John East UNI 4 knob preamp question

[JC BASS 91]

Question for those that have this preamp in your bass, WHAT bass is it in? A custom build or did you add it to an existing bass? Replace a factory preamp perhaps?

The preamp is a push/pull active/passive on the passive tone control, stacked volume/blend, stacked bass/treble( with a push/pull bright switch), and a stacked mid/mid-sweep.

The reason I ask is because I made a foolish mistake and bought this preamp (about two years ago) to replace an existing preamp in a bass I have. I thought it would fit, but it absolutely will NOT fit in my 2005 Fender Deluxe Active Jazz V. I should have researched more before I made my purchase, which is VERY unusual for me.

Now I am in a position where I have this preamp and don’t have a bass to put it in. I have considered building a Warmoth bass to use it, and I have also considered selling it. However, I would rather use it in something. So, if you have it in your bass, do you have pics of it installed in the cavity? I’m trying to gauge where I go from here…

Thank you!

 

[Funkinthetrunk]

My favorite preamp. I have it in several basses, as in my MTD 535. Not really for JB plate installation.

 

[XLunacy]

Custom build, made to fit the preamp so lots of extra room.

East offers preamps designed for the tiny J bass cavity (J-Tone, J-Retro), but maybe you could try a similar layout :

 

[Funkinthetrunk]

I have the J Tone also. But some players insist on having mids, which these don't.

 

[JC BASS 91]

I ended up deciding to leave the stock preamp in the Fender as my main drive to change it out was to have the active/passive option.

 

[JC BASS 91]

My favorite preamp. I have it in several basses, as in my MTD 535. Not really for JB plate installation.
View attachment 5145013

This image is SUPER helpful!! Thank you for posting it!

 

[mcnach]

Question for those that have this preamp in your bass, WHAT bass is it in? A custom build or did you add it to an existing bass? Replace a factory preamp perhaps?

The preamp is a push/pull active/passive on the passive tone control, stacked volume/blend, stacked bass/treble( with a push/pull bright switch), and a stacked mid/mid-sweep.

The reason I ask is because I made a foolish mistake and bought this preamp (about two years ago) to replace an existing preamp in a bass I have. I thought it would fit, but it absolutely will NOT fit in my 2005 Fender Deluxe Active Jazz V. I should have researched more before I made my purchase, which is VERY unusual for me.

Now I am in a position where I have this preamp and don’t have a bass to put it in. I have considered building a Warmoth bass to use it, and I have also considered selling it. However, I would rather use it in something. So, if you have it in your bass, do you have pics of it installed in the cavity? I’m trying to gauge where I go from here…

Thank you!

View attachment 5144892 View attachment 5144893

I bought one for my Sandberg VM4... and I could *almost* fit it in, but not quite... so it's still in the box waiting for an opportunity, some day.

 

[JC BASS 91]

I bought one for my Sandberg VM4... and I could *almost* fit it in, but not quite... so it's still in the box waiting for an opportunity, some day.

That's kind of where I am with mine. It has been sitting in the box on the shelf for almost two years waiting for said opportunity.

 

[logdrum]

It will not fit a J route even a deluxe J route (side input jack). You need to route a battery box and might as well make it 18V. The one he makes for the Jazz plates 2 have a shorter - narrower circuit boards

 

[BobKos]

I recently installed a Uni-Pre into a Warmoth rear route Jazz Bass. Two issues I had were alignment of components and mounting hole depth. For the giant swimming pool sized cavity I had to work with, I still had to finagle the control boards to achieve the control layout I wanted. More importantly - the threaded area on the pots was so shallow that I had to route additional material out of the cavity in order to properly mount the control pots. IMO John needs to re-visit that aspect of this design. I like the preamp but I guess I am spoiled by the simplicity of the J-Retro amps. All this is from a J.East preamp fanboy.

 

[JC BASS 91]

I recently installed a Uni-Pre into a Warmoth rear route Jazz Bass. Two issues I had were alignment of components and mounting hole depth. For the giant swimming pool sized cavity I had to work with, I still had to finagle the control boards to achieve the control layout I wanted. More importantly - the threaded area on the pots was so shallow that I had to route additional material out of the cavity in order to properly mount the control pots. IMO John needs to re-visit that aspect of this design. I like the preamp but I guess I am spoiled by the simplicity of the J-Retro amps. All this is from a J.East preamp fanboy.

View attachment 5145234

How are your controls laid out?

 

[logdrum]

Custom SingleCut Control layout from top (or left to right when playing)
Vol->Blend->Stacked Bass/Treble-> Stacked Mid/Mid Freq-> Passive Tone Pull/Push active/Passive. It's still tight granted the DPDT switches do take some space

 

[JC BASS 91]

View attachment 5145247

Custom SingleCut Control layout from top (or left to right when playing)
Vol->Blend->Stacked Bass/Treble-> Stacked Mid/Mid Freq-> Passive Tone Pull/Push active/Passive. It's still tight granted the DPDT switches do take some space

Your reply confused me. Turns out that you replied to the question I asked BobKos. I could NOT reconcile your layout with the picture he posted of his control cavity. I was scratching my head until I noticed it wasn't the same person that had posted.

 

[Wfrance3]

Yikes! That does look tiny in there! I have have a Uni-Pre 5 knob in an Ibanez 305F and a 4 knob in a Schecter Elite. Neither gave me grief, although the Ibanez was tricky, I just don't remember the deets. It was at least 10 years ago....
I really liked the tone, obviously b/c I bought this preamp twice...
Is it under a front loaded plate like in post#4? or is t rear loaded like in post #2. If it's rear loaded, you might be able to get someone to route the cavity a little bigger, and then make a replacement cover for the new larger cavity out of pick guard material. Would be invasive, and could be expensive, but that potentially could get the job done for you.

 

[BobKos]

How are your controls laid out?

I set it up like a J-Retro Deluxe. From top (closest to neck) - Vol / Blend > Treb / Bass > Mid Freq / Mid Boost > Passive Tone. The first 3 are stack knob config. I could have made it fit more comfortably, but I didn't want a quirky control setup. I am used to this configuration so I went with it. If I needed to, I would have made clearance routes (tunnels?) under the surface of the front / back faces in order to make enough room.

 

[logdrum]

Your reply confused me. Turns out that you replied to the question I asked BobKos. I could NOT reconcile your layout with the picture he posted of his control cavity. I was scratching my head until I noticed it wasn't the same person that had posted.

I forgot to answer one of your questions. Hence the pic. Earlier I said it will not fit a regular Jazz bass route, no space for batteries and it may not even be deep enough and long enough and the EQ board will be the hardest unless you put the bass/treble stacked first and the EQ board will be under the pickguard. He created this preamp for rear routed basses. Short answer is it won't fit for a traditional control layout. You can route a space towards the back of the bass if you want regular controls V/B -> Mid - Passive -> Bass/Treb. I would sell it and get a J-Retro Deluxe if you want to keep using East.

Question for those that have this preamp in your bass, WHAT bass is it in? A custom build or did you add it to an existing bass? Replace a factory preamp perhaps?

 

[BobKos]

I ended up deciding to leave the stock preamp in the Fender as my main drive to change it out was to have the active/passive option.

I agree with this. The UniPre does have an excellent bypass which many preamps don't including and especially the J-Retro. That reason is why I went through the trouble on my bass above (plus the fact that as in your case I already had the preamp on hand!). Eventually you will run into a bass or body with enough real estate to install it. IMO it will be worth having when you do.

 

[JC BASS 91]

I forgot to answer one of your questions. Hence the pic. Earlier I said it will not fit a regular Jazz bass route, no space for batteries and it may not even be deep enough and long enough and the EQ board will be the hardest unless you put the bass/treble stacked first and the EQ board will be under the pickguard. He created this preamp for rear routed basses. Short answer is it won't fit for a traditional control layout. You can route a space towards the back of the bass if you want regular controls V/B -> Mid - Passive -> Bass/Treb. I would sell it and get a J-Retro Deluxe if you want to keep using East.


View attachment 5145275

Yeah, not sure you read my original post completely. I know it won't fit in my Jazz bass (and don't intend to try and make it), but was wondering where others have installed the same preamp and to see pics of it. I suspected it would have to be in a rear route cavity.

 

[JC BASS 91]

I set it up like a J-Retro Deluxe. From top (closest to neck) - Vol / Blend > Treb / Bass > Mid Freq / Mid Boost > Passive Tone. The first 3 are stack knob config. I could have made it fit more comfortably, but I didn't want a quirky control setup. I am used to this configuration so I went with it. If I needed to, I would have made clearance routes (tunnels?) under the surface of the front / back faces in order to make enough room.

That's what I thought I was seeing in there, but wanted to verify that's what you had done. Thanks!

 

[funkinbottom]

I put one in my own build with Bartolini P2's. Absolutely love the Bart/East combination. And so nice having a passive tone control also.