Volume Problem with Dual EMG 35TW

[jbrooks]

Please help me! I've just completed my epic project bass with dual EMG 35TW pickups, an EMG BTC equalizer, and a hipshot tremolo.

http://stratbass.blogspot.com/

I've chased this problem for a couple of weeks, and I'm hoping someone can help me. The 35TW is a dual coil pickup that can be switched between a single and dual coil. With two of these, you should be able to get a jazz, precision, P/J, musicman, etc sound.

The two pickups are wired parallel, jazz bass fashion. Each pickup should be controlled by it's corresponding volume pot. The neck pickup and pot work perfectly. The bridge pickup only works when the neck pickup is turned on.

I've checked continuity, wired and rewired. Thought I had it isolated to a volume pot: EMG sent a new one and same problem.

I'm waiting for a response from EMG (tomorrow). I made a blog complete with photos of my last troubleshooting session. It's just too much information to send to EMG via email or to post here.

http://installing-emg35tw.blogspot.com/



By the way, the bass sounds AWESOME! I just wished I had the same volume control as my jazz and P/J basses have.

I'm wondering if I need a single volume and a balance control. I would have to install two mini switches to control the single to dual coil selection.

[jbrooks]

anyone?

[JMDT]

Call me crazy, buy how did you wire these in parallel? I thought the EMG TWs had an 8 pin connector or some such, and all the wiring was taken care of inside of the housing and if you used the stock EMG internals, everything should just plug together. You could try a blend pot, but IMHO I don't like EMG's blend pot very well and the varied output of the pickups if in different modes would make it difficuly to operate. To me the blend pot is ony useful at the middle setting or with one on 100%. You would be better off with a pickup switch if you were going to try a blend pot. Some companies like Audere make a buffered blend pot that may fix this problem. If you would like to make the two modes operate at the same volume to better facilitate a blend pot, check this link. http://home.no.net/hhh78/emg-mod.pdf

BTW, how do the TW's sound, I've contemplated putting a set in one of my basses, but didn't know if they were worth the extra cost vs. a CS.

[jbrooks]

Even with the weird electrical problems, these things sound great. With two of them I can get almost every sound I want.

I stand corrected, the pickups are not wired parallel, but the pots are in the standard jazz configuration

[DavidRavenMoon]

I say check the way the volume pots are wired. There's two ways to do it. The way a Jazz bass is done the pickup is wired to the wiper of the pot (center lug) while the output of that pickup is wired from the fully clockwise lug, and ground is the other side.

However, "standard" volume pots are wired to the pickup is connected to the CW lug, while the output is from the wiper. With this setup, turing down one pickup turns them both off, as on a Les Paul.

So it sounds like you have at least one volume control (neck pickup) wired up this way. The EMG pots may have come wired as on a P bass, which is the wrong way compared to a J bass.

Do you have the schematic you used?

Also just to clarify, the TW pickups actually have two separate pickups inside. You never actually switch into single coil mode, you are switching between a EMG-J and a CS. The J is a stacked humbucker. You can actually use both of them at the same time.

How do you like the Hipshot trem? I used to have a Kahler trem on a fretless P/J bass. That was a lot of fun.

[jbrooks]

You are right about the pickups. This is what I meant, but I guess I wasn't clear expressing it.

I've been in contact with Rick Hunt at EMG. He's offered to send me a RMA to send them back and let him look at them.

These pickups come with a push/pull switch; The center lug on one side of the switch connects to the center lug of the pot. This is wired this way from the factory I've posted these diagrams on my blog about this; http://installing-emg35tw.blogspot.com/ along with actual pictures of my wiring and troubleshooting process. Rick from EMG has looked at this and said I've done everything right so far.

I thought maybe the factory wiring was off on the one wiring harness, but after checking the photo in the blog, they are both the same.

Too early to comment about the hipshot so far. I just finally set the intonation and string height. I'll post later about it once I get to play with it some more.

[jbrooks]

Well I finally figured out what was wrong with the electronics. I took it apart again today and tested each pickup and corresponding potentiometer. Each one would work alone but not together. I had replaced the one I thought was bad, so I replaced the other one. I seems it was the one that was bad. It would work by itself but it would cause problems with the other one.

Anyway, it sounds even better now.