Author Topic: Series 1 bass electronics upgrade, power supply (Read 299 times)

drbottom · « **on:** July 03, 2004, 11:00:16 AM »

I recently bought a '77 Series 1 bass and have several questions.
1)The bass was pretty noisy when I got it. I emailed Mica about the hum and received the trimpot procedure. This helped a lot, but did not eliminate all the directional hum. (My home/studio is in an electrically noisy place). The upgrade is $1500 for this bass (yikes!) I'd like to hear from anyone who has had his bass upgraded. Is it really utterly quiet? For this price I would expect a perfectly quiet instrument. Are there other options?
2) What are the other 2 trimpots for?
3) The bass came without the power supply. Does anyone have one they'd like to sell? What is the experience of you who choose to just use batteries? Is there a difference in tone? Or is it just the hassle of having to change batteries and use a stereo cable from the bass?

I've wanted an Alembic for a LONG time now. Still hoping this will turn out to be my dream bass.
-Thanks

keavin · « **Reply #1 on:** July 03, 2004, 02:20:10 PM »

check the two middle trim pots,turn them a little counter/wise until theres no hum,or maybe you need some pot spray.

malthumb · « **Reply #2 on:** July 03, 2004, 03:31:01 PM »

I had 74-84 upgraded. The difference was absolutely incredible! Now, understand, that when I sent it to Alembic, it didn't have Alembic electronics in it at all, thanks to a previous owner, but when I got it back from Alembic, I was able to compare it to a 1987 Series I and a 2000 Series II that I have. The upgraded 1974 bass was quieter than either. It was dead quiet.

Peace,

James

mica · « **Reply #3 on:** July 03, 2004, 03:32:09 PM »

1) The upgrade makes the electronics even quieter than when the bass was new. Noise levels are reduced by a minimum of 40dB, typically over 50dB. It's remarkable and there is no change in the tone at all. Bad news: no appointments for this service are available until mid October. Email help@alembic.com if you want to schedule service.

2) The other trimpots are the gain for each pickup.

3) There's actually slightly more headroom with batteries, but there really isn't any difference in sound. 30-40 hours is max battery life, so unplug when not in use (the standby on the pickup selector is not off). You can also rewire the 1/4 to mono, but you will lose the ability to plug headphones directly into the bass for practicing.

Cleaning spray will not help any Alembic - this pots are sealed and do not collect dirt from the outside world. They are also self-cleaning. If the bass has been stored a long time or if you never move the controls, you'll need to excercise them by turing back and forth about 10-20 times. None of this will help with directional noise - only getting the electronics upgraded will help that.

malthumb · « **Reply #4 on:** July 03, 2004, 03:36:37 PM »

By the way, drbottom, welcome to Alembic and welcome to our crazy little club! I'm certain you'll love the experience.

There is no difference in tone when playing through batteries as opposed to playing through the power supply EXCEPT for that one time (bound to happen) when the batteries drain at a time when you hadn't planned on it. Your sound will get to be very scratchy, then it will be non-existent. If you can avoid it, DO NOT leave your 1/4 cable plugged in when you're not playing. The batteries will drain FAST.

As much as I can, I play through my DS-5 or my DS-5R. Peace of mind is a good thing.

Peace,

James

the_mule · « **Reply #5 on:** July 04, 2004, 12:36:11 AM »

Hello Philip, welcome to the club! Not so long ago I found an early 80's Series I in a pawnshop, without the power supply and stereo cable. I've enjoyed it with the batteries (Duracell) but last weekend I purchased the 'spare parts' and the bass really sounds more powerful to me (but I realise that may very well be a trick of the mind).

The problem of stereo to mono is easily solved. You take a normal instrument cable, and replace one of the mono 1/4 jacks with a 1/4 stereo jack, connecting the + wire of the cable to the ++ of the stereo jack. I didn't do this myself, but it took the local music store owner who did it for me 2 minutes, no problem at all according to him. With a modified cable like that the stereo signal from the bass is converted into a mono signal that goes into your amp.