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DIY Stingray 3EQ Preamp
- Thread starter Dominic D
- Start date
Sorry, but I don't agree with you cause for tone circuits normally we use log. pots. This because of the human hearing and it's responce that's normally in log. scale.
The note saying that it could change the centre point for cut and boost does make sence to me. But also here should the responce on certain 'parts' of the pots turn will be more or less responsive.
For this type of active circuit, the tone pots really have to be linear. Anything from 25k to 250K will be fine as long as all three are linear and the same value. (The original has 50K pots.)
FWIW, this tone circuit topology itself dates back to the eighties as far as I'm aware. Probably from the hi-fi era. There are many many onboard preamps that use this circuit, tweaked in all sorts of combinations as a 3-band filter. The mid range control is, if I'm honest, fairly unimpressive. More a mid voicing I guess since it has such a low Q and only 6-7dB of cut and boost. (The treble has around +/-18dB!) But I guess still more useful and certainly less interactive than the mid range control from a fender tone stack...
It's a great project though for anyone who's interested in audio electronics. I'd recommend checking out stripboard as a way to make one-offs. It's a good way to start learning about board design I think. Plus it's cheap easy to find, and easier to solder than simple perf board and hookup wire. You just need a dremel or something to cut the tracks.
I'd also recommend learning to use one of the free spice programmes going around. This way you can check that a hand-drawn schematic from the web is going to work ok at the get-go...
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I would agree with you for a passive tone circuit but for an active one like this then linear pots are the way to go otherwise all the action happens at one end of the travel.
Could you tell me how much cost all parts and show me how u wiring this with pickups? thanks
The price depends on what you order and where you order them. For the basic setup (4 separate pots, no stacked pots) it costs about $16 + shipping at Mouser. There's a wiring diagram on the first post of this thread. The output of the pickups go to the hole marked "IN". For example, the output of a pickup selector switch or a blend would be wired to "IN" on the board.
Passive baxandall bass and treble EQ uses audio/log taper for the EQ controls. The two band MM preamp uses an audio taper and a reverse audio taper control for the EQ. Most active EQ's use linear for the EQ controls.
Some Sadowsky preamps used audio controls as they are modified Fender tone stacks. I'm sure there are other preamp circuits that use audio taper but the ones I mentioned are more exceptions than rules.
Some Sadowsky preamps used audio controls as they are modified Fender tone stacks. I'm sure there are other preamp circuits that use audio taper but the ones I mentioned are more exceptions than rules.
with what type of pickups can i use this preamp? active pickups or passive pickups ? or both ?
I want to use this preamp for a bass that I'm making.
There will be a PB pickup going into a volume pot and a tone section in parallel (the "roots" section). I'd like to add after that section a switch on (preamp section) / off (without).
The only thing I'm worried about is : with the position on, will the general volume be louder than (or, at least, as loud as) the position off ?
In position on (with your three band eq), there's the preamp volume so I can have the same output level on and off if the position on is louder on maximum level setting. Whether the position on has a weaker volume, no correction will be possible because the "roots section" volume is the general volume that lowers both the roots section and the preamp section.
I hope that my question is enough clear :-DDD
There will be a PB pickup going into a volume pot and a tone section in parallel (the "roots" section). I'd like to add after that section a switch on (preamp section) / off (without).
The only thing I'm worried about is : with the position on, will the general volume be louder than (or, at least, as loud as) the position off ?
In position on (with your three band eq), there's the preamp volume so I can have the same output level on and off if the position on is louder on maximum level setting. Whether the position on has a weaker volume, no correction will be possible because the "roots section" volume is the general volume that lowers both the roots section and the preamp section.
I hope that my question is enough clear :-DDD
Pretty sure it was designed for passive pickups, so I would stick with those.
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Hello people, I might have skipped past this, but is there anyone who can sell this preamp to me? Also with a blend pot? 
Thanks in advance.
Thanks in advance.
Would there be a way to use a passive vol and tone before this pre and use the passive vol as the master vol? Even if it means some type of short over the vol pot wires?
Just thinking of this pre for my jaguar, but i could probably use a dual stack pot for vol and mids........ Hmmmm
Just thinking of this pre for my jaguar, but i could probably use a dual stack pot for vol and mids........ Hmmmm
Don't know why, but in my case I had to change the output cap (C1) from 10uF to 33uF, otherwise preamp was quiet as hell. With 33uF cap everything is great. Also changed C8 from 2.2nF to 1nF to add more zinginess and clarity to highs.
