*HELP! Installing Hot Rails to EQ/preamp!

Inoran

New member
I just bought a hot rails neck pickup to replace my lipstick pickup on my Crafter SA acoustic/electric ( http://www.crafterguitars.com/gallery_acoustic/sa_tmbk.php ). The lipstick pickup that came with the guitar had a 2.5mm jack on the end that simply plugged into the the preamp/EQ while another wire was grounded. I chopped off the 2.5mm jack and soldered it to the black wire on the hot rails and have taken the red and white wires and twisted them together then used liquid rubber electrical seal to isolate the ends together. Now I plan to just take the bare and green wires and ground them to say...maybe a screw or a nut somewhere. My question is will this work? Is there any reason that soldering the black wire to the 2.5mm jack and plugging that into the preamp wouldn't work? The preamp takes a 9v battery and the Hot Rails is passive so does that matter? Also does it matter where I ground and how much/what type of metal is used?

Note: This guitar also has a L.R. Baggs Acoustic Piezo Element pickup that plugs into the EQ/preamp via 2.5mm jack. I plan to blend the two to try and get some acoustic sounds with some screaming harmonics from the Hot Rails.

I am a total noob and have never done this before so any help would be greatly appreciated.
 
Last edited:
Re: *HELP! Installing Hot Rails to EQ/preamp!

Welcome to the forum.

For several reasons, the tidiest solution would have been to solder the SD pickup to a new 2.5mm jack plug.

The stock pickup and the SD replacement are both straightforward magnetic types. The Crafter PCB will be designed to handle the buffering between the active and passive stuff.

As for screaming harmonics, you are going to get plenty of those. On an electro-acoustic hollow bodied guitar, the Hot Rails pickup is going to howl. Balancing the levels between piezo and magnetic is going to be tricky.

Your call.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Welcome to the forum.

For several reasons, the tidiest solution would have been to solder the SD pickup to a new 2.5mm jack plug.

The stock pickup and the SD replacement are both straightforward magnetic types. The Crafter PCB will be designed to handle the buffering between the active and passive stuff.

As for screaming harmonics, you are going to get plenty of those. On an electro-acoustic hollow bodied guitar, the Hot Rails pickup is going to howl. Balancing the levels between piezo and magnetic is going to be tricky.

Your call.

THank you SO much for your response. I already chopped the 2.5mm jack from the lipstick pickup and soldered the black wire from the SD to it. WHen I plug it in and test it (unstringed and just tapping the pickup blade with a screwdriver) I get no sound or anything. Is this because I didn't use a brand new jack? Is there any trick to grounding it? I just have the ground wires touching a piece of metal while trying to test.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Was the 2.5mm jack plug the sealed plastic type or one with a threaded outer barrel that can be removed to expose the soldering terminals?

In the former instance, you need a DC resistance meter in order to establish which wire into the jack connects to which contact on the plug.

i suspect that your signal and ground connections are made to the wrong contacts.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Was the 2.5mm jack plug the sealed plastic type or one with a threaded outer barrel that can be removed to expose the soldering terminals?

In the former instance, you need a DC resistance meter in order to establish which wire into the jack connects to which contact on the plug.

i suspect that your signal and ground connections are made to the wrong contacts.

There was no threaded barrel just the jack itself with what appears to be a small metal capsule around it that the original wire was soldered to that had a rubber wrap around it. Here is a picture of what it looks like now.
2012-12-04_23-16-09_87.jpg
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

I am trying to figure out where the tip/sleeve (mono) jack in the photograph has its second terminal? I can only conclude that the plug is coaxial and that some of it is missing.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

i would assume that the green wire needs to go to the sleeve of the jack and the black wire to the tip.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

i would assume that the green wire needs to go to the sleeve of the jack and the black wire to the tip.

Thank you both for your help. Which jack are you talking about though? The two smaller holes in the picture are for the pickups (2.5mm). The larger hole is the for a 3.5mm jack, which is wired to go to the 1/4" hole for the amp cable (not pictured).

I am a little confused what you guys mean by the sleeve and the tip. Could you guys specify a little more? I can't imagine how you would plug the jack in if it had a wire soldered to the tip. I have noticed that on the end of the piezo pickup, the 2.5mm jack has a screw on barrel like funk was talking about. Here is a picture. 2012-12-05_11-27-57_684.jpg

What do you guys suggest i try?
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Okay guys here is an update. I learned about the sleeve and tip aspects of headphone jacks. Went up to radio shack and got a 3/32 phone jack (same size as 2.5mm), I soldered the black (hot) wire to the tip, and put the green wire on the sleeve. I tested it and I've got sound when I tap the pickup with a screwdriver! My only question now is what do I do with the bare wire? Should I ground it seperately to a piece of metal or do I ground it to the sleeve with the green wire? All the schematics for using the hot rails pickup conventionally show the green and bare wires both going to ground. So is that what I should do? Seems to make noise when tapping whether the bare is touching anything metal or not...

Thanks again guys. You've got great karma coming your way. The little tidbits you left really made a difference.
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Inside the jack plug, there will be two contact points. You have already identified the hot/tip terminal. The green and bare wires both need to be connected to the second contact point. Make certain that the wires are insulated before refitting the outer part of the metal plug. (There could well be a section of plastic tubing supplied for precisely this purpose.)
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

You've got great karma coming your way.

My outlook is a combination of Bill Hicks… "If ya smoke, ya die. If ya don't smoke, ya die."

…and Benjamin Franklin. "Nothing can be said to be certain, except death and taxes."
 
Re: *HELP! Installing Hot Rails to EQ/preamp!

Ok got it hooked up and working AND.....boy are those babies hot. Even fading them to 95% Acoustic pickup and 5% hot rails is overwhelming. Any ideas for turning up the acoustic pickup or turning down the hot rials?
 
Back
Top