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fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1862
Registered: 5-2006
Posted on Tuesday, February 16, 2016 - 5:39 pm:   Edit Post

Hi all! :-)

Note: I am crazy enough to fool around with this stuff.
If you are not experienced and don't know how much a high voltage jolt can hurt or even be deadly DON'T TRY TO DO THIS YOURSELF!

Ive tried to make my DS-5 a little more versatile, also plan on doing this to a Rack power supply once I get my hands on one of those. (for the big Mesa rig)

In one of the songs of my new band I use two basses simultaneously, I hit the low B on the fretless 5 (while its on a stand) as accent of the B I play on the Series I

You can hear it in this recording (again shameless spam) :-) (and live I dont do the slide to A on the fretless, that would require at least the mythological third arm) :-)

YouTube link

My DS-5 allready had a huge hole in the back, so heres what I did:
I installed a female mono jack in the back and connected the tip of this jack to the tip of the Bass/Mono out (with a 20K resistor, see pics)

When used mono, it works :-)
But when used Stereo it doesnt :-( I only hear the Series I, not the fretless

Btw, my stereo rig is not very impressive, for the bass channel I use a SWR Bassic Black and for the treble channel an active 12 inch Laney floor monitor.
So for now I dont want the fretless over the treble channel, Im pretty sure the low B and bass control of the Orion will destroy that poor floor monitor.

So here are the pics, hope its all clear enough and hopefully someone will spot my mistake :-)
Oh, and the last picture shows off one of the nice thingies I got in my latest package from Santa Rosa, thanx Mica & crew!









(Message edited by fc_spoiler on February 16, 2016)
edwin
Senior Member
Username: edwin

Post Number: 2200
Registered: 5-2002
Posted on Wednesday, February 17, 2016 - 12:25 am:   Edit Post

I'm not sure I follow what you did in there. Are you trying to run two basses from one power supply and have a stereo output?

It looks like a lot of wire running around in a small space.
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1864
Registered: 5-2006
Posted on Wednesday, February 17, 2016 - 7:41 am:   Edit Post

Two scenarios:

*For using the Series bass with any other (non series) bass (in my case the Orion 5) without having to plug/unplug all the time and be able to play both basses simultaneously.
I used a Roland VS recorders mixer section for this previously, but thats unpractical to set up, takes up extra space and adds some noise

The input on the back is fed straight to the Bass output, no connection to the power section there.

*In the big rig (with rack ps) Ill be able to play wired for rehearsals and plug in the wireless in the input for live gigs. So theres a minimal amount of switching between the live and rehearsal setup.
When I play the Series I with a wireless system, I use the two internal batteries (for now, plan on making a portable accu powered ps asap)


And yeah This PS has seen some rough times (unlike the bass) It was modified with a horrible and dangerous looking on/off switch. Most likely more has been done but all works as expected :-) (not counting in my mod)
jimmyj
Senior Member
Username: jimmyj

Post Number: 625
Registered: 8-2008
Posted on Wednesday, February 17, 2016 - 10:06 am:   Edit Post

Hey Flip,

That is one well used DS-5! A couple of mine look like this too...

It works in mono because you've essentially built a resistor summing network where the Series bridge pu, neck pu, and the output of your fretless - are all 20k away from that front panel mono bass output on the DS-5. With active basses that's a great way to do it!

To make it work in stereo will be trickier because the Series outputs no longer have those resistors in line. And simply running two 20k resistors to the new rear panel jack would make that a mono "output" jack, which your fretless probably wouldn't like...

Possibly moving the 20k Series summing resistors to before the mono switch, and then two 20k resistors from the "input" jack to both front "output" jacks... But I'm not sure how that would effect the level of the fretless into your stereo rig... Plus, if you then switched to mono you'd only have 10k from the rear jack to the output...

As you can see, I only know enough about this to get myself into trouble. HA!! Best wait for wiser suggestions...

Jimmy J
ed_zeppelin
Advanced Member
Username: ed_zeppelin

Post Number: 258
Registered: 2-2010
Posted on Wednesday, February 17, 2016 - 10:11 am:   Edit Post


quote:

Btw, my stereo rig is not very impressive, for the bass channel I use a SWR Bassic Black and for the treble channel an active 12 inch Laney floor monitor.




Stanley Clarke uses a similar setup, where instead of left/right it's high/low. (He also thinks of his stage rig as a monitor, and relies on the FOH soundman for his "sound." I only mention it because it's a much-discussed point of contention on this forum.)

Bear in mind that he's also running his string bass A/B through the same rig incorporating two F-1X preamps, a Fender Champ and a bunch of EBS MicroBass DIs and other toys.

I mention it for comparative purposes, and also because I use the same basic setup (I play upright primarily and sort of plugged the Alembic into the system I had set up for that, rather than the other way around.) Running piezo transducers and a soundhole-mounted condenser mic in true stereo is a nightmare and sounds like crap, so I run it high/low through two amps, and discovered the Alembic sounds great that way, too.

I was quite pleased to discover that Stanley arrived at the same conclusions, despite the fact that he never consulted with me whatsoever :-)

By the way, here's my "DS-5," which I made from Radio Shack parts decades ago. Mica took pity on me and sent me the schematics. What a great company, huh?



It was supposed to be a temporary solution until I could afford a real DS-5, but once I beat the hell out of an old bottom plate from a DOD stomp-box, covered it in copper foil and mounted it in there to isolate the jacks from the old Rock-ola jukebox step-down transformer, it's dead silent and works just spiffy (my excuse for why I keep buying crap instead of a proper DS-5, to be honest). Plus, I'm rather fond of the Star Trek lunchbox.

I applaud your initiative and craftsmanship.
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1865
Registered: 5-2006
Posted on Wednesday, February 17, 2016 - 5:41 pm:   Edit Post

Thanx (again) Jimmy!
I think you're on to something there, this might work for me:
Replace the neck pickup 20K with a wire and place the 20K before the switch (directly after 2 from neck pickup)

In mono mode the three signals are all summed through the 20K resistors.

In Stereo mode the bridge pickup goes straight to the bridge out (treble), the neck pickup and input are summed trough the 20K resistors.



Pretty sure Ive missed something here, I know much less so thats a recipe for some serious trouble :-)
When experimenting I plug in each component in a row, when something is not working as expected I immediately unplug that component.
would make that a mono "output" jack, which your fretless probably wouldn't like... Did scare me a bit though, I shall take a bit more care next time.(and wait for the green light from the experts here)
So, thanx again (again) Jimmy. Great to have you and your knowledge here! And no worries, the Orion is fine! :-)

Thanx Mr. Zeppelin! :-)

Thats a tidy powersupply!
Maybe I have to tidy things up a bit in mine, strangely enough it is dead quiet in this state. A bit frustrating to see compared to the big rig with all its perfect wiring (quality cables, all Neutrik connectors) central power supply etc, that beast is a pain ********* to get quiet :-)

Big Rig:





This set will only be used in Mono mode, the Strategy gets its signal from the Slave out of the Bass 400.

The Ibanez HD1000 is replaced with a HD1500, the Alesis with a Lexicon MX400 and the wireless is in a separate rack now.
On the pedal drawer theres a Big Muff, Little Big Muff and Tech21 XXL distortion, on the pedalboard a Mesa Abacus midi switcher, Morley PWF, Classic Wah and a Midi controllable A/B switcher to switch between the Morleys (G Lab midi 2) and a Boss CS-1 (only used with the PWF)

The Bass 400 powers two 1x15 Diesel cabs, the Strategy two 2x10 Diesel cabs (all EVM speakers)
elwoodblue
Senior Member
Username: elwoodblue

Post Number: 1828
Registered: 6-2002
Posted on Wednesday, February 17, 2016 - 6:21 pm:   Edit Post

I'm getting smarter just hanging around here, slowly ;)

Nice Rig FC!
I love those Ibanez HD units.I use the MX400's in my racks also,they're great!
terryc
Senior Member
Username: terryc

Post Number: 2460
Registered: 11-2004
Posted on Monday, February 22, 2016 - 9:18 am:   Edit Post

All too complicated is my opinion but hey, what do I know !
flpete1uw
Senior Member
Username: flpete1uw

Post Number: 611
Registered: 11-2011
Posted on Monday, February 22, 2016 - 11:42 am:   Edit Post

Hey Flip,
I just changed out the caps on my F2-B they were 1/3 the size of the originals. Newer Caps have the same values using much less space. Could save a you some valuable real-estate. Just a thought?
Pete
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 4916
Registered: 6-2002
Posted on Monday, February 22, 2016 - 12:57 pm:   Edit Post

Hi Flip, I'm just wondering do you have roadies or good friends to help you carry that gear up and down stairs when you are doing gigs?
Those two mesa boogie amps alone must pack some serious kilograms
jazzyvee
Senior Member
Username: jazzyvee

Post Number: 4917
Registered: 6-2002
Posted on Monday, February 22, 2016 - 1:28 pm:   Edit Post

Hi Flip, I'm just wondering do you have roadies or good friends to help you carry that gear up and down stairs when you are doing gigs?
Those two mesa boogie amps alone must pack some serious kilograms
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1868
Registered: 5-2006
Posted on Monday, February 22, 2016 - 2:07 pm:   Edit Post

Hah! :-)

We do have some guys that sometimes come with our gigs, but most of the times we have to load/unload/etc ourselves :-(

The Bass 400 is a bout 24Kg, the Strategy 27Kg and the rack 30Kg, so that's pretty heavy. Thank god for the wheels, but stairs are always very uncomfortable... (also the tiny stairs to a stage, I love ramps!)

The drummers hardware case is the worst we have to haul... I hate that thing! :-)


I've been asked if I want to be basstech for Jerry Only (Misfits) So maybe I'll be a roady this Summer. :-)
If I get the job, I'll try to sneak in some Activators in the Devastator Basses :-)

Pete: Thanx! I've been thinking about replacing those caps, will indeed save a lot of space.

Btw, cleaned things up a bit:

keith_h
Senior Member
Username: keith_h

Post Number: 2370
Registered: 2-2005
Posted on Monday, February 22, 2016 - 2:33 pm:   Edit Post

"We do have some guys that sometimes come with our gigs, but most of the times we have to load/unload/etc ourselves :-( "

Ah yes the strong back of youth however in my day we didn't need no stinking wheels. :-)

Keith
edwin
Senior Member
Username: edwin

Post Number: 2208
Registered: 5-2002
Posted on Monday, February 22, 2016 - 2:52 pm:   Edit Post

Looks much better! I suddenly feel much more tranquil.
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1870
Registered: 5-2006
Posted on Thursday, March 03, 2016 - 2:39 pm:   Edit Post

Glad to report the mod is working perfectly, Thanx Jimmy! :-)
No noise and the sonic spectrum seems to be evenly divided between the two basses :-)

Looks like this in my DS5:







Also replaced the red led with a green one:



The extra 1/4 mono input:



For the rack powersupply I plan on adding two inputs, one in front and one in the back.
The wireless system plugs into the back input and the front input(s) can be used at rehearsals or as emergency input if the wireless fails during a gig.

Heres a current pic of the effects rack:



One empty space left, waiting for the DS5R/DS 6 :-)

Cozy corner:

jimmyj
Senior Member
Username: jimmyj

Post Number: 629
Registered: 8-2008
Posted on Thursday, March 03, 2016 - 11:00 pm:   Edit Post

Hey Flip,

You've cleaned up your DS-5 nicely but I'm not sure I've led you down the right electrical pathway... (Remember, I don't really know what I'm talking about!)

To correctly operate in mono there should be THREE 20k resistors involved. (Is there one more that we can't see wired into the jack/switch?) You want one from your new input, one from pin 2 of the 5-pin connector and one from pin 3. The other end of these resistors should then meet at the mono output jack.

In other words, as long as all three preamp outputs (your Series has two outputs, your Orion has one) are 20k away from your summed mono output, then they should all be happy. If you shut off the Series bass, which essentially shorts the outputs, the Orion bass shouldn't be effected.

If there are only 2 resistors in your circuit I would think one of your Series outputs would appear suddenly louder than the other.

Furthermore, I'm not sure this wiring is going to work in stereo. Although if I'm reading correctly, you only ever want the Orion to appear on that bass output jack, even if the Series is running in stereo? If that's case you've almost got it, but may still need one more resistor to make the levels all match.

If you wanted your newly added inputs to appear at both stereo outputs, that's a bit trickier. I understand the concept of summing signals to mono - as I've been trying to describe - but splitting a mono signal to two outputs is a bit more complicated as far as resistor values, loading, etc... I'd need to do some experimenting to see what worked.

At one time I had a rack piece I called the "sum-thing" which only did resistive summing. Signals A+B from the bass were summed with the output of a stereo chorus (effect only when turned on). Those two outputs drove the stereo power amp and speaker rig, and they were summed again to make a mono signal for the DI out. Basically 4 to 2 to 1. And to my surprise, it worked. Ha!

You're wireless rig's output is also an "active" signal so that can be summed in the same way you're thinking, at least to mono... Just watch out for added noise.

Hope I didn't make you do any unnecessary soldering!

Jimmy J
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1871
Registered: 5-2006
Posted on Friday, March 04, 2016 - 12:42 am:   Edit Post

Thanx again :-)

No worries, there are three resistors. The third is on one of the switches on the Treble output (on its original location, out of sight in the pic)

The neck pickup is now always passing through a 20K resistor, not sure if that affects output/tone?

So that's:

* Orion + Series mono - All signals summed with three 20K resistors to the bass output

* Orion + Series stereo - Bridge pickup straight to treble output, Orion and neck pickup summed with two 20K resistors to the bass output

* Series alone stereo - Bridge pickup straight to treble output, neck pickup passing through 20K resistor to the bass output

* Series alone mono - Bridge and neck pickup summed with two 20K resistors to the bass output.

Splitting the new input signal over both outputs could be trickier indeed, luckily for me its not what I need for now. :-)
Would be nice to have as a switchable option though
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1872
Registered: 5-2006
Posted on Friday, March 04, 2016 - 9:14 am:   Edit Post

Here's the third resistor:



I should have noted that the first pic in post #1870 only highlights the changes I've made.
Also added a ground wire, not sure if that's necessary.. (the input is grounded through the housing)
jimmyj
Senior Member
Username: jimmyj

Post Number: 630
Registered: 8-2008
Posted on Friday, March 04, 2016 - 9:53 am:   Edit Post

Wow, did you have your trained ant take that picture? That's a mighty fine close-up!

OK, this makes sense and I'm glad it does what you need it to do. I would say the only possible issue could be that in stereo you may have slightly altered the balance between the bridge pickup and the neck pickup (which always has the resistor in the signal path). But that's pretty easy to compensate for with the rig - or even the individual pickup volumes on the bass.

Nice going!!

Jimmy J
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1873
Registered: 5-2006
Posted on Friday, March 04, 2016 - 10:33 am:   Edit Post

Trained ants!

Everything seemed to be working fine at the last rehearsals, there might have been a slight volume drop on the neck pickup when used stereo + the Orion. That could have been a sonical illusion though, I'll experiment a bit more thorough asap.

Can't wait to implement this in the big rig, I have no "emergency input" currently and with the two extra inputs you can use three basses simultaneously. (did anyone say Big bottom?)

Keep fingers crossed for those noise issues...
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1874
Registered: 5-2006
Posted on Friday, March 04, 2016 - 6:21 pm:   Edit Post

All righty, did some experimenting :-)

Youtube link

This is where the max level indicator is located:



As you can see here, the difference between the Orion passing through the 20K resistor and the straight connection seems to be about 10dB:



Like our dear Jimmy noted, the difference can easily be compensated with the amp levels and the internal instrument gain settings.

Maybe it would be better to have the bridge pickup 20K resistor also hardwired? (like I did with the neck pickup)
Then we would also be just one step away from adding the extra input to the treble output
Maybe Im overthinking this, but I guess this could be done with an Isolation transformer?

jimmyj
Senior Member
Username: jimmyj

Post Number: 631
Registered: 8-2008
Posted on Friday, March 04, 2016 - 10:57 pm:   Edit Post

Here's my latest idea. I'm gonna say it again; I could be wrong! (I'm waiting for Mica to kick me out of here. Ha!)

My funky drawing below is what I think would allow you to play in mono or stereo - with your extra inputs ("front in" and "back in") summing to either the mono output or your two stereo outputs.

The square box is a SPDT switch (we could probably figure out how to incorporate your existing 1/4" jack switch, or you could replace that with a standard jack and wire in a toggle).

With the switch in the lower position (as drawn) the rig runs in mono with all signals summing out of the bass/mono output (top right jack - sorry forgot to label it) with only one resistor in line with each "source"... Actually, now that I look at it, both output jacks would have the same mono signal...

With the switch in the upper position the Series outputs still pass through resistors on the way to the bass and treble outs (in stereo), and your added mono "inputs" do the same - on the way to both the bass and treble outputs.

Again, I am not certain how this will effect levels - from your experiment you may loose 10db on everything... But it should keep the instrument outputs from messing with each other. And switching to mono cuts out 2 of the resistors from your new inputs so the value isn't halved. Turn down the amp before you throw that switch! Hmm, looking again, in stereo the two outputs are actually only 20k apart so not sure that's enough to not be "kind of mono". I still don't know enough.

So I urge you to experiment before you commit to soldering! Find some test leads with alligator clips and a bag of 20k resistors and goof around. Keep that amp turned down though!!

Jimmy J
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1875
Registered: 5-2006
Posted on Sunday, March 06, 2016 - 11:34 am:   Edit Post

Seems to work great Jimmy, you the man! Thanx!

I've tried this setup (minus the 2nd additional input) with the Roland recorder and with the Stereo "rig" setup, with everything connected it seems to work fine (great)

Quiky observation: When the 5 pin plug is removed from the Bass, the 1/4 input "bleeds" a little to the treble out (with the switch in the off position)


If Mica is reading: When will the DS 6 become available and can it be custom ordered from the mothership with this mod? (additional front and back 1/4 input)
That would be completely awesome :-)
fc_spoiler
Senior Member
Username: fc_spoiler

Post Number: 1876
Registered: 5-2006
Posted on Tuesday, March 08, 2016 - 5:26 pm:   Edit Post

Btw: I also "brewed" together a portable powersupply, currently working with four 9V batteries. (like Alembic made for Mark King, Jason Newsted etc for using with wireless)
The two 1/4 outputs work the same way as on the old DS5 (switch in treble output)



Now I will try to find a way of cramping some kind of +/- 18V rechargeable power source in there (most likely will need a slightly larger housing) and it would be great if it could be charged through the 5 pin connector. (male 5 pin connector on the charger)
Also might add a battery level indicator, there are some neat and tiny solutions for that.

I will start a separate thread when I've worked all that out :-)
room037
Senior Member
Username: room037

Post Number: 527
Registered: 9-2003
Posted on Wednesday, March 09, 2016 - 6:09 am:   Edit Post

It's good idea, Flip !

If it will be rechargeable by 5 pin, it's a best way. It means no back panel access.
I made similar one (}18V by four 9V batteries, stereo output and Master volume), but I don't use it now.

Please show me your project.

Eiji

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