More blender blunders: preamp help?

Jeffreykip · #1 11-19-2023, 04:16 AM

Electronics wizards,
I have a new-to-me Esonic2 preamp which blends the mag and under-saddle pickups - except that it doesn't. There are two end-pin jacks, one that should blend the two, and the other, when using both, should make them function as separate stereo outs. My tinkering leads me to believe that whatever mechanism engages the switch between the two functions is screwy and is "stuck" on only the mag out and the under-saddle does not engage, even when I am using the "blend" jack. Any ideas on how to get the "blend" feature to work? Yes, I've tried plugging and unplugging a few jillion times to no avail. Yes, I have fiddled with, cleaned, the blend slider.

I took the preamp out, opened it up and gave it a cleaning.
Both pickups definitely work - the problem is somewhere in the preamp.
With the preamp out of the guitar, I plugged the under-saddle into the preamp where the mag should go, just because I like it better. It's ok, but not a perfect fix. I am also guessing that the preamp is not doing it's best work that way.

If someone understands the switching mechanism from blended to dual-out and can say, "oh, it's as simple as bla, bla, bla-di-bla" that's what I am looking for. I am perfectly happy if it is only blended, I can't see myself ever using the stereo-out function.
Reading this back I see my question is verbose, confusing, and an attempt to fix a pickup with a low performance ceiling, but it is what it is.

Anyone have an idea?

Kip

ps preemptive thought- if your suggestion is dump the mediocre preamp/pickup and install a better one, I hear you and maybe that's what I will do in the end. But, if I can get this to work, that's my preference.

Mandobart · #2 11-19-2023, 07:45 AM

Has it worked correctly before and now doesnt, or has this problem always existed? Can you give any more info on the pickups you're using?

Magnetic pickups have a low output impedance (in the kilohm range). Piezoelectric pickup impedance (like your UST) is 1000 times higher (megohms). Active electronics are required to blend them - they can't simply be wired straight to a stereo jack and then sent on to an amp/PA.

Did you change the battery in your preamp? Have you tried different cables? TRS and TS?

I'm sure I don't fully understand your dual output jack setup. All you should need is a single jack coming from the preamp. Is either one (or both) TRS jacks, with one coming from the preamp and the other a passive TRS? Is this an original configuration or have you modified it? I would think that each pickup signal output should wire straight to the preamp, and the output of the preamp should go to a standard mono (TS) jack. Possibly what you're calling a "stereo out function" is really a TRS jack with a passive signal from each pickup - maybe the mag on the tip and UST on the ring (or vice versa).

When I wired my Eastman archtop with a floating neck magnetic pickup and a piezo SBT I used a single stereo output jack (TRS) with the mag on the tip and SBT on the ring. I use a short TRS cord from the jack to a Baggs Mixpro blending pickup clipped on my belt. I can go all piezo, all mag or blend them. The Mixpro output is TS, not TRS.

Alternately, I could run a TRS (aka stereo cable) from the guitar TRS jack all the way back to my amp, use a TRS to TS Y splitter and plug the tip (mag) into one channel and the SBT (ring) into another. But I find it simpler to use the Mixpro.

Jeffreykip · #3 11-19-2023, 09:22 AM

Thanks for the thought, Mandobart. It's actually two standard 1/4" endpin style jacks. It's not complicated, just more than I could explain in a post, and just overcomplicated enough to make a good idea a bad reality. If you Google the Esonic2, you can see what it is. I don't promise excitement.
Yes, changed the battery, tried different cables, used electric contact cleaner, and all the things one can do if you're not a guitar tech. I just know there is a lot of specialized knowledge around here and I am dreaming that I might get a "that happens all the time, and the simple fix is..."
What will probably happen is that I just never use the mag and use the undersaddle, but I'd like to hope for more.

Mobilemike · #4 11-19-2023, 01:02 PM

A little googling found this on the Gibson forum:

When you have have separate leads from each socket only the signal from the Nanoflex is routed to the socket marked Both Pickups and only the Nanomag signal is routed to the socket marked Stereo/Nanomag. When there is no plug in the Stereo/Nanomag socket the signal from both pickups is routed to the Both Pickup socket.

https://forum.gibson.com/topic/61551-esonic2/

Jeffreykip · #5 11-19-2023, 03:53 PM

Quote:

Originally Posted by Mobilemike

A little googling found this on the Gibson forum:

When you have have separate leads from each socket only the signal from the Nanoflex is routed to the socket marked Both Pickups and only the Nanomag signal is routed to the socket marked Stereo/Nanomag. When there is no plug in the Stereo/Nanomag socket the signal from both pickups is routed to the Both Pickup socket.

https://forum.gibson.com/topic/61551-esonic2/

Yea, that's just describing what should happen, but it is not.