| Author | Message | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1687 Registered: 5-2006 |
Very happy with my Series I bass, but it is a bit noisy. There’s the directional hum (when you come near an amp, I didn’t record that) and some high frequency noise (fi you can hear my wireless mouse on the recordings) You can download the recorded the noise (.wav file) here: Click here, 23 mb download Noise with all gain down: 00:04 Noise with pickup gain at 50% Bridge pickup: 00:16 Neck pickup: 00:28 Both: 00:40 Cycling through humcancelling procedure from 0 to 100% and back, then looking for the quietest position (0% on bridge pickup) Bridge pickup: 00:52 Neck pickup: 01:16 Spoiler noise for comparison: 01:56 I think there’s something wrong in the bridge pickup circuit, the pickup has been replaced somewhere in the past. The humcancelling procedure doesn’t sound the same as on the neck pickup, the hum doesn’t pass through a null; it just gets quieter when turned to zero. (most counter clockwise position) I can’t change the pickup connections on the preamp board for easy troubleshooting, because the new bridge pickup wire is soldered direct to the board (no connector) On the ¼ input it looks there’s a cut black wire, pointed out by the green arrow. Pics:    (click pictures for full size version) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1688 Registered: 5-2006 |
Did some more detective work. Looks like all the wires that should connect to the 1/4 output are there. It looks like the bridge pickup is wired wrong:  | ||
| pierreyves
Senior Member Username: pierreyves Post Number: 1223 Registered: 11-2006 |
Flip, for what are you waiting for ? HERE ? | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1690 Registered: 5-2006 |
Can you fix it for me? :-) I changed the pickup wire and the hum cancelling procedure works the same now as on the neck pickup. (with the same results as you can hear on the neck pickup) Counterclockwise there's high frequency stuff going on, clockwise there's the low pitched hum. | ||
| terryc
Senior Member Username: terryc Post Number: 2364 Registered: 11-2004 |
Would it not be a better choice to let Ron Wickersham work his magic on it, in the long term it would be worth it! | ||
| sonicus
Senior Member Username: sonicus Post Number: 4130 Registered: 5-2009 |
Perhaps it might be prudent to insure the power source is clean as well and therefore a look at or replacement of the filter capacitors in the power supply . Just thinking ___ . | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1692 Registered: 5-2006 |
fwiw: Noise is the same through the 1/4 jack powered with batteries... (though it's wired stereo, so I can only check the neck pickup) | ||
| mica
Moderator Username: mica Post Number: 8504 Registered: 6-2000 |
Have you made any changes since you made the recording? | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1693 Registered: 5-2006 |
Only soldered the bridge pickup correctly (I think, reverse of the above picture) | ||
| mica
Moderator Username: mica Post Number: 8505 Registered: 6-2000 |
So there was no change after resoldering? | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1694 Registered: 5-2006 |
Sounds like it got a bit better, this is with both gains at approx. 50 % and all controls open/max Q. Bridge pickup, both and neck pickup: 6 mb Wav download (Message edited by fc_spoiler on May 02, 2015) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1695 Registered: 5-2006 |
.... and the hum cancelling procedure now works as it should on the bridge pickup. Though there is no real quiet position, there is a quieter position somewhere in the middle but the noise from the most counterclockwise and most clockwise position are overlapping. (same on both pickups as you can hear in the first recording of the procedure on the neck pickup) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1696 Registered: 5-2006 |
The high frequency noise (the beeps) is coming from my laptop, if I turn the bass towards the laptop it gets louder. | ||
| jimmyj
Senior Member Username: jimmyj Post Number: 570 Registered: 8-2008 |
Hey Flip, You've definitely solved the MAJOR problem of the bridge pickup being wired backwards. The way it was caused the noise reduction circuitry to act as a noise PRODUCTION circuit and simply add more noise as you turned up the trimpot. Listening to your latest wav file, I think you are now within spec - for a '79 without Ron's latest mods. We benefit from these big open-sounding single-coil pickups which hear not only the string moving in the magnetic field but also any broadcast hum or noise within feet, or the neighbor's copy machine, or the radio station down the block... Thats the nature of amplifying the output of a coil of wire. Humbucking pickups usually try to fix this by putting a 2nd coil either next to or under the pickup coil and wiring the two out of phase to each other. But my understanding is, when the 2nd coil is within the pickup's magnetic field it will inevitably "hear" the string and do something "unmusical" to the tone. Alembic's very clever solution was to move the hum canceling coil away from the pickup - and also for both pickups to share it. The downside is, since it's physically an inch or two away it hears noise and hum in a slightly different time and thus can't cancel it out 100%. Having played Series basses since the mid-70's, I was well aware of the need to find "the quiet spot". Though sometimes a nuisance (and man, even some studios were impossible) I found it worth dealing with because of the great tone. Now Ron has found additional magical individual tweaks which can considerably lower the noise floor on these instruments. This has almost eliminated the issue for me but there are still some instances when I need find the quiet direction and keep the neck pointing that way. Remember that if you crank up the Q you are adding a large boost to the high frequencies which will also include a lot of the inherent noise. That's a fine looking bass with its original "flat-pack" circuit board and it sounds nice in your samples. Enjoy it and play the heck out of it immediately! Jimmy J (Message edited by jimmyj on May 02, 2015) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1697 Registered: 5-2006 |
Thanx Jimmy! I'm a bit spoiled with the ultra quiet activator equipped basses, tone of the Series can't be beat though. :-) I think you're right about being within spec, if I turn away from the laptop I can get it almost 100% quiet :-) (on the recordings the distance between laptop and bass is about 3 feet) I also found this: http://alembic.com/club/messages/394/44491.html I'm going to get a couple of resistors next week (for the mono 1/4 mod) so I might as well give this a try. Mica: The 15Kohm resistor must be placed between the shield and signal cable of each pickup? And is there a way to test the matching of the pickups myself? Might also be an option to order a complete new pickup set (incl dhc would be best I think?) but I first need to recover financially from this purchase... | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1698 Registered: 5-2006 |
And Jimmy: I am enjoying the heck out of it, this baby is hard to put down. Extremely inspirational and I'm sure it's going to make me a better bass player. :-) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1699 Registered: 5-2006 |
Working on my post number count :-) Mica: For refurbishing the DS-5: I found RAL 5024 to be closest, would that be the right color? (Message edited by fc_spoiler on May 03, 2015) | ||
| mtjam
Advanced Member Username: mtjam Post Number: 303 Registered: 11-2011 |
Your Series sounds great! Can't wait to hear more from you rockin' out live with it! Enjoy! | ||
| bob2
Junior Username: bob2 Post Number: 45 Registered: 2-2009 |
flip, I don't know if your instrument has had "The Upgrade", but here is the FAQ thread, just in case you have not seen it yet: http://alembic.com/club/messages/16271/16310.html?1107541986 | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1701 Registered: 5-2006 |
Thanx both! No upgrade on this bass (I've asked Mica before purchase) only downgrades... First thing I removed (before both recordings) was a ground wire that was attached to the bridge and ground lug of the 5 pin output (not even soldered, wire was twisted around bridge/lug...) Also the powersupply had some poorly done mods... | ||
| terryc
Senior Member Username: terryc Post Number: 2366 Registered: 11-2004 |
In the 17 years I have owned my MK Signature I have never heard any erroneous noise coming from my bass at all, okay if I put directly close to an EM source(a TV) it certainly buzzes but under all the conditions I have played under I have never heard EM interference, those humcancellers really are the biz! | ||
| enzo
Senior Member Username: enzo Post Number: 476 Registered: 4-2009 |
Very interesting thread Flip, thanks for uploading those samples, they kind of match what I was hearing on my SII, at least from what I can judge thru my computer speakers. My bass is now at the factory waiting to be tested by Ron, hopefully he can reduce the hum working on the same set of pickups or maybe even find part of the problem in the accessories (DS5 and cable). Looks like it will be getting also a full respray! I bought some Yoga DVDs to help with the waiting. | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1704 Registered: 5-2006 |
OK, done some more detective work... Looks like one of the signals is out of phase... (is that even possible?) I've recorded the bass and treble out direct into a Roland VS recorder, each pickup on a seperate track with all controls (and Q) at 100% 24 MB wav file download 00:00 Sound as is 00:28 Phase reverse on bridge pickup channel 00:57 Phase reverse on bridge pickup channel, neck pickup gradually turned down 01:23 Phase reverse on bridge pickup channel, bridge pickup gradually turned down 01:50 Phase reverse on bridge pickup channel with chorus and reverb on treble channel, for fun :-) Did you see my mails Mica? (Message edited by fc_spoiler on May 09, 2015) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1705 Registered: 5-2006 |
Also found that one of the flatpacks legs was bend and most likely shorting out to the leg next to it:  | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1706 Registered: 5-2006 |
Looks like one of these fellas is installed backwards, could that be the reason for the signal being out of phase?   | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1707 Registered: 5-2006 |
Note the reversed phase setting is also much quieter... | ||
| jimmyj
Senior Member Username: jimmyj Post Number: 571 Registered: 8-2008 |
Hey Flip, Yeah, I like the last version with the effects. Ha! OK, a couple things regarding your questions about the components mounted on the board... Last one first: Pay no attention to the printing on the FET, that does not indicate which pins are which. If it were installed incorrectly you would have no signal whatsoever coming from the bridge pickup. Likewise for the bent leg of the flatpack opamp in post 1705. While you certainly don't want those to touch each other - if they were shorting then your hum balance circuit would not be functional at all. The only possible "fault" you have discovered is the way the replacement pickup was soldered to the board (in post 1688). It looks like it was done professionally - as in, proper use of a wire-tie for strain-relief. And the way the board is laid out it would actually be a difficult mistake to make as the shield peels off first and the center wire connects logically 1/4" further. But since that pickup is obviously the only part that is non-original, this is the only logical fault that could be present. Follow my logic? If you can confirm that this pickup is wired incorrectly, then you'd have something you could fix to bring it back to spec. (Can you take a better photo for us of just that spot? With better lighting? That might help us figure it out.) Now a word about "phase" or polarity... When comparing one pickup to the other you will find that there is no exact "in-phase". You can usually hear some change in the low end but the two pickups will never completely cancel each other out if thrown out-of-phase. That's because the pickups "hear" the string at different physical locations so the waveform is in different "phases" already. I think some guitars have out-of-phase as a switch choice right on the axe, no? So this is part of the beauty of the Series stereo output - you can experiment with separate tone controls, effects, and phase of the individual pickups externally. You may decide you like it when the pickups are out-of-phase for soloing and in-phase for playing bass lines. Anything goes. The only "right" is the one you like the most. Enjoy! Jimmy J | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1708 Registered: 5-2006 |
Follow the logic totally, thanx! :-) I think there's a way to see what the polarity of a pickup is, With a multimeter you should read either + or - when you put a signal through the pickup? The signal (inner) wire was definately attached to the same strip where the other shielded wires were connected, so if the phase can't be reversed in the circuit the pickups must be out of phase I guess... I just got in contact with the original owner, according to him it always had noise related problems and the pickup was replaced soon after he got it (old pickup was dead) He got the bass in 1984 and it has been serviced many times. Btw: When I got the bass I noticed was a ground wire attached to the bridge, in the cavity it was attached to the ground lug of the xlr output... Here are some better pics:    (Click pics for full size version) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1709 Registered: 5-2006 |
Also some positive notes :-) This bass is absolutely stunning, plays like a dream and looks like she’s left the mothership yesterday. There are only some dings in two spots, the rest looks brand new/showroom shine. The side of the fingerboard is also under the finish, haven’t seen that on an Alembic before… Frets, inlays and fingerboard also looks brand new, she has either seen very little action or must have been refinished. (Haven’t asked the original owner yet, but I doubt it was refinished) Weight was a surprise for me, I was expecting a heavy monster but she is about the same weight as my 5 string basses. :-) (thanx for that also JJ! Like the low B a lot!) :-) I also noted how well you can hear the effect of the chambered body when played unplugged, I’m pretty sure that also adds to the “hugeness” of the amplified sound. When the “phase” problem is solved, I can move over to the next phase. :-) I plan on upgrading the electronics to Series II, I do miss the master volume control a bit… The pickup selector will stay in place, so it will be a classic 70’s/early 80’s SII layout. :-) Here’s a recording I did with all controls at 100% (also the pickup gains (!)), each pickup on separate tracks. Bridge pickup channel with phase reversed and chorus + reverb, no eq/etc on both tracks (just the direct signal from the DS5) Tune is Jason Newsteds “My friend of misery”: 15 Mb download I love this bass! :-) | ||
| mica
Moderator Username: mica Post Number: 8510 Registered: 6-2000 |
Just hold a compass above the pickup to see if north is up or down - then see if the other pickup matches. There are both types of pickups out there, and since you've got them from 2 different vintages, it's certainly a possibility. I sent you a reply a moment ago. I was out sick most of last week and didn't open my emails all weekend. Gotta love those little 7-year old disease vectors. | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 4494 Registered: 6-2002 |
Sounds great FC | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1710 Registered: 5-2006 |
Thanx! I shall see if I can find a compass... If they're different the only remedy is a new pickup? And if so, would there it be beneficial to order a complete matched set? (could you send me a quote?) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1711 Registered: 5-2006 |
And good to hear you're feeling better Mica, stay healthy! :-) | ||
| sonicus
Senior Member Username: sonicus Post Number: 4148 Registered: 5-2009 |
Flip, Congratulations , AND I share your enthusiasm of your new baby as mine is in the process of improvements as well (73-32) With your excellent driven tenacity you have really made quite an improvement. I really like your "My friend of misery” as well . I have been working on a "claw hammer " bass technique for a similar sound as well . Mica , I am glad that you feel better too ! Wolf (Message edited by sonicus on May 11, 2015) | ||
| jimmyj
Senior Member Username: jimmyj Post Number: 572 Registered: 8-2008 |
Hey Flip, A couple more comments and I'll stop because it seems you are obsessing over things that aren't actually broken. :-) Or maybe it's just a way to get us all to listen to your demos. HA! (I am teasing now, really.) First, it looks to me like the pickup is wired correctly. It would be hard to do it backwards because the shield peels off and then the center conductor continues 1/4" further onto the board... (See the pic of your pic below). There does seem to be a repair to the 22M-ohm resistor which may have accidentally been lost during the pickup replacement job. And, the solder work on the underside of the board looks a bit ... stone-age. No offense if the service guy happens to read this thread - it is all working! But what Mica said above means it's still possible your two pickups are out of phase to each other and I can't wait to see what you discover. (You don't need to get the compass very close as the pickup magnets are quite strong. Just see which end of the needle points towards the bass for each pickup. If one is "North" and one is "South" you have a mismatch. Cool test!) Next, the "ground wire to the bridge" is something somebody probably did in a misguided effort to reduce hum - which more than likely was just coming from the pickups. I think this is a common Fender bass thing but doesn't apply to these basses - or it would have been part of the original circuit. The gang here can correct me if I'm wrong about that one. Penultimately, you have an old style preamp board with the old style in-line coaxial pickup connectors. The current pickup connectors have the male part mounted directly to the board. There are adaptors available so you can use old pickups with a new board (and maybe vise versa) but since your replacement pickup has been hard wired your rig has already been "altered". If you were to order a new set of pickups, how would you connect them? If you got a new board AND pickups, you would still need an adaptor for the hum coil which has the mini coax. And so... Lastly, If you are planning to send this bass to Alembic to update the electronics package then all of this is moot. Until you do that, flip the phase externally (if that sounds better to you) and just play the thing!! The bass sounds great in all your examples! Jimmy J  | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1712 Registered: 5-2006 |
Hah! Definitely a cunning plan to plug my demos! :-) I'm pretty sure it is "broken" though... It might not be that obvious if you listen through speakers, but I'm sure you'll hear it with headphones in the example from post 1704. That "out of phase" sound (00:00 Sound as is) is the sound coming from the mono out of the power supply. When played through my rig or the SWR combo, all lows are gone and its really harsh sounding with lots of noise... When you turn down the filter (with Q on full) it gets real nasty, no nice "musical" sounds to be found... With the stereo outs used and the phase reversed on one channel (like on the rest of the recordings) the lows are back and there's much less noise. I'm pretty sure that's what the Wickershams had in mind when this baby was born :-) If I would order a new pickup (or complete set) I would ask for the new connector type + short wire with the other side of that connector attached. (70's style with new style connector(s)) The blob on the resistor you point out with (repair) is where the shield of the pickup was attached (as you can see in the pic of the first post) When she's well again, I'll clean things up :-) Bonus content: The refurbished DS5:     ("before" pictures can be seen in the showcase here) | ||
| sonicus
Senior Member Username: sonicus Post Number: 4153 Registered: 5-2009 |
Nice work ! | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1713 Registered: 5-2006 |
Thanx! The mighty compass has spoken: Youtube link (red is north, white is south) | ||
| jimmyj
Senior Member Username: jimmyj Post Number: 573 Registered: 8-2008 |
Flip! I know I said I'd stop but I seem to keep going, sorry! And the more I say the deeper a hole I dig for myself. (Sorry about the solder job comment...) OK, NOW I am understanding - you have already flipped the bridge pickup where it's soldered to the board. That's why in your latest pic it looks correct - because you fixed that! Got it. Hard to see in the first post but now I see the different colored wire-tie and with your explanation of the solder blob on the resistor leg... it's all making sense now. Your compass video seems to indicate what Mica was hinting at above - that we have a mismatched pair of pickups. But I would do the test in a slightly different way.. Try standing the bass up in a stand, then bring the compass in from directly in front of each pickup and see which side of the needle points toward the bass. In other words, the pickup's coil is wrapped around the magnet which is rectangular in shape and shorter than it is wide. But the magnet's North or South poles should be facing out the front and out the back of the bass, perpendicular to the strings. (Here I go again, probably wrong about this too). My current theory (which is mine!) is that your two pickups are indeed a mismatch. Furthermore (a-hem) I think a previous tech, or perhaps whoever installed the pickup, already went through these steps and that's why it was wired backwards to the board when you got it. Now the tricky bit, and we'll need to hear from Mica on this: If the magnet is reversed in your bridge pickup, does that also mean the windings are reversed and does that mean the hum canceling circuit would not function??? I bet that's true. This could explain the whole mystery! You are VERY CLOSE to figuring this out. Great detective work and well worth getting this bass back to spec. Nice work on the DS5 too. Maybe not done after all... Jimmy J (Message edited by jimmyj on May 12, 2015) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1714 Registered: 5-2006 |
And some more bonus content: A friend (jeweler) made a silver script for my birthday :-)  I like the looks of logo + script better than just the logo and it makes it a bit easier to explain if someone asks what kind of bass it is :-) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1715 Registered: 5-2006 |
No worries JJ, I appreciate any input highly! Latest pic is indeed my handywork, looks worse in the picture than irl...   With the phase reversed on one channel, everything (incl the hum canceling qualities) seems to work great (as you would expect from these tone monsters) I think they indeed noticed the pickup was "out of phase" and just rewired it backwards, with that wiring the tone was ok but with lots of noise... That's also most likely the reason I have an almost brand new '79 bass here :-) If the original owner or repairguy had figured this out, the bass would most likely be played a lot... (have I already said this is a great bass?) :-) The compass seems to work in any position, there's always one pole attracted to the pickup. I also checked with my other basses, they all attract the red end :-) (the old '79 pickup attracts the white end) Pretty sure this baby will be up and running at 100% capacity soon, thanx all! :-) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1723 Registered: 5-2006 |
Had a blast with this baby last night, I think this will be my favorite bass ever soon :-) Can't wait to use this bass with the 'tallica tribute, though it doesn't quite have the looks it sounds exactly like Newsteds basses. (a little less bright, most likely because of the woods or the extra boost of the SII electronics) Main basses for the tribute will always be the Elan 5 and Spoilers, but I will take this bass for backup and for some special gigs. :-) The Series I will be my main bass with my other band, together with her Walnut fretless sister. Fun to see the (almost) most expensive Alembic pair so well with one of the least expensive ones :-) Did you see my mail Mica? Plz include a pointer knob in my package (if possible) even if I find it, it never hurts to have one in stock :-) (I lost the pickup selector of my '83 Spoiler at a gig this weekend, apparently I didn't tighten the screws enough after cleaning my baby...) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1725 Registered: 5-2006 |
Mica?  | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1729 Registered: 5-2006 |
I might have found a pickup, will know for sure later this week and might also be able to score some Series II conversion material :-) Also did the "mono output mod", but would want to replace the resistors with the ones Alembic uses. (took the resistors from an old vcr board) And I can confirm the pointer knob of the Spoiler is mia, must have lost it onstage... :-( Also I'm going to need a new backplate for my '83 Spoiler and a bunch of threaded inserts + screws (incl the "tool" screw) There's also one threaded insert missing in the Series I, the Spoiler came with broken backplate and all inserts missing... But I think I'll save that for my next order, could maybe be combined with the requested woodcards. :-) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1742 Registered: 5-2006 |
New pickup is on order :-) I decided to play safe and order a new one from Alembic. First 3 decades of Alembic:  '79 Series I, '99 Orion and '88 Spoiler | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1743 Registered: 5-2006 |
With the SWR combo (Bassic Black) and Roland VS2000CD hookup:  | ||
| edwardofhuncote
Advanced Member Username: edwardofhuncote Post Number: 384 Registered: 6-2014 |
That's quite a trio FC! Even with twenty-some-odd years between them, and totally different patterns, you can still plainly see the similarity. | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1745 Registered: 5-2006 |
Thanxs! Damn right, they do show where they came from :-) Mica: Did you see my mail with the order for the pickup? Seems my manager is also not getting all mails I send out... | ||
| mica
Moderator Username: mica Post Number: 8547 Registered: 6-2000 |
I did, but I thought you wanted to wait until the sage shirts were in, did I get it wrong? | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1746 Registered: 5-2006 |
Nope, perfect! Thanx! :-) But haven't received the proforma yet ;-) | ||
| fc_spoiler
Senior Member Username: fc_spoiler Post Number: 1817 Registered: 5-2006 |
Case closed, new pickup installed and quiet operation with full sonic attack! :-) | ||
| jazzyvee
Senior Member Username: jazzyvee Post Number: 4747 Registered: 6-2002 |
Great news. |
