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haddimudd
Advanced Member
Username: haddimudd

Post Number: 234
Registered: 6-2002
Posted on Monday, January 09, 2012 - 10:17 am:   Edit Post

Has anybody done this? Going direct from the Series II 5-Pin XLR output to 2x 3-Pin-XLR inputs of a recording device (mixer console or - as in my case - an Edirol FA-101 (http://www.rolandus.com/products/productdetails.php?ProductId=702)) and make use of its phantom power instead of using the DS-5R or batteries?

Would any Y-cable do or do different wirings exist that I need to take into account? I found some wiring info here: http://www.dvinfo.net/forum/sony-xdcam-hd-cinealta/88803-5-pin-xlr-wiring-configuration-2.html

Does the same wiring apply to the Series II 5-Pin XLR?

Can anybody recommended any readily available cables? Or maybe just a simple Y-adapter (w/out cable) to be used with the cable I already have?

Thanks a billion!

Hartmut
sonicus
Senior Member
Username: sonicus

Post Number: 2248
Registered: 5-2009
Posted on Monday, January 09, 2012 - 11:03 am:   Edit Post

Hartmut,
Here is the PIN OUT for the ALEMBIC 5 pin
pin 1 ground
pin 2 neck pickup
pin 3 bridge pickup
pin 4 +V
pin 5 -V

You need either active or passive DI coupling .
1) Find an Alembic IN-2(passive transformer DI coupling)
OR use 2 Alembic F-1X preamps ( they have a nice XLR DI )
OR get a multi channel DIRECT BOX such as the PROCO -4A (passive transformer DI coupling)
(i have one , it works well)
http://www.musiciansfriend.com/pro-audio/pro-co-db-4a-quad-direct-box/151518000000000?src=3WWRWXGB&ZYXSEM=0

I have tried all the above with out problems

Viel Spass !

Wolf
jimmyj
Advanced Member
Username: jimmyj

Post Number: 333
Registered: 8-2008
Posted on Monday, January 09, 2012 - 12:22 pm:   Edit Post

Hartmut,

Wolf correctly described the pin-out. Although I don't fully understand phantom power I believe the current draw required for these instruments is too high to be powered that way. The power supply that comes with the instrument provides +/- 18VDC and would be the best way to operate. Or you could pack a ton of spare batteries...

Since the instrument's audio output is also unbalanced you would not gain any advantage by wiring it directly to XLRs. You could do as Wolf says and use DI boxes ... but before you add more pieces to your recording rig you should try plugging directly into the 1/4" inputs of your audio interface.

And I suggest trying inputs 3-8 on the back, bypassing the device's internal preamp. Your Series-II should be able to provide enough level to make that work, using the master volume on the instrument to lower it. This would be your cleanest way in.

If there is not enough level that way (remember you can adjust the trim pots on the back of the instrument) then next try 1/4" into the front and experiment with the "Hi-Z/Lo-Z" switch to see which way works best.

The 3rd way would be to use DI box(es) and the mic inputs.

Good luck!
Jimmy J
sonicus
Senior Member
Username: sonicus

Post Number: 2251
Registered: 5-2009
Posted on Monday, January 09, 2012 - 1:05 pm:   Edit Post

I like Jimmy's suggestions as well.

The Alembic Series I/II +/- 18 V through the cable should not be confused as Phantom Power because it is NOT. There have been various specs on Phantom Power over the years . Currently 48V is the popular standard.

All voltages specified are DC

(Message edited by sonicus on January 09, 2012)
dfung60
Senior Member
Username: dfung60

Post Number: 529
Registered: 5-2002
Posted on Monday, January 09, 2012 - 5:19 pm:   Edit Post

The adapter you're asking about isn't trivial to make. The problem here is that the 3-pin XLR mic connections expect a balanced signal, but the stereo outputs that come out on the 5-pin Alembic XLR are unbalanced signals. They just happen to be on a similar family of connectors.

The Alembic outputs have a hot and ground conductor. That's like a regular passive bass plus a buffering preamp that makes a low-impedance output that eliminates interactions from cables and the amp front-end.

That's different than the balanced wiring of a microphone. On a mic, the signal is carried on a matched set of conductors and is completely separate from the grounding and shields. At the signal source and mixing board end there are transformers that recover the signal by recreating the difference between the +/- signal conductors. Inside the mic cable, the +/- conductors are twisted together tightly. If the cable passes through an electromagnetic field that would cause hum, both the +/- wires pick up the noise, but the differential combination at the receiving end will remove anything that wasn't at the source. This kind of noise reduction doesn't work with unbalanced connections (like an instrument).

You actually can connect the two conductors of an unbalanced connection to a balanced input, but you won't gain any of the normal benefits of the 3-wire connection.

The adapter you want to make would basically be two DI boxes. The transformer or active circuit in the DI box is what makes the conversion from unbalanced to a differential signal. You could put a DI transformer in the bass, but if you wanted to keep stereo out, you need even more pins on the connector.

On the Alembic 5-pin connector, there are two unbalanced, lo-z + signal outs, a common ground, and +/- remote power from from the power supply. The onboard batteries are a "perfect" power supply - since the power comes from chemistry, there's no opportunity for hum to leak in. Putting the AC power supply in the blue box lets Alembic make a super-high quality filtered power supply with low noise. This is really a remote power supply since there are dedicated power wires in the cable.

A phantom power supply is a clever trick that takes advantage of the differential microphone connection. They actually pump 48VDC power down the microphone signal lines. The microphone can be powered by connecting to the signal lines, but when you take the difference between the signal lines, the DC power is cancelled out. Many mixing boards provide enough power to power your bass, but you can't be sure of that. Microphones usually only need a small amount of power to charge a mic element, but your bass is powering a bunch of preamps, and maybe LEDs too.

David Fung
haddimudd
Advanced Member
Username: haddimudd

Post Number: 235
Registered: 6-2002
Posted on Tuesday, January 10, 2012 - 1:04 am:   Edit Post

Thanks a lot, guys!

Well, long story short: I have no (i.e. can't use) batteries on my Series II (reasons as mentioned here: http://alembic.com/club/messages/411/10807.html?1314758340) and my DS-5 introduces a constant (not a directional) hiss which I was trying to avoid by avoiding the DS-5 in the first place and by making use of "phantom power" of the FA-101 instead, but as you taught me now life is never that easy. Thanks a lot, David, for your in-depth explanation!

Wolf, of course I don't have an IN-2, but thanks a lot for pointing that device out to me as I had never heard of it before. I read through all the reference threads by now. Sounds interesting enough.

For the suggested F-1X solution (I do have one, but not two) I would need to use my DS-5 to power my electronics again and, as mentioned above, that's what I am trying to avoid and seeking alternatives for.

When you suggest a DI-box, isn't that what I have with my Edirol FA-101 already or would it give me something different (besides the extra inputs which I don't need)?

So, no going direct without battery power or DS-5/IN-2?

Needless (or maybe not so needless) to mention that without batteries my bass doesn't have a 1/4" jack output either, only the 5-Pin output. I guess I was an idiot when deciding to have the bass built without the option of using battery power.

Hartmut
jimmyj
Advanced Member
Username: jimmyj

Post Number: 334
Registered: 8-2008
Posted on Tuesday, January 10, 2012 - 9:41 am:   Edit Post

Hartmut,

We need to further explore the audio problem you describe when using your DS-5, because connecting that way should be dead quiet...

You say "hiss" and not "hum", yes? Hum would mean a ground disagreement between devices or some induced pickup interference, but hiss... Did you try to play a note? Is it possible the gain of either the instrument or the interface was incorrectly high? Master and PU volumes are up to normal levels? Do you set the Q-level controls set to extreme boost?

Describe that problem a bit more for us.

And now, here is a geeky alternate way to power your WILD looking axe. I only mention this because it's possible but it is unlikely that this method would yield a different result from using your DS-5. So before you go this direction we need to get to the heart of the issue...

There have been a handful of Artists who have needed to play their Series instruments wirelessly. If you ever saw the strap used to do that ... it looks like an ammo belt (and like you need MORE weight to carry around!) But you CAN build a battery powered DS-5 if you want. +/-18 means at least 4-9V batteries or if you wanted to go crazy you could use 6-6V motorcycle batteries. You would still use your 5-pin cable in this case but the instrument would not be connected to mains power. Again, I'm only mentioning this because it's an alternative way to power your instrument BUT I do not believe this would solve your problem...

Tell us more.

Jimmy J
jimmyj
Advanced Member
Username: jimmyj

Post Number: 335
Registered: 8-2008
Posted on Tuesday, January 10, 2012 - 10:10 am:   Edit Post

One other thing - after reading a bit about your "double" bass... You mentioned that you might like the idea of having the different necks output to different amps instead of having always stereo pickups. I think that could be done as a mod without too much difficulty. Setting it up so the fretted neck output would appear in mono coming from output A and the fretless neck would come from output B. It would involve a few summing resistors and a bit of internal rewiring but it's certainly possible. Just a thought.

That bass is a work of art!

Jimmy J
dfung60
Senior Member
Username: dfung60

Post Number: 530
Registered: 5-2002
Posted on Tuesday, January 10, 2012 - 11:32 am:   Edit Post

Hartmut -

Aha! From your description, I think your DS-5 is bad.

If you've ever looked inside, you'll see there's not much in there (I only have the little blue ones). The AC line cord goes into a transformer which tweaks the voltage. The secondary output of the transformer goes to a tiny square component mounted on the back wall of the DS-5. This little box is a rectifier which converts AC into DC. The DC supply goes into the two enormous capacitors which store up power to smooth out the supply, then it's off to the 5-pin connector.

When you have a hum problem that's not directional and won't go away, it means that the rectifier has probably gone bad. Inside the rectifier there are 4 diodes. They must be a precisely matched set or residual AC will leak through (that's called "ripple"). In audio systems, the ripple is usually hum at the line frequency.

I'd contact Alembic about getting the power supply checked out, and you should be in business again. It's probably the cheapest part inside the DS-5 (if the part is even $10, I'd be surprised).

You should have them do the fix though. You can get an unpleasant shock from those capacitors when they're charged up. And if you mess up the replacement of the rectifier, it will blow up your electronics and neck LEDs when you power the bass up! So you definitely want to get this fixed before it gets worse.

If you're adventurous or have a geek friend, you can confirm the problem with an oscilloscope. If you attach a probe to the DC power wire in the bass, you should see a dead flat line on the scope. If you see bumps at your line frequency (60 or 50 Hz), that's the hum from your bad rectifier.

David Fung

P.S. I saw your bass while it was in the final stages at the mothership. I was up in Santa Rosa and stopped by Alembic to say hello. Ron grabbed me and said "you've GOT to check this out..." The wood and finish work was done, but only part of the electronics were in. Awesome!
sonicus
Senior Member
Username: sonicus

Post Number: 2257
Registered: 5-2009
Posted on Tuesday, January 10, 2012 - 1:32 pm:   Edit Post

I think David Fung is on the right track . I was thinking my self that it could be a power supply problem as well . Just like he wrote .
jimmyj
Advanced Member
Username: jimmyj

Post Number: 336
Registered: 8-2008
Posted on Tuesday, January 10, 2012 - 4:59 pm:   Edit Post

As long as it's "hum" he's taking about (I guess that's why he said non-directional...) it certainly could be a problem with his DS-5. It could also simply be a ground disagreement between his Alembic PSU / his Roland piece / and his computer...

Does this noise occur with the DS-5 and an amp?
Jimmy J
byoung
Senior Member
Username: byoung

Post Number: 1325
Registered: 12-2004
Posted on Thursday, January 12, 2012 - 4:39 pm:   Edit Post

Or DS-5 and Headphones? I'm convinced that I have issues that are getting introduced somewhere between my DS-5 and my amp.

If you go straight to headphones, and there are no issues, it eliminates the DS-5 from being the sole cause.

Bradley
811952
Senior Member
Username: 811952

Post Number: 2114
Registered: 10-2003
Posted on Thursday, January 12, 2012 - 5:34 pm:   Edit Post

Perhaps it's just a bad cable? Check the ends for broken connections and wiggle it to see if that changes anything or makes any noise. A loose ground wire at either end could make it pickup any hum in the room, especially dimmers and such. If it's the cable, I'd just cut a foot off of each end and re-solder the A5 connectors. It's worth checking I think..

John
sonicus
Senior Member
Username: sonicus

Post Number: 2266
Registered: 5-2009
Posted on Thursday, January 12, 2012 - 5:53 pm:   Edit Post

Before any cutting of a cable is done it should be checked for continuity, Each conductor one at a time. There are many ways to check for continuity , A Multi-meter ; VTVM, VOM or DVM. You can use the resistance scale on a meter . If you do not own a multi meter then Battery and a light bulb in a series circuit . If the bulb does not light on there is NO continuity . Don't cut anything before you test continuity .
Thank you very much __ LOL __
811952
Senior Member
Username: 811952

Post Number: 2115
Registered: 10-2003
Posted on Thursday, January 12, 2012 - 6:55 pm:   Edit Post

Yes, don't cut it unless it's bad!

John
edwin
Senior Member
Username: edwin

Post Number: 1110
Registered: 5-2002
Posted on Thursday, January 12, 2012 - 10:34 pm:   Edit Post

"If you do not own a multi meter then Battery and a light bulb in a series circuit ."

Wolf, that is so old school! I think we both remember the days when things like that were right at hand for all growing bass players and experimenters! I can just imagine the wooden board with the ceramic bulb holder and a knife switch along with some screw terminals with some nice cloth covered wire.
edwin
Senior Member
Username: edwin

Post Number: 1111
Registered: 5-2002
Posted on Thursday, January 12, 2012 - 10:36 pm:   Edit Post

"If you do not own a multi meter then Battery and a light bulb in a series circuit."

Wolf, that is so old school! I'm sure we can both remember the days when those items were right at hand for the young bassist and experimenter. I can just see the wooden board with the ceramic bulb holder, a big knife switch and some screw terminals all connected with some nice cloth covered wire.
haddimudd
Advanced Member
Username: haddimudd

Post Number: 236
Registered: 6-2002
Posted on Thursday, January 12, 2012 - 11:50 pm:   Edit Post

Thanks again, guys, for all your good thoughts!

I am planning to make some example recordings of the noise for you to hear exactly what it sounds like. Unfortunately only when I tried to connect my FA-101 to my new computer I realized my new computer doesn't have firewire, thus I couldn't connect the FA-101. Now I ordered a USB device instead and expect it in the mail today, so possibly the weekend will allow me to finally get some sound bits together for you.

I also had a simple Behringer UC6102 Guitar interface lying around and did some testing with it during the last days.

What I can say so far is this:

I go directly from the DS-5R to the recording input. (Bradley, can I connect headphones to the DS-5R?)
The noise is audible there already, although I must admit it is less annoying to me now than how I remembered it from the last time I tested it. It probably grew in my memory over time. But it is there nevertheless. "Dead silent" is not what I would call it.

The noise ("hiss", "hum", whatever) is non-directional. It is present even without the bass connected to the DS-5R. I guess that's an important insight because it should eliminate the possibility of the bass and the cable being the source.

What Jimmy says is what I thought too: "It could also simply be a ground disagreement between his Alembic PSU..." and, well, maybe not necessarily with my computer because the noise is present even when connecting to an amp instead of the computer, if I remember correctly. I sold my power amp therefore I can't test it right now.

I'll keep you posted when I recorded my example sound clips.

Thanks to you all!

Hartmut
sonicus
Senior Member
Username: sonicus

Post Number: 2267
Registered: 5-2009
Posted on Thursday, January 12, 2012 - 11:57 pm:   Edit Post

Edwin , yes I made a nice wooden panel with various knife switches . SPST.DPDT , SPDT . I had those ceramic bulb holders as well . I really felt swell when I added the little volt meter and potentiometer and electric motor with a prop from a rubber band airplane , do you remember those ! lol ___ But i did not have the cool cloth wire , I had to settle with 18 g bell wire from the corner hardware store with plastic insulation. BIG fun at the time for an eight year old! I remember my father saying when I was not making lots of noise and tinkering " was machst du schon wieder" ?
(what are you doing again ?)
sonicus
Senior Member
Username: sonicus

Post Number: 2268
Registered: 5-2009
Posted on Friday, January 13, 2012 - 12:40 am:   Edit Post

Hartmut , to answer your question :

Yes, You can connect headphones to your DS-5R. If you want to hear in stereo get 2 male 1/4" mono plugs (TS tip, sleeve) that bring both channel A&B to a female stereo jack (TRS tip,ring, sleeve). make sure that the female is the correct specifications to connect to your headphones . Plug your head phones into the female . This in a common adaptor that can be purchased easily .

The amount of volume perceivable on your headphone will be dependent on the sensitivity and impedance of the head phones and and the preamp gain and volume knobs on your bass.

It will be important in your trouble shooting process to rule out problems through the systematic process of elimination this way .
haddimudd
Advanced Member
Username: haddimudd

Post Number: 237
Registered: 6-2002
Posted on Friday, January 13, 2012 - 12:51 am:   Edit Post

Thanks, Wolf!

I just gave it a shot but the volume is too quiet to judge the noise. Maybe my headphones aren't too great for that. I'll wait for the USB unit today and see how it goes from there.

Thanks again!

Hartmut
811952
Senior Member
Username: 811952

Post Number: 2116
Registered: 10-2003
Posted on Friday, January 13, 2012 - 6:12 am:   Edit Post

You might also play with the routing of the cables between the power supply and the computer/input module. Computer power supplies, motherboards and other electronic devices (iPod? cell phone?) have been known to produce quite a bit of hash (the other kind) if you run unbalanced audio cables nearby.

John
sonicus
Senior Member
Username: sonicus

Post Number: 2270
Registered: 5-2009
Posted on Friday, January 13, 2012 - 6:47 am:   Edit Post

John , yes ! agreed___ and some very strange sounds . There were in fact many reports and complaints to Digidesign with the MBOX2 USB model in that regard, I heard such intermittent noise my self that was remedied by such means as you mention. I also have had a similar problem with a DAW HUI MIDI type of controller that once was so annoying that I had to mix with a mouse for a few hours until I figured out that problem.That HUI was controlling an old Protools TDM system. EMI / EMF is often the culprit. I have been fighting off 'Smart Meters" with the utility company (PG&E)for that reason . I wrote a report for the CCST in that regard. ( California Council On Science and Technology) I have also been active with the EMF Safety Network for similar reasons including public safety and the fact thats some folks really do have bad reactions to EMF even health wise ;asthma , tinnitus ,head aches ,etc

http://www.ccst.us/projects/smart2/ ( scroll down to personal accounts for my report ; type in guest for the passwords)

http://emfsafetynetwork.org/


(Message edited by sonicus on January 13, 2012)
mica
Moderator
Username: mica

Post Number: 7580
Registered: 6-2000
Posted on Friday, January 13, 2012 - 10:27 am:   Edit Post

Dad is think something is awry with the power supply as well. Maybe you can find one nearby (club member or store) to compare? If not, I'll have to send one your way. Let me know.

Also, Alembic Club really rocks! I really appreciate everyone's willingness to help.
haddimudd
Advanced Member
Username: haddimudd

Post Number: 238
Registered: 6-2002
Posted on Friday, January 13, 2012 - 11:17 am:   Edit Post

Yes, Mica, definitely thanks to everyone!

I guess, I will do what David suggested and take a look inside the DS-5R to see if anything looks suspicious. Thanks a billion for the great and detailed instructions, David!

And hopefully I can record the sound examples tomorrow.

Mica, would you know any Alembic users or stores located near Lake Constance in Germany (or Austria/Switzerland)?

Hartmut
mica
Moderator
Username: mica

Post Number: 7581
Registered: 6-2000
Posted on Friday, January 13, 2012 - 1:00 pm:   Edit Post

Station Music is only a couple of hours away if you are ever up in Jettingen-Scheppach. I say a couple of hours like it's nothing, you know since we had driving adventures before!

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