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tgms
New
Username: tgms

Post Number: 1
Registered: 4-2013
Posted on Saturday, April 13, 2013 - 5:15 pm:   Edit Post

Hi, I am new to this awesome wealth of knowledge. Been reading through alot of this stuff and what a great group of people. I have a question that does not seem to be answered anywhere, even in the manuals, and I feel like a total retard for asking this, but - I repaired a broken headstock on a 1974 Series I bass. The neck is repaired, but all 3 of the connection pins in the cavity were unplugged before I got it, and in checking the electronics I am having the most maddening time figuring out the 4 way switch and the pickup connections. One thing would explain the problem to a degree - did this bass originally come with a stereo to mono 1/4" cord? There is not one in the case. The 5 pin is there. The DS-5 is in the case too but does not seem to be operational. When I plug a mono cord into the jack and then into an amp and start trying to figure the correct lead to the correct output on the motherboard, I get the weirdest things happening, like the bridge pickup working ONLY when plugged into the neck pickup, or the volume for the neck pickup controlling everything, and the only thing I can think of from reading all the posts here is that I definitely need a stereo to mono 1/4" jack, but before I go buy one, or make one in my shop, I wanna make sure its not something else. And Alembic is my idol, and I have never owned one, and I feel like an idiot for not knowing this. I sent an email to Mica, but I am sure they are swamped. Can someone help me? I might have follow up questions.
tbrannon
Senior Member
Username: tbrannon

Post Number: 1554
Registered: 11-2004
Posted on Saturday, April 13, 2013 - 6:32 pm:   Edit Post

Kevin,

Welcome!

I'm not one of the electronics wizards here, but I'm sure someone will be along shortly who will have some specific Series I advice for getting things operational.

Pictures are always good if you have some.

Toby
keith_h
Senior Member
Username: keith_h

Post Number: 1861
Registered: 2-2005
Posted on Saturday, April 13, 2013 - 8:11 pm:   Edit Post

The early Series instruments were stereo only and use a TRS 1/4" connector. Some have been rewired to mono but yours does not sound like this was done.

Instead of using a stereo to mono cable you can try using a pair of stereo headphones. The preamp has enough output that you should be able to use those to get things setup.

Keith
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 3427
Registered: 6-2002
Posted on Saturday, April 13, 2013 - 8:20 pm:   Edit Post

i'm no expert on the older alembics but I'm fairly sure that the jack output is only one pickup when using a standard jack cable and both pickups are only available as standard by using the DS-5. There are some threads on the forum about making a stereo to mono jack lead to get both pickups being output but I'm not sure if you would need to change the jack socket on the bass as well.

As Toby says pictures of your electronics cavity would help one of the members give you better advice than I can before mica has a chance to evaluate your situation.
Welcome to the forum by the way.

Jazzyvee
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 1063
Registered: 8-2005
Posted on Sunday, April 14, 2013 - 4:20 am:   Edit Post

I've got a 76 Series 1.
The jack is stereo! If you plug a mono lead in, you will only get 1 pup working.
Get a stereo to mono cable made up, with the addition of 2x 20 Mohm resistors added to each of the terminals of the mono section of the jack.
As long as you van see that you've got the hum canceller plugged in to the middle set of prongs/bullet connection, then it doesn't matter which pup is plugged into each receptor.
Selector wise................. (for mine anyway)
fully anti clockwise---Stand by.
move forward 1 notch....bridge pup
another notch forward...both pups
Last position (fully clockwise)...bridge pup.
I LIKE it like that, but you can reverse the pup connectors to suit. It makes NO DIFFERENCE to the sound.
When setting up the "holes" in the back plate............the 2 OUTSIDE screws are for the volume of each pup, while the 2 INSIDE screws are for the hum cancelling settings.
How I do this, is to turn both screws fully counter clockwise.
Select 1 pup ONLY at a time, and adjust the hum canceller til you get the least hum..........best to go just past the position and then come back to the ideal setting.

Do the same with the other pup!
I found the best method was to stand real close to the TV so that I got maximum interference, and adjusted it that way. Even on an old 76,.........it's real quiet
tgms
New
Username: tgms

Post Number: 2
Registered: 4-2013
Posted on Sunday, April 14, 2013 - 9:18 am:   Edit Post

Man, thanks a lot. Mica has written back to me a couple times. Obviously Alembic works 7 days a week just like I do... Here are a couple before and after photos of the headstock. .Chris Herrod at LMI was kind enough to take the time to perfectly match the top plate, which we replaced with new zebrawood, as the break went all the way through the faceplate. After "aging" the finish, we ended up with a perfect match. My client doesn't want to alter the internal wiring, so I'm making a cable for him to plug and play mono, as per his wishes. Thanks for all the help, man. Wish I could keep this bass. Bass is my main instrument....Before
tgms
New
Username: tgms

Post Number: 3
Registered: 4-2013
Posted on Sunday, April 14, 2013 - 9:22 am:   Edit Post

After We were obviously really lucky with the break line on the back, and kept the back plate.
tgms
New
Username: tgms

Post Number: 4
Registered: 4-2013
Posted on Sunday, April 14, 2013 - 9:27 am:   Edit Post

Here's the front. I love the little anomalies on the the tip. We rubbed it out by hand to match the aging of the rest of the body, so it wouldn't look too "new." After2
mario_farufyno
Senior Member
Username: mario_farufyno

Post Number: 931
Registered: 9-2008
Posted on Sunday, April 14, 2013 - 9:55 pm:   Edit Post

got curious about what clear wood is that on its fretboard...
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 1064
Registered: 8-2005
Posted on Monday, April 15, 2013 - 12:32 am:   Edit Post

Hey Kevin,
Meant to say in my post above, that the resistors are 20 K ohms and not 20 M
It is one resistor per wire ie 1 for the hot lead, and one for the ground. So only 2 resistors needed.
Just incase you thought it might be 4. Sorry for any misunderstanding. It's these Scottish keyboards......they Kant spelll or rite for tofffay!

George
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 1065
Registered: 8-2005
Posted on Monday, April 15, 2013 - 12:38 am:   Edit Post

Kevin,
I've been at it again!
Meant to say in my post 1063 above, that the selector switch in the fully clockwise position is for the NECK pup and not the Bridge pup again as it seems that some lunatic Scotsman wrote.
Check out my profile pic to see the Zebrawood on my Series 1
mario_farufyno
Senior Member
Username: mario_farufyno

Post Number: 933
Registered: 9-2008
Posted on Monday, April 15, 2013 - 6:04 am:   Edit Post

I'm always learning new things about Alembics, how vast and depth can a Bass be?
keith_h
Senior Member
Username: keith_h

Post Number: 1862
Registered: 2-2005
Posted on Monday, April 15, 2013 - 6:25 am:   Edit Post

The stereo to mono wiring instructions are here.

Keith
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 1067
Registered: 8-2005
Posted on Tuesday, April 16, 2013 - 3:28 am:   Edit Post

That's what I was trying to say!
Thanks Keith.

G
terryc
Senior Member
Username: terryc

Post Number: 2073
Registered: 11-2004
Posted on Tuesday, April 16, 2013 - 6:52 am:   Edit Post

That is a good repair, did you use standard wood glue or something more substantial??
tgms
New
Username: tgms

Post Number: 5
Registered: 4-2013
Posted on Tuesday, April 16, 2013 - 9:41 am:   Edit Post

Hide glue. I think the fretboatd is cocobolo. What do you guys think?

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