drive available for the channel you use it on..
The best way to do this thing is to cascade the normal into the vib side at the inputs of the vib channel.
That 220k junction before the reverb.. is that stock? hold on let me pour a coffee..
So,
1. Rwmove the tail of the coupler for the normal channel from the 3' wire that connects it to that mixer before the reverb. (the 220k mixer) Ground that wire right there at the closest ground point near the normal's input.
2. We need a new pot (probably in low input hole on normal channel) 500k is fine. Tail of that coupler now terminates input of that pot.
3. Shielded wire grounds to back of that pot.
4. Signal of shielded wire terminates onto the same input grid pin of the vib channel where vib channel's input is terminated.
Now you have to tweak values on the normal channel for when the cascade is being used.
Hmm.. it's not going to be an ideal setup, still. For an ideal setup you need to add a somewhat more complex switching system that jumps across a master volume later in the circuit, and that is still going to give you grief about gain settings vs volume...
Idea two: Disconnect the normal channel's volume control. Do everything described above except use that voulume as the tail of that channel. The coupler we tailed out to a new volume goes to the inout of that pot now, and the shielded situation comes from that pot to the input grid of the other channel as described above.
The problem of gain over volume still exists in this setup, but the normal channel input is unattenuated into it's second stage; it's a distortion unit.
Meh
Idea three: Give up the idea that it's a two channel amp. brb
The best way to do this thing is to cascade the normal into the vib side at the inputs of the vib channel.
That 220k junction before the reverb.. is that stock? hold on let me pour a coffee..
So,
1. Rwmove the tail of the coupler for the normal channel from the 3' wire that connects it to that mixer before the reverb. (the 220k mixer) Ground that wire right there at the closest ground point near the normal's input.
2. We need a new pot (probably in low input hole on normal channel) 500k is fine. Tail of that coupler now terminates input of that pot.
3. Shielded wire grounds to back of that pot.
4. Signal of shielded wire terminates onto the same input grid pin of the vib channel where vib channel's input is terminated.
Now you have to tweak values on the normal channel for when the cascade is being used.
Hmm.. it's not going to be an ideal setup, still. For an ideal setup you need to add a somewhat more complex switching system that jumps across a master volume later in the circuit, and that is still going to give you grief about gain settings vs volume...
Idea two: Disconnect the normal channel's volume control. Do everything described above except use that voulume as the tail of that channel. The coupler we tailed out to a new volume goes to the inout of that pot now, and the shielded situation comes from that pot to the input grid of the other channel as described above.
The problem of gain over volume still exists in this setup, but the normal channel input is unattenuated into it's second stage; it's a distortion unit.
Meh
Idea three: Give up the idea that it's a two channel amp. brb
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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Reeltarded
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Re: Master on one channel Fender Mod
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.