Author Topic: Series 2 wiring issues (Read 339 times)

kkustums · « **on:** July 10, 2013, 12:33:47 PM »

I haven't had this series 2 for long. It is a late 70's. The selector switch only works on one setting. I have a cable wired from stereo to mono so I can play it through any amp. Just wondering if the selector switch can go bad or if I have bad wiring?

JimmyJ · « **Reply #1 on:** July 10, 2013, 03:43:13 PM »

Kenneth, welcome to the forum. Your initiation is complete with the accidental double post. Ha!

We love this kind of puzzle, you've come to the right place. I'm not sure what year Alembic made the 1/4 jack mono but presuming yours is stereo: if you run a normal (mono) guitar cable from the instrument's 1/4 jack to the amp, what happens?

The pickup selector switch should have 4 positions:
1. Off
2. Bridge pickup only
3. Both pickups
4. Neck pickup only

And with a mono cable two of those positions should produce sound at the amp. It will only be the sound of one pickup and I think the neck pickup was tip (but I'm not sure). If it is the neck pickup, then positions 3 and 4 above should both work.

It is possible for that selector switch to fail but it's pretty rare.

Tell us more!

Jimmy J

kkustums · « **Reply #2 on:** July 12, 2013, 04:46:35 AM »

Thanks for the double post death trip. I tried getting rid of it, but couldn't figure it out. oh well.

I have the stereo jack, a mono cable would only pickup one pickup in one position on the switch. When I made a cable to go from 1/4 stereo to 1/4 mono, all the pickups work in one position. The other 3 spots on the selector are dead.

Also, do I need the power supply to run the cool leds on the neck? I think I do and figured an oh well there since I don't have the power supply. The man I bought it from said he had that stuff years ago, but no clue now.

kkustums · « **Reply #3 on:** July 12, 2013, 05:26:23 AM »

kkustums · « **Reply #4 on:** July 12, 2013, 05:28:29 AM »

JimmyJ · « **Reply #5 on:** July 12, 2013, 10:33:27 AM »

OK now your just teasing us. Please post a pic of the front of the instrument too so we can admire your acquisition!

You are correct, the LEDs won't run off battery power. In fact the preamp board itself draws quite a bit of current so I always considered the batteries a backup to the PSU... It's fun to have those LEDs too so you might want to save up for a DS-5.

The flatpack chips on your board and the coaxial pickup connectors make me think it's early 70's. But the small Q pots do make it a Series II. I didn't realize those two features overlapped, I thought by the time Series II started they were already using chips in sockets...

Anyway, here is an explanation of the controls (although your pickup selector switch may be in a different location):
http://club.alembic.com/Images/16271/41122.html?1182027166

Your audio problem is a mystery. But if your stereo to mono cable allows you to hear both pickups (individual pickup volumes change the balance?) that would indicate everything is working properly - except maybe that pickup selector switch. And at least you can play the instrument as it is. Out of curiosity, which switch position is the one that works?

By the way, did you include a couple summing resistors in your stereo to mono cable? (http://club.alembic.com/Images/16271/24370.html?1138068087) Preamp outputs don't like to be connected directly to each other.

And if you were so inclined, here is a description of how to make the internal 1/4 jack mono:
http://club.alembic.com/Images/16271/29811.html?1152754164

Others here should chime in with some ideas too. More pics please!!!

Jimmy J

kkustums · « **Reply #6 on:** July 12, 2013, 10:58:33 AM »

Thankyou thankyou. The switch is 2 if you go counterclockwise. Its very odd. I have been playing this way for a while since it has both pickups playing an sounds great with both. I never worried. I am planning to sell it because i am mooving and thats why i want it perfect for the buyer. I will put the resistors in tonight on the cable and post a pic of the front later tonight.

cozmik_cowboy · « **Reply #7 on:** July 12, 2013, 02:07:08 PM »

I seem to recall Mica saying that they always made them with both switches & QVCs, but didn't formally designate them as Series I & II for a few years. And you're right, we do need lots more pix!!!
And Kenneth - I'll be happy to save you the trouble of moving it or selling it; reply to e-mail in my profile for shipping info

Peter

kkustums · « **Reply #8 on:** July 12, 2013, 07:18:36 PM »

[pictures aligned vertically] (Message edited by adriaan on July 15, 2013)

terryc · « **Reply #9 on:** July 15, 2013, 01:10:55 AM »

Damn nice bass!!!!!!!!!!!!!!!!!!

hammer · « **Reply #10 on:** July 15, 2013, 07:17:15 AM »

Beautiful bass! If this is the same Series II listed in TalkBass I'm surprised you haven't sold it yet.

hammer · « **Reply #11 on:** July 15, 2013, 07:17:29 AM »

Beautiful bass! If this is the same Series II listed in TalkBass I'm surprised you haven't sold it yet.

kkustums · « **Reply #12 on:** July 15, 2013, 02:33:14 PM »

Yea. Same bass. I have had offers of other instruments. I need $$$ because of moving soon.

JimmyJ · « **Reply #13 on:** July 15, 2013, 04:10:59 PM »

Yes, very nice! That's not the original knob on the selector switch so it makes me wonder if it's the original switch?

Jimmy J

kkustums · « **Reply #14 on:** July 15, 2013, 05:52:22 PM »

The outer plastic came off the knob, it has the center metal piece of the knob there.