Series I Guitar Controls Log Out | Topics | Search
Moderators | Register | Edit Profile

Alembic Club » Owning an Alembic » Troubleshooting » Archive through June 11, 2010 » Series I Guitar Controls « Previous Next »

Author Message
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1484
Registered: 6-2002
Posted on Friday, May 22, 2009 - 9:51 am:   Edit Post

I'm used to the 5 position blade switch of a strat and would like the pickup switching to work in the same way.

Based on what I'm used to, the switching of pickups on my new guitar are reversed.
I would expect the pickup switching to be as follows.
1) Fully anti-clockwise = Off
Now turning clockwise one step at a time.
2) next Position = Neck only
3) next Position = Neck and Bridge
4) next position = bridge only

But new guitar is wired the opposite way round as follows.
1) Fully anti-clockwise = Off
Now turning clockwise one step at a time.
2) next Position = Bridge only
3) next Position = Neck and Bridge
4) next position = Neck only

I opened the rectangular control cavity and the pickup connectors are marked B, H, N ( I think).
If I swap the two marked B and N, would that give me the switching options I prefer, would it affect the hum cancellor, and would it be safe to do that?

Also would that also affect what signals appear at the bass and treble outputs on the psu?

(See I've just got it and considering my own custom options)
Jazzyvee
dfung60
Advanced Member
Username: dfung60

Post Number: 386
Registered: 5-2002
Posted on Friday, May 22, 2009 - 9:18 pm:   Edit Post

You're right on with your guess. The preamp for each coil is on the PC board right after the connector. Leave the hum-cancellor connected in the same place, switch the outer ones, and you should be a happy guy!

David Fung
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1486
Registered: 6-2002
Posted on Saturday, May 23, 2009 - 4:04 am:   Edit Post

Thanks Dave, does that mean the bass and treble outputs will be swapped too?

Jazzyvee
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1489
Registered: 6-2002
Posted on Saturday, May 23, 2009 - 4:57 pm:   Edit Post

Hi Dave, tried that earlier but all that changes is the pickup switching. The tone controls don't change so I get the neck pickup filter, vol and switch controlling the bridge pickup and vice versa.

Changed it all to standard and I'm back to square one.
Any more advice?
Jazzyvee
davehouck
Moderator
Username: davehouck

Post Number: 8106
Registered: 5-2002
Posted on Saturday, May 23, 2009 - 8:36 pm:   Edit Post

Loosen the knob on the pickup selector switch, turn it 180°, then tighten.
davehouck
Moderator
Username: davehouck

Post Number: 8108
Registered: 5-2002
Posted on Saturday, May 23, 2009 - 8:52 pm:   Edit Post

I just read the thread in the Showcase section (congrats again), and the knob is indeed upside down; turning it 180° should solve the problem. It's not unusual for owners to turn the knob over this way; especially on basses where the selector switch is under the neck pickup and the pointy end of the knob stabs you when you're playing slap.
terryc
Senior Member
Username: terryc

Post Number: 865
Registered: 11-2004
Posted on Monday, May 25, 2009 - 5:33 am:   Edit Post

when Mark Kind had his S2 basses built by Alembic back in 1987, he requested the selector to be placed amongst the regular controls because he had the same problem, made for a busy layout at the control section.
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 763
Registered: 8-2005
Posted on Monday, May 25, 2009 - 6:11 am:   Edit Post

so..is there any difference in sound by having the pups round "the other way"
That means...treble where bass should be and vice versa???

G
Sorry for the hijack Jazzy!!
Love the new guitar !!

George
davehouck
Moderator
Username: davehouck

Post Number: 8119
Registered: 5-2002
Posted on Monday, May 25, 2009 - 10:34 am:   Edit Post

No, there shouldn't be any difference in sound. If you switch the pickup connections on the pc card, then you may want to readjust the hum canceling trim pots.
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1494
Registered: 6-2002
Posted on Monday, May 25, 2009 - 10:52 am:   Edit Post

I've now turned the knob 180 degrees as you suggested Dave and it's pointing sharp side up and the switching is more logical now.
Thanks

Jazzyvee
dfung60
Advanced Member
Username: dfung60

Post Number: 387
Registered: 5-2002
Posted on Monday, May 25, 2009 - 3:29 pm:   Edit Post

Whoops, sorry about the wrong info! I would have to look in the cavity about doing the swap post the controls (will probably require resoldering the output connections). But it sounds like you won't need that now unless the pointy end of the selector bugs you.

David Fung
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1495
Registered: 6-2002
Posted on Monday, May 25, 2009 - 4:30 pm:   Edit Post

we shall see, it's early days yet.

Jazzyvee
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1496
Registered: 6-2002
Posted on Tuesday, May 26, 2009 - 4:29 am:   Edit Post

I'd like to get a spare Series I Cable, do you know anywhere I can buy one off the shelf?

Jazzyvee
keith_h
Senior Member
Username: keith_h

Post Number: 1287
Registered: 2-2005
Posted on Tuesday, May 26, 2009 - 4:42 am:   Edit Post

JV,
Series 1 cables are not an off the shelf item. You would either need to order one from Alembic or from one of the custom order cable makers. I know Butch Ammons at Bayou Cables will make them.

Keith
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1499
Registered: 6-2002
Posted on Tuesday, May 26, 2009 - 10:58 pm:   Edit Post

I've just contacted the UK Alembic distributor and the cable is 110 so I'm gonna see if I can find the bits to make one up myself.

Are the Neutrix 5 pin connectors the same as the Switchcraft conectors? I can't seem to find an outlet on the net from the UK that sells the original Switchcraft ones.

Any pointers?
Jazzyvee
lbpesq
Senior Member
Username: lbpesq

Post Number: 3867
Registered: 7-2004
Posted on Wednesday, May 27, 2009 - 6:34 am:   Edit Post

Jazzyvee:

You might want to check with Bayou Cables. I don't remember how much he charges, but IIRC it is reasonable. He made me a purple cord (I know it's mine and I never forget it) that has worked fine for the two years or so that I've had it.

Bill, tgo
jimmyj
Member
Username: jimmyj

Post Number: 71
Registered: 8-2008
Posted on Wednesday, May 27, 2009 - 2:06 pm:   Edit Post

JV,

Yes, Neutrik and Swichcraft 5-pin connectors are supposed to be compatible. I've changed all my cables, basses and power supplies over to Neutrik so if you're feeling particularly productive you could switch out the lot...

I'm still using some old stock of Belden 8424 I have so I don't know how it works with Canare or other wire. You need 4 conductors in a shield (screen) and the shield connects to pin-1 on both ends.

As a self-taught soldering guy I don't have any legit advice to offer but I can think of one pointer I discovered through trial and error... When soldering on either plug I would suggest inserting the "partner" at least part way to help keep the pins aligned should things get too hot. Just a habit I got into after making a cable once where the pins had moved because I had melted the nylon component holding them in place. See, I only know enough to get myself into trouble!

Also, check very carefully to be sure there was no solder overflow between adjacent pins, tolerances are tight in that small space. Best to use a continuity checker to be sure the pin numbers match up on both ends (mirror images) BEFORE you plug in the instrument.

Good luck!
Jimmy J
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1502
Registered: 6-2002
Posted on Wednesday, May 27, 2009 - 4:27 pm:   Edit Post

Thanks Jim, glad to have that confirmation about the connectors. I'm planning to make up a spare cable and probably have a go at making a smaller psu that I can carry inside my guitar case. I found a circuit on the forum somewhere and downloaded it. It seems quite a simple circuit.

I'm a bit of an old hand with a soldering Iron, I was an electrician in my much younger days.
jazzyvee
jimmyj
Member
Username: jimmyj

Post Number: 72
Registered: 8-2008
Posted on Thursday, May 28, 2009 - 10:49 am:   Edit Post

jazzyvee,

In that case pardon my elementary suggestions and please send ME some pointers!

The original DS-5 power supplies were 4.5x5x2 inches, small enough to fit the case. As you say, a simple circuit which I'm sure you could build from scratch. I have also made a few alternative supplies using pre-made +&- 15v SOLA linear supplies like this:
http://www.solaheviduty.com/products/powersupplies/scl.htm
I suspect Farnell sells them over there.

Happy soldering!
Jimmy J
811952
Senior Member
Username: 811952

Post Number: 1680
Registered: 10-2003
Posted on Thursday, May 28, 2009 - 6:27 pm:   Edit Post

My "DS-5" is kludged together from a sony camera power supply, as the original one was stolen...

John
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1530
Registered: 6-2002
Posted on Monday, June 08, 2009 - 6:17 am:   Edit Post

Ever since I got my Dragon, the PSU has been very noisy. When I plug in leads from the ouputs to my amplifier/ or two. There is a loud 50HZ mains hum. This happens whether the PSU is turned on or off, both in mono or stereo. But gets much louder when the PSU is turned on.

It gets a bit louder still when the series cable is connected to the guitar, even with the pickup switch in the off position.

However when the guitar is used on the battery and a standard jack plug to the amp, the whole thing is silent. So I think it must be something gone astray in the PSU.

I plan to open the case soon to see what is wrong. As usual, any learned advice would be helpful.

Jazzyvee
sonicus
Member
Username: sonicus

Post Number: 92
Registered: 5-2009
Posted on Monday, June 08, 2009 - 10:39 am:   Edit Post

What you are describing seems to point perhaps to a ground and/or shielding issue associated the circuits that you mention.Does this also occur when the power supply in in connection to your amplifiers with out the 5 pin cable connected? I would try all possible variable of connections again and trace and isolate the problem. I would also check the continuity of the 5 pin cable one conductor at a time .If you can substitute another 5 pin cable perhaps that. Many times filter capacitors are at fault for AC hum but it sounds like you are describing a faulty connection or shielding issue. Some times also EMF/RF problems might be worse in different locations in the same building.Other possibilities can also be improper polarity of the AC wiring . In the U.S.A. I have seen problems with HOT/NEUTRAL/GROUND miss-configurations at the power source that can lead to problems of mixed variety .
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1531
Registered: 6-2002
Posted on Monday, June 08, 2009 - 12:35 pm:   Edit Post

The problem still exists without the 5 pin cable connected. It just gets louder when the 5 pin is connected. I don't have a spare 5 pin cable to check against at the moment but I'm sourcing parts to make up my own.

I notice that the 110v mains cable that came with the PSU has 3 pins. I have changed the voltage slider switch on the back to the 230v option on the back of the unit which would be fine for the UK.

Usually we have a 3 pin plug with an earth. I've not checked the inside of the PSU to see if the earth connection is actually connected to the casing.

Thanks for your input I will try to get the back off tomorrow and have a look inside.
Jazzyvee
jimmyj
Member
Username: jimmyj

Post Number: 79
Registered: 8-2008
Posted on Monday, June 08, 2009 - 5:24 pm:   Edit Post

Jazzyvee,

How strange that the PSU is not agreeing with your amp. I presume you've tried physically moving it about? It's possible the amp it is sitting on or the rack piece it is mounted next to (if it's in a rack) is simply inducing the hum. Same holds for the short jumpers from PSU to the amp's input, make sure they are not the culprit.

Does kind of sound like an AC power disagreement though. Over here we would try a ground lift and maybe even reverse the AC polarity but at 230v I don't think you're allowed to mess with it like that.

Sometimes an "unterminated" 5-pin cable will make some noise but with the bass connected and the pickup selector in the off position it should all be dead quiet as that is essentially shorting the bass's audio outputs.

Let us know what you find. I know you know what you're doing but be careful in there, don't do this work on the roof during a lightning storm.
Jimmy J
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 788
Registered: 8-2005
Posted on Tuesday, June 09, 2009 - 3:05 am:   Edit Post

Jazzy.
I had a problem once with my DS5.
I sent it to Chris Ward at the Bass Centre in London....there's not much he doesn't know about Alembic Series instruments. He was JE's guitar guru at the time

George
georgie_boy
Senior Member
Username: georgie_boy

Post Number: 789
Registered: 8-2005
Posted on Tuesday, June 09, 2009 - 3:44 am:   Edit Post

His number is:
0207 3577703
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1534
Registered: 6-2002
Posted on Tuesday, June 09, 2009 - 11:58 pm:   Edit Post

I managed to take the back off and.... it was interesting to see all the unoccupied space in there and the few bits of wire and components. It is a really big sturdy box for such a simple device.

Anyway, I couldn't see anything amiss there no signs of overheating or dry joints.
So i just to be sure I got my soldering iron out and freshened up the the soldered joints in the AC only side of the circuit. As a result everything has has now gone significantly quieter. I've now tried the guitar with both the PSU and without and there is a minor bit of mains hum but that is probably more from the amp/cable than anything else and there is no difference between when the pickup on and off positions so that seems to be a good sign.

I will try it in my valve amp later as they seem to be less forgiving about hum.

Well I shall give it a go for a while and see how things pan out.
Thanks for your help.

Jazzyvee
sonicus
Intermediate Member
Username: sonicus

Post Number: 103
Registered: 5-2009
Posted on Wednesday, June 10, 2009 - 12:52 am:   Edit Post

Excellent . Well then perhaps you have solved the problem. ultimately instead of connections to an amplifier one could trace the audio signal path with test probes connected to an oscilloscope to find where the AC hum enters the circuit.(without an audio signal connected) One must be careful how ever and not create any dead shorts to the ac power.I would be curious about checking the internal connections to the 5 pin if the problem persists. I am happy for your success .
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1535
Registered: 6-2002
Posted on Wednesday, June 10, 2009 - 3:13 am:   Edit Post

I'm hoping it is cured but time will tell if the problem is solved or has other components to it within the circuit.
Jazzyvee
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1582
Registered: 6-2002
Posted on Tuesday, July 21, 2009 - 12:41 pm:   Edit Post

Hmm, I'm back to square one. The hum is back same as before and noticeable when using either the PSU or the jack socket on the guitar also although not as loud with just the jack socket.

HELP!!
Is this the "Way of the Dragon"?

Jazzyvee :-(
davehouck
Moderator
Username: davehouck

Post Number: 8418
Registered: 5-2002
Posted on Tuesday, July 21, 2009 - 6:59 pm:   Edit Post

In your post number 1530, when using the quarter inch jack instead of the five pin, there was no noise. So what has changed? Same amp? Same guitar cable? Same power strip? Same wall receptacle?
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1583
Registered: 6-2002
Posted on Tuesday, July 21, 2009 - 11:14 pm:   Edit Post

Hi Dave, all the items are the same so I'm a bit confused really.
I hope to have a bit of free time this weekend to try a methodical approach to this and try a few permutations with the guitar, psu and few amps to try to find out where the problem is. Generally, things are much quieter when plugged into my PJB briefcase bass combo when compared to my Laney valve guitar amp.

Fortunately I can hear the great guitar tone in spite of that so once I can find and rectify the problem all should be well.

Jazzyvee.
davehouck
Moderator
Username: davehouck

Post Number: 8420
Registered: 5-2002
Posted on Wednesday, July 22, 2009 - 5:32 am:   Edit Post

Look over the shielding inside the control cavity to make sure it looks good, that the pots and jacks are snug against the shielding, and that the cover plate shielding looks good as well. Also, I should ask, does the noise vary depending on how close you are to the amp?
dfung60
Advanced Member
Username: dfung60

Post Number: 388
Registered: 5-2002
Posted on Thursday, July 23, 2009 - 10:12 am:   Edit Post

This sounds like a grounding problem to me.

The first thing I would try is to make sure you've got the DS5 connected to AC at the same outlet as your amplifier. This means that you plug your amp and the DS5 into the same power strip or splitter, and that you don't plug the DS5 into a power strip that's plugged into another power strip.

What's going on here? When you get noise like this it may be because the ground level of the AC isn't the same at the two outlets. If there's any difference between the ground levels, then you may get some AC current "leaking" across the grounds which is the hum you hear.

The DS5 will be particularly vulnerable to differing ground levels because the outputs are unbalanced (2 conductors). It looks like a direct box, but it's just a power supply and connectors. A direct box sits in between two AC powered devices and can have this problem as well, but the balanced connector separates the signal hot, signal ground, and the shield. If you have this hum problem with a direct box, you disconnect the shield connector on one end (that's what the ground lift switch does) and the signal continues to pass on the center conductors, but the hum that was passing through the shield is interrupted. You can't have a ground lift switch with the DS5 because the unbalanced connectors combine together the signal ground and the shield - disconnect it, and you won't get any audio.

So, you need to make sure that there's no ground differential between the DS5 and your amp and the problem should go away.

Many power strips have surge protectors in them. The surge protector circuit isn't supposed to change the ground level, but I'm supposed to have a private jet and it didn't work out that way there either! In the digital world, a lot of "errors" like the surge circuit don't matter - your phone charger will work if you give it almost anything. But the DS5 lives in the analog world which literally is all black magic and it totally intolerant of "close enough".

The giveaway on this problem is that your rig hums when the DS5 is plugged in but the 5-pin jack is not connected. With no input, this must be a leaky ground problem.

If you're already on the same power strip, then the AC filtering circuit in the DS5 has a problem - either one of the big filter capacitors has gone bad or the diode bridge has failed. It's kind of funny that you mentioned about "rectifying" the problem - this is section of the circuit is known as the "rectifier" - how come I'm the only one laughing here? (ha - I know Ron just chuckled too!)

David Fung
davehouck
Moderator
Username: davehouck

Post Number: 8424
Registered: 5-2002
Posted on Thursday, July 23, 2009 - 10:41 am:   Edit Post

David; I shipped that private jet to you by UPS. If you didn't get it, then UPS must have lost it.
lmiwa
Advanced Member
Username: lmiwa

Post Number: 231
Registered: 2-2008
Posted on Thursday, July 23, 2009 - 11:00 am:   Edit Post

With that private jet arriving soon, you'll be able to fly around and diagnose all our electrical problems in person! :-)
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1587
Registered: 6-2002
Posted on Monday, July 27, 2009 - 1:55 am:   Edit Post

Ok, after ages of trying the PSU and the guitar in a variety of my amps. I've come to the conclusion that the problem may have been with the PSU in the beginning but not now.

It appears that one of my valve amps has an intermittent noise problem where even when nothing is plugged in. On Saturday, I plugged my Fender Twin amp in, powered up then left it to warm up off stand-by and I went to get a coffee then heard this enormous humming that went on for about 30 seconds or so then stopped for a while then kept coming on and off randomly.

In the quiet time I plugged the psu and Dragon guitar in and it was quiet but when the buzz came it was hugely loud.
Just for comparisson I plugged the guitar into my PJB Briefcase bass amp and my Ashdown acoustic guitar amp and all was quiet.

The laney 30w amp i use for home practice again seems to have just become noisy and plugging any cable just increases the noise regardless of a guitar being on the end or not. If a guitar is plugged in, then different guitars produce different noise levels. Strangely my strat ultra was the quietest.

This small amp has been in the boot of my car quite a few times lately when I've been doing blues jam sessions and it seemed fine on Friday when I last used it at the session but since then it's got a heavy buzz all the time.

So I think I need to get my valve amps serviced. Hope it's not expensive.

Thanks again for your input. I hope indeed this is the end of the noise problem.

Jazzyvee
davehouck
Moderator
Username: davehouck

Post Number: 8444
Registered: 5-2002
Posted on Monday, July 27, 2009 - 5:39 am:   Edit Post

Glad it's not the guitar!

Are you leaving the amp in the car overnight? If so, exposure to excessive humidity might be a factor.
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 1590
Registered: 6-2002
Posted on Monday, July 27, 2009 - 7:49 am:   Edit Post

Hi Dave, no I don't leave stuff in the car overnight more for security reasons than anything else. I'm so happy it's not the guitar, though not having a valve amp in usable condition to play it is a pain.

Jazzyvee
chalkie
Junior
Username: chalkie

Post Number: 24
Registered: 6-2009
Posted on Tuesday, July 28, 2009 - 6:28 am:   Edit Post

David,
If it helps at all you made me laugh (though not actually out loud) with your observation about the bridge rectifier. (No, nothing to do with rectifying anything about the bridge pickup). Mind you, my father told me that my first word was "2N3704"

Topics | Last Day | Last Week | Tree View | Search | Help/Instructions | Program Credits Administration