Author Topic: Alembic Newbie with a Pickup Problem (Read 954 times)

doctor_hugocat · « **on:** June 10, 2015, 04:45:58 PM »

I'm a complete newbie to the Alembic world: however I have a problem with my Alembic PUPs and wonder if anyone can help....I'd love to get them working right!

Here's my situation. A bass-playing friend of mine has offered to sell me his Alembic jazz pickups and preamp. He's had them many years and they've been in a drawer for three or four. He lent them to me to see if I liked them. I fitted them, put a battery on and they work well seperately: but not together. When the bridge PUP is all the way down, the neck PUP sounds GREAT. When the neck PUP is all the way down, the bridge PUP sounds pretty good. But when both PUPs are on full, the sound gets muddy and bland. If I back the bridge PUP off even a little bit, I can hear immediate improvement: the volume, tone and definition come back into the sound. But on both full, it goes 'dead' again.

Can anyone help out? I love each PUP when it's soloed, but the sound of both together is disappointing. Backing the bridge off helps, but it then doesn't get as much 'snap' in the sound as I'd expect. Tone control works fine throughout. Any thoughts appreciated - I'd love to become a permanent Alembic addict!!

keith_h · « **Reply #1 on:** June 10, 2015, 05:08:42 PM »

Just off the top of my head it sounds like the pickups might be out of phase. A picture of the controls and wiring would also be helpful.

Keith

doctor_hugocat · « **Reply #2 on:** June 10, 2015, 05:26:26 PM »

Hi Keith- many thanks: I'll take out the preamp this evening, check the phase and take a photo of the preamp. Much appreciated!

doctor_hugocat · « **Reply #3 on:** June 10, 2015, 10:36:02 PM »

OK, I check the phase: I soldered the wires right and the little plugs are in the preamp the right way round: so I guess that's OK. Here are 2 pics of the preamp. Thanks!

(Message edited by davehouck on June 11, 2015)

mica · « **Reply #4 on:** June 10, 2015, 10:38:32 PM »

Hmmm... If you have the volume on both pickups at about 90%, how does it sound?

doctor_hugocat · « **Reply #5 on:** June 11, 2015, 12:21:57 PM »

Thanks mica, good question: I experimented just now and no, it appears that backing off either (or both) pots just slightly takes away the volume drop and flatness. I can play it this way (wow the neck PUP is SO good!) but I'd still love to be able to play it all the way 'open' if I can.

mica · « **Reply #6 on:** June 11, 2015, 02:37:16 PM »

Well, I think everything is sorta working the way it is supposed to. There's more than one reason we don't make this exact setup anymore. If you're game to cutting traces and soldering some resistors, we can help you modify what you have so that at full volume it only gets to 90% so you don't bump into that icky sound. We can also do the work for you.

Another option is to ditch the 2-volume set up and swap it out for a volume/pan. The only electronics you will keep is the preamp, but then you can keep what you have there as emergency spares. Email me (in profile) if you would like to discuss any of these options.

(Message edited by mica on June 11, 2015)

slawie · « **Reply #7 on:** June 11, 2015, 04:55:55 PM »

Is the blue pot the balance between pickups or output level?
I am wondering if adjusting that blue pot makes any difference?
Mark it before you move it so as to get back to the same place.

mica · « **Reply #8 on:** June 11, 2015, 05:01:30 PM »

It's the overall gain - it will impact both pickups the same amount.

BTW, the date code indicates these electronics were made in December 1984.

doctor_hugocat · « **Reply #9 on:** June 12, 2015, 11:10:19 AM »

Thanks guys - Mica, I'll email you. The idea of a volume/pan is VERY ATTRACTIVE!!

I love these PUPs so much.....I really want to get them working at their fullest potential.

hieronymous · « **Reply #10 on:** June 12, 2015, 09:48:03 PM »

First of all - congrats on the Activators! I have two Fender basses with Activator setups - one with just a P pickup and one PJ.

An important thing to remember is that, since these pickups are active, you don't have to turn them all the way up. I am totally a passive electronics guy, except with my Alembic stuff. With passive setups, all the way up is basically zero - the full sound - when you turn it down you are losing something. But with active setups, you are getting the full signal no matter where you set the volume. It took me a while to get used to this, but now I have my Alembic volumes set somewhere around 50-60% - I adjust the knobs so that they are pointing towards a screw so I know where that setting is. Basically, you are getting the full potential of the pickups and electronics no matter where the volume is set.

You really want to get used to this where the filters are concerned - they are not like passive tone knobs, you are not going to want to set them at 10 unless you only want that sound. But then you are missing out on the whole range of frequencies.

Good luck with your new pickups and electronics!!! Dig around the club, there are some great posts about the basic philosophy of Alembic electronics and the filter system.