Anniversary electronic mono/stereo 1/4" jack resistor/wiring question

[lg71]

I checked my bass today, and so far the luthier as placed two 10K resistors hardwired on the tip end of each harness just before the mono/stereo switch which goes to the stereo jack. So the resistors are always connected to the tip of each harness, wether in stereo or mono.
 
1) is the value correct for the resistors?
2) is the wiring correct, or is the stereo wiring NOT supposed to have the resistor connected to the tip, like on the Series it looks like?
3) I tested the bass with a mono jack, and when I use the stereo switch the PU output (one PU output only in this scenario because it is a mono jack)is MUCH LOUDER then in mono, is this right?
 
I am suppose to got to the shop to get this checked tomorrow, I'd appreciate some help + advice.  
 
Thanks,
LG

[lg71]

Well, I am off to the shop in few minutes, I hope that what I described is how it was supposed to be, otherwise, eventually, I will  find out soon or later... Just hope that I am not going waste an other journey...
 
Thanks!
LG

[lg71]

Well, I am going to call myself unlucky then, BECAUSE I have been looking through the archives for a while, and while I didn't find answers to my questions, I saw plenty of posts with photos, part numbers, and how to go about fixing it and so on... I even saw a post two weeks ago, about someone who bought a dead harness, and managed to get everything sorted by posting photos, live with updated diagram!  
 
Well, I had to say all that, I cannot keep silent after I saw and read what I saw and read. Thanks anyway.  
 
Maybe I'll change my name, who knows...
 
(Message edited by LG71 on October 25, 2006)

[lg71]

Why can't I get any answers for this? Really, is it THAT time consuming? Or is TOP SECRET? PLEASE!
 
Is the resistor value ok for non series, or what should I use?
Should the resistors be bypassed when in stereo mode?
Should PU output be louder in stereo than mono?
 
Thanks,
LG

[cntrabssn]

LG,
 
I should open a bass to be sure, but as far as I know, those resistors should only be in the circuit when you're in mono mode, and bypassed in stereo mode. And yes, the pickup outputs will be louder in stereo. The difference is especially noticable when you run only one pickup in mono mode. I have an instrument with anniversary electronics, so I'll double-check.
 
- nate.

[mica]

Hi Louis-Gino,
 
You have a large pile of Alembic spares, so we're assuming you're using the pickup selector switch from a Series I/II/Anniversary (2-pole, 4-position). In our wiring the bass pickup is an orange wire, and the treble pickup is a violet wire.  
 
On Anniversary electronics, the orange wire from the pickup selector is in series (goes through) the resistor to one end of the SPDT mono/stereo switch. There is an orange wire from the same terminal on the switch which goes to the tip connection on the output jack. If it's like our black one, this is terminal number 4.  
 
The violet wire has a resistor connected in series and is connected to the common terminal (center) of the mono/stereo switch.  
 
Then on the third terminal of the mono/stereo switch, there is a violet wire that runs to pin 8 of the 1/4 jack (ring terminal).  
 
Wired like this, a regular set of Anniversary electronics will have a louder sound in the stereo mode than the mono mode when you are testing one pickup only with a mono cord.  
 
10K resistors are fine to use. We would use 20K at the factory, but Ron assures me that the 10K ones you have are fine.  
 
I hope this will answer your questions. If it doesn't, then I will request that you provide either a diagram of what you've wired together or a photograph or two so that we can be sure we are each talking about the same thing.

[cntrabssn]

Wow, I'm just a bit too late to correct my own error  I guess it doesn't really matter, but my bass appears to have 10k summing resistors installed.  
 
Thanks,
- nate.

[lg71]

Hi Nate,  
 
Thanks a lot for your help, it's never too late when one has good intentions. Well, the resistors + volume difference in mono/stereo mystery is now solved/clearer, and do I understand right that those resistors are always connected to the tips then, wether in mono or stereo (not just for mono)?  
You know, my wiring will be very similar to the Anniversary one, and I would love to see the inside of the real thing, to compare, to learn and to admire, as I will be doing the same to my first Arialembic when I can. I see you have a serious collection! Congrats.
 
------
 
Hi Mica,
 
Thanks for your help again, I see that you have been quite thorough and I didn't expect so much info. I know you are all busy at Alembic (and btw if you've got a vacancy, let me know, I'll leave London happily...), my questions were simpler than what you may have interpreted, most, if not everything is answered, just not 100% sure if you and Nate are saying that the resistors should be connected to the relevant tips at all time, when in mono, as well as in stereo (not just present/wired in mono)?
 
I don't think think I'll need to post photos, because I didn't do any of the wiring, I just ask the Luthier what I wanted, and while it's working, I am a perfectionist and want to make sure that it's done according to the book... I didn't expect you to go as far as wiring stuff in the photo for me, although it would have been nice, but I am realistic and understand that you have more important things to do. I am sorry to have gotten you to write so much details, it wasn't necessary and/or intentional, but certainly most appreciated.
 
Regarding the rotary switch (2 way/3 poles), I am not going to use it as simple PU selector, in fact for what I need, I require a 3 poles version (3 poles/3 or 4 positions), so the one I have becomes redundant. I have send you an important email regarding this very issue, I really hope that you can help me with it, and you are probably the only person I can ask this favor.      
My birthday is coming soon, and I hope to get the bass finished on time.
 
Thanks,
LG

[mica]

Hi Louis-Gino,  
 
I can't tell you if it's done by the book if I don't know what book I'm reading. This is why I gave to you the details about how we wire a switch for an Anniversary model. I still do not know what you have had Chris wire up for you from your collection of electronics. I certainly can't provide any opinion about how yours is wired without a diagram or photographs.  
 
I have sent you a lead by email of where you might find this special switch you need.  
 
Good luck with your project(s)!

[lg71]

Hi Mica,
 
OK, done by the Alembic book within reason I meant, with some 10/20% tolerance...
I mean, really, I thought this question was simple enough, but different people interpret/understand things different ways.  
Nate understood what I meant I think. The question about resistors values was quite straight forward, so was the one regarding differences in volume between mono and stereo modes, both you and Nate answered it clearly.  
 
The last question, I don't think requires a diagram, I mean in theory, when in mono, the two PUs are wired to those resistors (one for each PU) to sum the two signal... then in stereo, I know/think that you don't need to use those resistors, because each PU has got its on channel and they don't interfere with each other, but, my question remain the same, are the resistors being used in mono as well as in stereo, or do you get them out of the way when in stereo? BOTH option would WORK, Chris decided to have them permanently connected, I just suggested to him that we could wire things differently for stereo (he said that I should ask you!)... Would it make a difference? I don't know. What option you/Ron chose? I don't know.  
 
I very am sorry if you still don't understand what I am trying to ask, I know that sometimes it is difficult for me  explain things, and it takes huge email...
 
So once again, done by the book within reason, I meant respecting what I just said basically, which are the 3 questions at the top of this thread. For instance, you use 20K resistors (that is by the book), but you said 10K works fine (that is within reason...) Now, what if we used 1K or 300K, would it work? (that might not have been by the Alembic book...)?
 
Thanks a lot for sending me the link, I will have a look in a minute.  
 
Your help is much appreciated,
LG

[mica]

Hi Louis-Gino,
 
In the Anniversary models the resistors remain in series even in stereo. In the Series I and II models we use a double-pole double-throw switch and the resistors are removed when in stereo, so that you can connect headphones to the 1/4 inch jack (originally there was no mono/stereo switch, stero output was hard wired) because the higher power op-amps used in the Series electronics (with external power supply) could drive low impedance loads.  
 
The battery-conserving opamps in the Anniversary electronics would just distort if you connected headphones, so we don't need to get the resistors out of the way and it permits using the simpler switch and circuit.  
 
Earlier when I said, I don't know what book I'm reading I meant that I do not know what electronics you have installed in your bass now. I prefer to give specific advice about a specific set of electronics. Because if I don't have all the facts, there's a good chance the advice will not be useful.

[lg71]

Hello Mica,
 
Thanks again, those answers are plenty, I understand clearly.
 
What I use is, 2 X low pass filters, 2 X Q-switches, 2 X volumes + 1 Pan and three PUs (at the moment two Fatboys + 1 MXY) and a mono/stereo/reverse stereo switch. At present two PUs are sharing a filter and Q-swicth as well as a volume and Pan, then once I get the 3 poles switch, I will have 3 configurations so I can alternate/choose which PUs are paired to share the filter + Q-swicth, and which PU has its own filter + Q-switch.    
 
I forgot to ask you, when I asked Chris (and briefly asked you once over the phone) if there was any advantage in using 2 x 9V batteries as opposed to 1? He said, maybe if you slap hard and it distorts a lot... but he said ask Mica. He mentioned that there were two ways of doing it, 2 x 9V in parallel or 2 x 9V in series (if I remember right) that would give +9V and -9V (18V), he said that he didn't know if the circuit could accommodate the later option?