$8 Chinese Preamp... No instructions (of course)

[MovinTarget]

Ebay purchase for a budget frankenbass.

Edit: Dug up the original link, says that wiring diagram is included lol
Mings 3 Band EQ Circuit Preamp Set For Active Bass Pickup Profession New 664879126911 | eBay

Now this should NOT be rocket science, I get that, however... If I've purchased a pre-wired circuit, is there any way to determine what is what?

It is a V/B + H/M/L 5-pot, 3 band EQ system with 3 of the pots being wired to the preamp box in similar fashion make them obviously the H/M/L... (apart from having to determine which band is which!).

The other 2 pots... I'm assuming the one with 2 sets of contacts is the balance pot, they contacts are stacked three & three. Can I assume the top set (nearest to the post) are for the neck pickup and the bottom for the bridge?

Is there any way to determine the wiring schematic if there was nothing sent so I can set this up easily?

Any generic assumptions? (other than you get what you pay for? lol)

Thanks!

 

[Xapt]

any pictures would be useful.

 

[MovinTarget]

I will see if I can take some later today.

Thanks

 

[dreamadream99]

Ebay purchase for a budget frankenbass.

Now this should NOT be rocket science, I get that, however... If I've purchased a pre-wired circuit, is there any way to determine what is what?

It is a V/B + H/M/L 5-pot, 3 band EQ system with 3 of the pots being wired to the preamp box in similar fashion make them obviously the H/M/L... (apart from having to determine which band is which!).

The other 2 pots... I'm assuming the one with 2 sets of contacts is the balance pot, they contacts are stacked three & three. Can I assume the top set (nearest to the post) are for the neck pickup and the bottom for the bridge?

Is there any way to determine the wiring schematic if there was nothing sent so I can set this up easily?

Any generic assumptions? (other than you get what you pay for? lol)

Thanks!

Move that second wire to the 5th lug, and tandem solder it with the ground. Then, take that dangling green wire, and splice it in on the ring of the input jack. And finally, add a 500 Ohm resistor between the orange wire, and the first post of the second pot.

 

[MovinTarget]

The whole assembly:

Below... Balance is top pot and Volume bottom right? On that top pot it has 2 rows of contacts, top for Neck pup and bottom for Bridge?

 

[Crater]

Balance is top pot and Volume bottom right? On that top pot it has 2 rows of contacts, top for Neck pup and bottom for Bridge?

Yes. The pickup "hots" go to the center terminals on the balance pot. The pickups grounds can be connected to any convenient grounding point, like the back of the volume pot.

 

[MovinTarget]

Yes. The pickup "hots" go to the center terminals on the balance pot. The pickups grounds can be connected to any convenient grounding point, like the back of the volume pot.

Thanks!

That's what I wanted to know for sure, I can fiddle with the EQ to figure out which is high/low/mid (I'm guessing middle pot is mid...)

BTW, found the link:
Mings 3 Band EQ Circuit Preamp Set For Active Bass Pickup Profession New 664879126911 | eBay

 

[Crater]

Just so you don't have to take my word for it...

Image taken from this page: Invalid Link Removed

 

[kodiakblair]

Great little preamp. I've stuck them in plenty basses and they work just fine

 

[MovinTarget]

Great little preamp. I've stuck them in plenty basses and they work just fine

Great to hear! Did you happen to get any documentation with yours that might indicate anything "non-conventional" or how to tell which pots are which among the 3 bands?

 

[kodiakblair]

Sorry @MovinTarget can't help with that,they just came in plastic bags.

The "Mings" also gets sold as "Belcat". Pretty straight forward preamp found in bass guitars these days.
Just hook it up as @Crater described and you're good to go.

 

[DooglieBop]

Great little preamp. I've stuck them in plenty basses and they work just fine

I have the hots(white wire) connected to the middle terminals and have the negatives twisted with what i assume to be grounds for each pickup together and sodered them separately ( and neck p-upbridge p-up) to the volume pot. So im left with 2 black wires, one from the 9v and the other from the black box(holding all wires). I know one goes to the input jack and but does the other act as a ground? And where should i connect it? Ive tried all i can think of but obviously something isnt correct it just clicks a bunch as i move the wires around and no signal.

 

[kodiakblair]

I have the hots(white wire) connected to the middle terminals and have the negatives twisted with what i assume to be grounds for each pickup together and sodered them separately ( and neck p-upbridge p-up) to the volume pot. So im left with 2 black wires, one from the 9v and the other from the black box(holding all wires). I know one goes to the input jack and but does the other act as a ground? And where should i connect it? Ive tried all i can think of but obviously something isnt correct it just clicks a bunch as i move the wires around and no signal.

The other black should be your bridge ground. There will be a wire coming from the bridge direction so splice the two together.

 

[Matt Liebenau]

I have the hots(white wire) connected to the middle terminals and have the negatives twisted with what i assume to be grounds for each pickup together and sodered them separately ( and neck p-upbridge p-up) to the volume pot. So im left with 2 black wires, one from the 9v and the other from the black box(holding all wires). I know one goes to the input jack and but does the other act as a ground? And where should i connect it? Ive tried all i can think of but obviously something isnt correct it just clicks a bunch as i move the wires around and no signal.

Going by your description and not having the bass in hand (so I could be utterly mistaken) the black wire from the box would go to the sleeve connection on the jack and the black wire from the battery goes to the ring connection (you do have a TRS or stereo jack, right?).

 

[DooglieBop]

It came with a cheap TRS but i planned on switching it to the original cylinder style that came installed after i get the wiring sorted out. Thank you for your reply, this thing bested me 3 times already and i was on a hate train all day

 

[DooglieBop]

The other black should be your bridge ground. There will be a wire coming from the bridge direction so splice the two together.

YESS OF COURSE! Now that makes perfect sense. I havent tried that but plan on giving it another round in the morning. Thank you so much for your reply i was about to lose my s*** lol. Ill let y'all know how it turns out!

 

[kodiakblair]

Look forward to hearing your thoughts on it.

 

[DooglieBop]

Look forward to hearing your thoughts on it.

We got a winner! Well 2 of them! You were correct, its working and i got it all put back together. Sounds like doodoo and the controls hardly have an effect on the signal shaping and sounds kinda distorted but considering the price i got what i paid for. Im just glad i got it bumping again, ive had this bass for a really long time so its sentimental to me. Thank you for your help i truly appreciate it.

 

[MovinTarget]

We got a winner! Well 2 of them! You were correct, its working and i got it all put back together. Sounds like doodoo and the controls hardly have an effect on the signal shaping and sounds kinda distorted but considering the price i got what i paid for. Im just glad i got it bumping again, ive had this bass for a really long time so its sentimental to me. Thank you for your help i truly appreciate it.View attachment 3440121

I liked it not because "it sounds like doo doo" but because I'm happy you could get some help!

 

[DooglieBop]

Thank you for the likes! I got a TB Trophy