Grateful Dead Music Forum

Unity gain is essentially the same output level as the pickups with no buffer. what goes in level wise is what comes out. with the stock TPC1 it is slightly less then unity or slightly less output level. what this accomplishes is that you can run your preamp a notch higher in level vs. unity output. in tube preamps this gives a slight increase in voltage to the preamp tubes and for some, and jerry, this was a desired effect. tone wise from the guitar standpoint there is no tone difference unity or slightly less. as i stated, it is just an output level.

Thanks Scarlet... my assumption about a 'slight gain' was wrong I asked him the same question, but his response wasn't as detailed.

I did detect a slight decrease in volume in the first Wald buffer I used... in all the othere I've installed (many of them), and use myself, the volume is very close to the same. That led me to believe that there was just some variance in the first buffer's components that caused the slight decrease... It's probably more an issue of the pups I used, which were single coils, home grown, with pretty low impedance. All the rest of the pups I've used with the buffer have been high impedance DiMarzios

milobender wrote:

Unity gain is essentially the same output level as the pickups with no buffer. what goes in level wise is what comes out. with the stock TPC1 it is slightly less then unity or slightly less output level. what this accomplishes is that you can run your preamp a notch higher in level vs. unity output. in tube preamps this gives a slight increase in voltage to the preamp tubes and for some, and jerry, this was a desired effect. tone wise from the guitar standpoint there is no tone difference unity or slightly less. as i stated, it is just an output level.

Thanks Scarlet... my assumption about a 'slight gain' was wrong I asked him the same question, but his response wasn't as detailed.

I did detect a slight decrease in volume in the first Wald buffer I used... in all the othere I've installed (many of them), and use myself, the volume is very close to the same. That led me to believe that there was just some variance in the first buffer's components that caused the slight decrease... It's probably more an issue of the pups I used, which were single coils, home grown, with pretty low impedance. All the rest of the pups I've used with the buffer have been high impedance DiMarzios

This is a great thread and it's great that we are all on the same page about this, now, and can have a good understanding of what we are using.
I've installed four. I never noticed any drop in volume, but I wasn't really trying to hear any either, so it has to be very small.
The whole explanation Mike Wald gave that is quoted above makes a whole lot of sense and is very clear.
Thanks for diggin that up, Scarlet

For those of you with onboard buffers, did you install them yourself and is it a relatively easy process? I'm not much of an electrician but it appears that for my Ibanez, I would basically splice the buffer in between the pickup selector and the jack, correct? (obviously a blaster involves a bit more...)

I would say, if you aren't using an OBEL and your guitar is a passive Ibanez, put it between the pup selector switch and the main volume... but you'll have to change the pot to a 25K. You could try it between your stock volume control and the output jack and see what it does... it may work fine that way... I've never tried it.

I have placed one between the pickup selector switch and the output jack with good results. It is an alternative if you are not installing OBEL and don't want to switch out your volume pots. This allows you to get the benefit of the buffer and still have multiple volume pots. Personally I prefer one volume and installing the OBEL, especially when using a signal sensitive pedal like an envelope filter. You'll need to find a place to house a 9 volt battery too.

Not hard to do- particularly if you have a wiring diagram to follow. Also be sure to wire the battery through the jack to disconnect it when you unplug or you'll eat up batteries. Might need to change to a TRS jack to do that? Or put a switch in.

Both mine are in the usual place- after pickups, after switch, before OBEL master 25k volume, or output.

Thanks to Mike Wald, there is this

I like the idea of one master volume but for this guitar there won't be an OBEL - although that might happen in a future guitar. As this is an initial foray I am hoping to keep it relatively low-impact in terms of wiring/re-wiring. Even though there is only two pickups/volume pots, at this point I am not sure I am comfortable with trying to add in a Master volume pot into the mix. How tricky is that while maintaining separate tone controls? Looking at the wiring diagram(s) I have it doesn't look that easy to remove the stock pots from the circuit(s) between the tri-sound selector switches and the tone pots/wires going to the pickup selector - its not a direct path per se - looks like signal goes through volume to tone and back to volume and out to the pickup selector?

The plus would be if I could manage that I could opt for a buffer with adjustable gain and use the other pot/hole for the gain adjustment. More research I guess.

Thanks Jim. Here is the schematics I am looking at:

I might have missed something, what guitar are you considering doing this to and what is the control configuration?

1982 Ibanez AR305 currently stock config

Yep, try putting the buffer between the pup selector switch and the output jack, (as per the AR 305 schematic above) but as has been mentioned above, replace the output jack with a stereo TRS type, wire the battery ground to the Ring lug of the jack, the Sleeve/Ground lug to your main ground bus, the Output of the Buffer to the Tip lug, and use a regular mono guitar cable... that will connect the battery when you plug in, and disconnect it when you remove the cable... just remember to remove the cable when you are done playing

flyingheelhook wrote:1982 Ibanez AR305 currently stock config

Oh, then yea, what he said.

milobender wrote:Yep, try putting the buffer between the pup selector switch and the output jack, (as per the AR 305 schematic above) but as has been mentioned above, replace the output jack with a stereo TRS type, wire the battery ground to the Ring lug of the jack, the Sleeve/Ground lug to your main ground bus, the Output of the Buffer to the Tip lug, and use a regular mono guitar cable... that will connect the battery when you plug in, and disconnect it when you remove the cable... just remember to remove the cable when you are done playing

Thanks guys!!!

replace the output jack with a stereo TRS type

(Hopefully) last question: do you recommend any particular jack/source?