freestompboxes.org

CHEEZOR wrote:

slammer88 wrote:https://www.diystompboxes.com/smfforum/ ... ic=94138.0

got the similar problem with this guy ^^

"but there will always be a difference "hands up" vs. "hands down" when the bridge is grounded." is that true? if yes, how is this elimininated in EMG's ?

This is eliminated in EMG's because the bridge / strings are not grounded. Therefore, you will hear no difference between when your hands are touching the strings and when your hands aren't on the strings because they are not a part of the circuit. They are also extremely quite pickups so there isn't much noise either.

ah..true..so, what if i..disconnect them?

slammer88 wrote:ah..true..so, what if i..disconnect them?

Your hands or the strings / bridge?

CHEEZOR wrote:

slammer88 wrote:ah..true..so, what if i..disconnect them?

Your hands or the strings / bridge?

The connection between bridge and ground

slammer88 wrote:..so, what if i..disconnect them?

Try it and see. It might be better, it might be worse.

At 250 ohms it is not a very good connection anyway. It might just be upsetting the balance of the 2 coils into the differential amplifier so they are no longer hum-bucking.

deltafred wrote:

slammer88 wrote:..so, what if i..disconnect them?

Try it and see. It might be better, it might be worse.

At 250 ohms it is not a very good connection anyway. It might just be upsetting the balance of the 2 coils into the differential amplifier so they are no longer hum-bucking.

This humming was there before connecting the preamp, as well. And i think i should remember that, at the guitar chain there's an overdrive + hi-gain amp sim enabled on my sound demo

Hi guys,
I have a big issue about baja preamp. I connected preamp with bridge pickup but I got poor signal there was no change I tried 3 opamp lf442,tl071 and tl061 step by step.. I got no response, only same reading.In addition, it is weird that when I removed opamp I got same poor signal..ıt continued working
I need help about connection. please help me!!! by the way, my pickup cover is chome and when I touch the pickup a strange pickup noise appears..
I need solutions..Please....I need detailed wiring document..
Thanks..

gmulak wrote:Hi guys,
I have a big issue about baja preamp. I connected preamp with bridge pickup but I got poor signal there was no change I tried 3 opamp lf442,tl071 and tl061 step by step.. I got no response, only same reading.In addition, it is weird that when I removed opamp I got same poor signal..ıt continued working
I need help about connection. please help me!!! by the way, my pickup cover is chome and when I touch the pickup a strange pickup noise appears..
I need solutions..Please....I need detailed wiring document..
Thanks..

It might help if you could post a detailed close up picture of the wiring that you have right now.

Here is my wiring diagram. Any ideas? Solutions? If you can't see the schematic, use this link:

http://d1202.hizliresim.com/u/4/2dprk.jpg

I checked the preamps and its ok, working

I need help! Please

I don't see how battery -ve/ground gets to the preamps (unless I am missing something completely obvious).

deltafred wrote:I don't see how battery -ve/ground gets to the preamps (unless I am missing something completely obvious).

I connected the battery ground to the ring( on the guitar output). Shall I make connection with preamp ground section?

gmulak wrote:

deltafred wrote:I don't see how battery -ve/ground gets to the preamps (unless I am missing something completely obvious).

I connected the battery ground to the ring( on the guitar output). Shall I make connection with preamp ground section?

Connect the "ring" connection on the jack to both preamp ground points (the track marked "G" on Baja's PCB layout).

Thanks for the help I'll try it tonight I m gonna share the results..
Cheers!

deltafred wrote:

gmulak wrote:

deltafred wrote:I don't see how battery -ve/ground gets to the preamps (unless I am missing something completely obvious).

I connected the battery ground to the ring( on the guitar output). Shall I make connection with preamp ground section?

Connect the "ring" connection on the jack to both preamp ground points (the track marked "G" on Baja's PCB layout).

I did as you said but it didnt work,regrettably When I touched the pickups, I got strange noise like humming That is my guitar above, it has chrome pickup cover..I think there is no way to kill the hum.. Weird!! Any changes?

gmulak wrote: Thanks for the help I'll try it tonight I m gonna share the results..
Cheers!

i've just looked at your diagram again and didn't notice the first time. You have your jack socket wired incorrectly.

You have the battery -ve to the tip, it should be to the ring, and the signal to the ring (centre connection) this should be to the tip.

The ground supply to the preamp boards should be connected to the jack screen (body), not the ring I said earlier. Sorry I missed it before.

Hope you follow that.

Hey again. I've applied this preamp to my Bass guitar, and as i want to prevent the drain of 9V, i've bought a stereo jack to use its "ring" lug. However, i've faced a problem. When i connect the 9V's negative lug to ring "directly", it will not give any sound at all, but if i make the connections like i did in the attachment, it works fine but i'm not sure either the circuit still works when disconnected or not. My pickup has 4 cables, black, yellow, and soldered red-white. You can see the connection i've made at the attachment. If i separate the red-white lugs, connect them to IN + and IN - and solder the negative lug of 9V to "ring", it works, BUT it has halfway less gain than it has with the previous connection..

What's wrong?

and shall i change the volume pot into a 25k both for my guitar and bass?

slammer88 wrote:and shall i change the volume pot into a 25k both for my guitar and bass?

Get it working first.

The battery -ve ONLY to the "ring" connection, all other ground connections to the "sleeve".

This is so that when you insert a mono jack it shorts the ring to sleeve connections and connects the battery to the preamps.

deltafred wrote:

slammer88 wrote:and shall i change the volume pot into a 25k both for my guitar and bass?

Get it working first.

The battery -ve ONLY to the "ring" connection, all other ground connections to the "sleeve".

This is so that when you insert a mono jack it shorts the ring to sleeve connections and connects the battery to the preamps.

Agreed. That is the correct way to wire it. And the 25k pots should only be used if you are unhappy with the sound once everything is functioning properly. I have an EMG 81/85 set in a guitar and I used 1 master volume + master tone that was 500K, and then a push pull to route the signal through a 25K master volume + master tone combo so I could A/B them easily. As it turns out, I never use the 25K route since there is significantly less volume and I wanted a balls-out metal sound with that guitar.

deltafred wrote:

slammer88 wrote:and shall i change the volume pot into a 25k both for my guitar and bass?

Get it working first.

The battery -ve ONLY to the "ring" connection, all other ground connections to the "sleeve".

This is so that when you insert a mono jack it shorts the ring to sleeve connections and connects the battery to the preamps.

Well then, as i've said, if i connect the -ive lug to "ring" and use "yellow" cable as out, i can't get any sound from guitar, but if i use use red-white cables, i get a sound but its significantly weaker that it was on yellow..

You can see my

slammer88 wrote:

deltafred wrote:

slammer88 wrote:and shall i change the volume pot into a 25k both for my guitar and bass?

Get it working first.

The battery -ve ONLY to the "ring" connection, all other ground connections to the "sleeve".

This is so that when you insert a mono jack it shorts the ring to sleeve connections and connects the battery to the preamps.

Well then, as i've said, if i connect the -ive lug to "ring" and use "yellow" cable as out, i can't get any sound from guitar, but if i use use red-white cables, i get a sound but its significantly weaker that it was on yellow..

You can see my

Solved! I was using a wrong lug. A multimeter solved my problem..

"mono jack it shorts the ring to sleeve connections and connects the battery to the preamps"

i've checked the lugs, and saw, two of them are connected when a mono jack plugged in, but disconnected when its plugged out

According to this, the