Author Topic: DS-5R Stereo - Mono (Read 1165 times)

jon_jackson · « **Reply #30 on:** February 24, 2010, 04:48:34 PM »

Jimmy and Peter, I did try just the bass/mono out (single line) to amp with 5-pin into the DS-5R initially. When that didn't work correctly (see first post) I then tried the dual patch into two inputs (simulating stereo amp). To followup Jimmy's note 157, I again tonight tried the both the single line out and double line out.

Clarifying my earlier response, when using both patch cords into two amp inputs, the neck comes only from the bass output; the bridge comes only from the treble out, when the DS-5R is in stereo mode. Leaving all connections the same, switching to mono mode results in only the bridge pickup coming through the amp via the treble DS-5R output. No sound from neck pickup.

When connecting the DS-5R to the amp only via the Bass / mono output results in only neck pickup heard when in stereo mode and only the bridge pickup heard when in mono mode.

Measuring the resistor between the stereo/mono switch and the treble out jack yields 35,000 ohms.

I'll next try measuring the resistance via the 5-pin, although I'm guessing which pin is #1 or #2. I'll assume #3 is the one in the middle...

Thanks so much for all the help. I really appreciate the support from the club, particularly Art and Thomas with the photo help. More later.
-Jon

jon_jackson · « **Reply #31 on:** February 24, 2010, 04:53:32 PM »

Duh! I just saw the pin numbers in the light. That makes it Much Easier.

jon_jackson · « **Reply #32 on:** February 24, 2010, 05:34:17 PM »

Alan:
Measuring per your first post - when the switch is in Mono and no patch cords are plugged into the 1/4 jacks, you should be able to validate this resistance by measuring from the ?Mono? out ?? jack tip to its two corresponding 5 Pin jack contacts: From Mono / Neck Out to Pin#2 [mine measured 35,000 ohms] and also from Mono / Neck Out to Pin#3 [mine measured 35,000 ohms] on the 5 pin jack [on the DS-5R].

From your second post (with the 5-pin cable connected and patch cord connected to appropriate output):
2)Connect a mono 1/4 cord to ?Mono Out? on DS-5R. Leave other end open.
3)Connect your 5 pin cable to DR-5R. Leave other end open.
4)Put DS-5R switch on ?Mono?
5)Measure resistance from tip of ?? plug to pin 3 on 5 pin connector (female end) -- mine is 35,000 ohms
6)Measure resistance from tip of ?? plug to pin 2 on 5 pin connector (female end) --mine is 0 ohms
7)If you put the DS-R5 switch in ?Stereo? mode and perform the same test you?ll see that the resistance drops to zero [mine is 16,000 ohms] when you measure from ?? plug tip to pin 2 on the 5 pin connector. If you move your ?? plug to the Treble jack on the DS-5R you?ll see the same zero resistance [again, mine is 16,000 ohms] if you use pin 3 on 5 pin connector.

So, it seems that my measurements are different than your note indicated should be present, but can you tell what that tells us? Bad 5-pin cable, something with the DS-5R, something else?
-Jon

artswork99 · « **Reply #33 on:** February 24, 2010, 06:11:26 PM »

So cool to get this kind of assistance through our community! Jon, thanks for the kind note and you're quite welcome. I think that we're close to the solution.

pacificshine · « **Reply #34 on:** February 24, 2010, 10:10:32 PM »

Jon,
Your measurements don?t seem to be consistent with your symptoms. Also, the two sets of measurements should agree, but you report different results (whether you measure inside the case or through outside cords you should get the same results). I just verified these measurements while my power supply was in the rack and the results were according to the schematic. Try to re-perform the second set of measurements and see if the results are different (they should confirm the symptoms). Also check and see that the two orange wires going to the switch are not shorted, which would explain your zero Ohm resistance in ?Mono? mode between the neck P/U wire and the mono jack (as if its summing resistor didn?t exist). Also make sure the two orange wires are connected to the bottom and center pins of the switch (hard to see from the picture). An open resistor (the one connected directly on the switch) would explain the symptoms but your measurements suggest otherwise, so the mystery continues. Let me know what you find out.
--Alan

JimmyJ · « **Reply #35 on:** February 24, 2010, 11:45:02 PM »

the plot thickens...
Jon, thanks for taking those measurements but I agree with Alan that the results are still inconclusive. I feel we're getting closer though. We're surrounding it!

The first part of your answer, testing inside the DS-5R (power disconnected please!) and resulting in the same resistance value from pin-2 and pin-3 to the mono jack in mono mode - indicates that the summing circuit is functioning correctly. As a side note, if you checked the resistance between pin-2 and pin-3 the result should be double the individual readings.

However, your second set of results, with cables, does not concur with the above and generates a few more questions...
#1: in step 6 above you say 0 ohms. Do you mean the ohmmeter swung all the way UP (to zero) or that it did not move at all (infinite ohms / open circuit)?
#2. How is the battery in your ohmmeter? If you touch the meter's two test probes together does it read 16k ohms? Here's why I ask: in the photo you posted above (via Art) we can clearly see the violet wire goes from pin-3 directly to the Treble 1/4 jack (and then continues to the corresponding jack on the rear panel). The resistor network happens after that direct connection so pin-3 to the Treble jack must be zero ohms - or the same reading as when you touch the two test probes together...
#2.5 in step 7 above you have identical readings in Stereo mode from pin-2 to the Bass / Mono 1/4 jack and from pin-3 to the Treble 1/4 jack. That indicates all is well again and we're back to our state of confusion...

So if the summing circuit is correct in part one, and stereo mode is correct in step 7, then the dang thing should all be working as advertised... It is rare for one of these switches to fail but it is possible and it may be intermittent - be sure to snap it back and forth several times while testing.

This feels strangely like doing computer tech support for my relatives, almost more difficult to explain than anything. Wish we had some kind of screen sharing so we could all remotely poke at the gear in question. Ha!

Hang in there Jon, we'll figure it out.

(Message edited by jimmyj on February 24, 2010)

jon_jackson · « **Reply #36 on:** February 25, 2010, 05:04:06 AM »

I replaced the battery and tried the tests again this morning (after 2 cups of coffee) and got different results. The battery was indeed weak. I appreciate your patience; I'm at the limit of my (non-existent) electronics knowledge. Here are the results with the new battery; I'm not sure why the difference on one measurement - probably operator error as someone mentioned.

when the switch is in Mono and no patch cords are plugged into the 1/4 jacks, you should be able to validate this resistance by measuring from the ?Mono? out ?? jack tip to its two corresponding 5 Pin jack contacts: From Mono / Neck Out to Pin#2 [ no movement - infinite ohms] and also from Mono / Neck Out to Pin#3 [ 20K ohms] on the 5 pin jack [on the DS-5R].

From your second post (with the 5-pin cable connected and patch cord connected to appropriate output):
2)Connect a mono 1/4 cord to ?Mono Out? on DS-5R. Leave other end open.
3)Connect your 5 pin cable to DR-5R. Leave other end open.
4)Put DS-5R switch on ?Mono?
5)Measure resistance from tip of ?? plug to pin 3 on 5 pin connector (female end) -- 20K ohms
6)Measure resistance from tip of ?? plug to pin 2 on 5 pin connector (female end) --mine shows no movement / infinite ohms
7)If you put the DS-R5 switch in ?Stereo? mode and perform the same test you?ll see that the resistance drops to zero [mine is now 0 ohms] when you measure from ?? plug tip to pin 2 on the 5 pin connector. If you move your ?? plug to the Treble jack on the DS-5R you?ll see the same zero resistance [ mine is 0 ohms] if you use pin 3 on 5 pin connector.

Re-measured the resistor between the switch and the treble out. It is actually 20K as expected.

Sorry for the faulty readings last night - should have checked the battery first. What a dope. It was a long day.

The orange wires seem to be connected cleanly to the switch and not touching anything else.

Maybe these will make more sense now.
-Jon

pacificshine · « **Reply #37 on:** February 25, 2010, 07:51:31 AM »

Jon,

I think you just discovered the problem. Your new set of measurements is now perfectly consistent with the symptoms. In stereo mode, there is a direct path (zero resistance) from both pickup outputs to their corresponding ?? jack outputs and in mono mode your ?Bass? (Neck) output does not make it to the Bass ?? jack and only the bridge P/U is heard. What this means is that you either have a bad (open) 20K resistor (the one with both ends hanging on the switch), a bad switch contact (but only in mono mode, still a bad switch if this is the case), or a bad connection of that resistor. It looks like the two orange wires are OK because they work perfectly when you put the switch in stereo mode and the little exposed jumper wire connecting the two pins on the switch is OK because that passes the Bridge signal to the Mono (Bass) ?? jack when the switch is on Mono.
What you need to do next to really nail this down is to measure that resistor (on the switch) and to measure the switch contact (the set of contacts where the resistor is connected) when it is placed in ?Mono?. From the middle contact to the top contact there should be zero resistance in Mono mode.

Overall, there should be a 20 K Ohm resistance between the Mono jack output and pin #2 on the 5 pin connector (and right now you have an open circuit or infinite resistance).
Keep up posted here at Ground Control. We will help you to successfully complete your mission.

--Alan

JimmyJ · « **Reply #38 on:** February 25, 2010, 08:16:35 AM »

Jon, Excellent work! Here is how to check what Alan said: With your newly powered ohmmeter (!!) touch the following points on the switch:

(That's the upper left and center right connections as viewed from the rear.) You should see 20k ohms between these two points regardless of the switch's position. If there is no reading, infinite ohms, the resistor has failed or become physically disconnected. If you do see 20k there then test the switch points here:

(Upper left to center left.) In Mono mode, switch down, these two points should be connected - zero resistance. If they are not then the switch has failed. Alembic's factory assembly work is stellar but there is always the chance of component failure. Let us know what you find and we'll work on helping you repair it. Jimmy J

jon_jackson · « **Reply #39 on:** February 25, 2010, 02:28:15 PM »

Jimmy and Alan, thanks for your help. I'll check it out when I get home tonight. Special thanks to Jimmy for correctly recognizing that I need visual aids for this. Thanks!
-Jon

jon_jackson · « **Reply #40 on:** February 25, 2010, 04:43:42 PM »

Measurement of photo 1 (upper left and center right connections) reads 20K.

Measurement of photo 2 (Upper left to center left, in Mono mode) reads no meter movement - infinite resistance.

So, does this mean it is a bad switch?
-Jon

JimmyJ · « **Reply #41 on:** February 25, 2010, 05:00:52 PM »

Yep, sounds like a bad switch. How bizarre! That also explains your symptom or bridge PU only in mono mode.
So we've found the fault, now we need to ask; can you solder or do you have a buddy that can make a couple connections for you?
Jimmy J

jon_jackson · « **Reply #42 on:** February 25, 2010, 05:28:31 PM »

Unfortunately, every time I've tried soldering in the last few years, it has resulted in a huge mess. Big lumps of solder and there is often loud screaming...

One of my bandmates may be able to do soldering. I'll have to ask him. What switch am I looking for (and where can I get it) if he believes he is competent?

I assume I could also ship it back to Alembic for re-work. I feel differently about shipping this box than I do the actual bass. It's had its one trip with UPS, and I am VERY happy it is not involved in this.

Thanks, thanks, thanks again to all who helped on this.
-Jon

mica · « **Reply #43 on:** February 25, 2010, 06:01:39 PM »

Jon, since it's be unused for many years, the lubrication in the switch has congealed. Using the switch about 100 times might make it work. If it does, it won't stick again with at least annual use. The contacts are gold, so it can't be the contacts, but if the lubricant crusts up, in can mechanically block the contact.

The switch is a DPDT type, but these are special ordered for the exact replacement. You could get a temporary switch locally (probably with a chrome bat handle) or we could send you a new switch. But we're of course happy to have you send it in here for a warranty repair which is no charge and no charge for return shipping to you.

Thomas, on yours, it's obviously not the same problem. You can elect to bring it by when you are in California (soon, right?) or send it here a head of time. Since it's under warranty, there's no charge for return shipping to you or the repair itself.

Everyone else, thanks so much for jumping in and giving excellent assistance! We can fix all the power supplies

jon_jackson · « **Reply #44 on:** February 25, 2010, 06:28:15 PM »

Mica, thanks for jumping in. I'll start the exercise routine tonight (just heard Bob Greene speak Tuesday night so I'm all ready to go), and will let you know what happens. That seems the simplest approach to start with.
-Jon