Opus, is there such a thing.....

Discussion in 'Recording' started by Tommy P., Mar 19, 2002.

  1. Tommy P.

    Tommy P. Well-Known Member

    Opus, is there such a thing as a PCI card extender? What I want to do is, break into the cable before the extended slot, and feed a discrete power source to whatever is in the slot, to isolate it from spurious voltages. The DC power rails are noisy, even with the best power supplies and mobo's. Also, I'd like to put the sound cards in thier own metal enclosed box. I've already fed my Seasound breakout boxes through the 1284 cable this way with great results. Got any ideas? :cool:
  2. Opus2000

    Opus2000 Well-Known Member

    Ummm....no ideas man...you're doing $*^t that I dont normally do..
    I guess maybe I dont know what it is that you are truly looking to do...Is it that you want to put a dummy video card in? What type of noise are you getting? And are you really using PCI video cards? :eek:
  3. Tommy P.

    Tommy P. Well-Known Member

    Most sound cards are drawing 5VDC from the PCI bus. This bus is shared with all the other eqipment on the computer.
    I've found that electrical noise from the computer( mouse movement, hard drive spin-up, fan motors ), can be seen in the Wavelab phase meters, as well as the VU and peak meters,(no source or pre's, just recording silence). With headphones on, and headphone volumes at max, if it is serious, it can be faintly heard as static when the mouse is moved, hard drives spin-up. ect.
    Depending on the quality of the computer's power supply, mobo, ect the noise can vary, but is always there, and raises the noise floor. Some sound cards are designed to filter this noise, but a filter is not as good as an isolated power supply.
    So my solution is to power the PCI cards from their own discrete power supplies. I would also like to mount the PCI sound cards outside the case, in a separate enclosure. I would need a cable that goes into a PCI slot, with a slot on the other end.
    Do you know if an extension cable like this exists, otherwise I'll have to find a way to make one. :confused:

    Tommy P.
  4. Opus2000

    Opus2000 Well-Known Member

    The only thing I know of is the Magna Expansion chasis....


  5. Tommy P.

    Tommy P. Well-Known Member

    Thanks Opus, I figured there must be something out there, LOL, I can't afford it.

    Tommy P.
  6. knightfly

    knightfly Active Member

    Hey Tommy, I know what you mean about the Magma stuff, I can't afford it either. I'm curious - are you seeing this noise even with cards that do all analog outside the computer, like the Layla for example? I know a lot of cards still bring audio into the computer, these are the ones I stay away from like the plague. I subscribe to the old saying,"The best way to get rid of noise is not to generate it in the first place", but that can be a bitch with computers. I was so turned off by Magma's prices that I don't even remember if they use a separate power supply or if they extend power from the computer also. Also, are you using one of the primo supplies with all the extra regulation/filtering ? Maybe, as proud as Magma seems to be of their stuff, you could get enough info from their website to reverse engineer? Just some thoughts, go ahead and laugh, you ungrateful bastard :=) Steve
  7. Tommy P.

    Tommy P. Well-Known Member

    Yep, outboard boxes. I have two Seasound Solo's for an 8x8 24/96 system. The pre's, ADA converters, headphone amps are all outboard. But by some stupid design flaw, the analog electronics in the boxes gets fed from the computer supply with poor filtering. I have all the best power stuff(a homemade Equi-tech-like balanced/isolated line conditioner unit, 50 ampere line filter, premium P/S ect). I havn't run a star grounding system to dedicated technical ground rods yet, but I'll get to it.

    Those Magma products could be built for way less(looks like enermax P/S units ).

    Tommy P.
  8. Fozz

    Fozz Active Member

    Williamsville, NY
    Home Page:

    Do you know if all ad/da converters that are external to the PC have their analog electronics fed from the computer supply? I.e. might the MOTU 1296 exhibit the same problem. This page of theirs

    says: "Like all MOTU hardware products, the 1296 comes with an internal power supply and standard detachable IEC power cable. No wall warts or line lumps."

    Is the above a technically useful sentence or just some marketing mumbo jumbo?
  9. Opus2000

    Opus2000 Well-Known Member

    MOTU boxes indeed have the converters on the outside of the box as well..I dont know what Steve is talking about on the Layla but it is an external box.... :roll:
    Of course the Magma could be made for less...but how else are they going to make money?! By overcharging yo ass!!
    What I definately dont like are cards with the analog connectors right on them and no breakout box to get it away from the computer..converters on a PCI bus are bad..
    It's amazing the RME cards work so well even tho they are on the PCI bus as well!!
  10. Tommy P.

    Tommy P. Well-Known Member

    Like the CardDeluxe, engineering excellence!

    Seasound, M-audio, Terratec,Hoontech/STAudio, Sonorus all use the same ICE1712 Envy24 sound controller chip. For converters most use the 24/96 AKM AK4524 or the newer AK4528(in the RME card).The 192Khz AK4395 and AK5394 are new. I don't know who is using those yet.

    These chips cost about 12 bucks each in quantities of 50.
  11. Nick Driver

    Nick Driver Guest

    One of the biggest sources of induced noise in the studio I've found to be is the darned video monitor... specifically the deflection yoke on the neck of the picture tube. The soundcard or even any audio cable in the vicinity of the video monitor picks up a fair bit of induced EM noise. Guitar pickup coils will pick up this noise something fierce!!! Gonna try a flat panel LCD monitor as soon as I win the lotto and can afford a good 19" unit. Any opinions of these in the studio?
  12. knightfly

    knightfly Active Member

    Hey Opus - welcome to the club of rotten readers! Here is what I said about the Layla's - "cards that do all analog outside the computer, like the Layla for example?" (meaning, the Layla does analog OUTSIDE the computer) Here is what you said - "I dont know what Steve is talking about on the Layla but it is an external box" (meaning, the Layla does analog OUTSIDE the computer) Next argument we get into, one of us hasta choose the other side...

    Tommy, I think part of the price problem with Magma is Mac's - last I heard, the biggest baddest mac (except the one with the special sauce) only had 3 PCI slots, and Mac freaks are so used to paying twice what their computer is worth, why not continue the rape? Hey, have you tried a selection of ferrite beads for decoupling? Those things are like bumblebees, they have no right to fly but they do... Can you see the glitches on a scope when you move the mouse, etc? That might help design a workable filter as a card mod. Dunno, man, sounds like you're further along in reality than I am in surreality...

    Hey Nick, I think the only real strike against flat panels for studio is that they leave your wallet in the same shape (flat) My new layout takes as much of what you mentioned into account as possible - outboard sound cards will be under the desk, about 2-1/2 feet from monitors, with the computer(s) outside. I'm probably going to get a 15" flat panel, keyboard, mouse setup to use as a portable extension from the DAW, which can be taken to an iso-booth (or wherever) and plugged into a cat-5 patch bay, both ends of which will be wired into Belkin Cat5 extenders. With just a pair of the extenders, I will be able to patch one of them into any room in the studio, with the other end going to the DAW. Besides the portability, this will also let me use single coil pickups closer than 4 feet from the monitor. I will still use twin 21" CRT's at the mix position for the extra "real estate" (without buying into such an expensive "neighborhood" as two large LCD's. The only negative I've heard of on flat panels is visual lag on some of the less expensive ones - I don't think this would be a problem with music software, more with action movies. So, save your pop cans and bottles, and drink heavy so you can buy me one too, or one, two... Steve
  13. Jon Best

    Jon Best Active Member

    Just another LCD data point- I took the giant leap of cheap and bought a $300 KDS flat panel with mediocre specs, just to drag along with the rackmount live computer, and it's fine. Not enough ghosting to bother me, bright enough, acceptible viewing angles. I'd be happy to have it on my home computer, or whatever.

    Also, Steve, if you're looking at 21" monitors, I went to surpluscomputers.com and got a 21" Sun/Sony refurb for $320 or so shipped, and it's *really* nice. Flattish screen, really sharp picture, and it's not any deeper than my 17" at home. Highly recommended by me!
  14. Nick Driver

    Nick Driver Guest

    I may have just struck a goldmine... My boss just gave me two 15" KDS flat panel monitors!!!

    The catch is that they are both broken.

    The power supply sections that feed the fluorescent lamps that backlight the screens have failed. I already took one of them apart and it has a couple of visibly (and smelly) fried capacitors on the power supply circuitboard. The video portions are still functioning and you can still see the screen images if you hold them under a light just right. They are out of warranty so my boss was just going to throw them in the trash, so I rescued them. I used to be an electronics tech in a former lifetime so I should be able to fix these if I can find replacement parts.
  15. knightfly

    knightfly Active Member

    Man, some people can fall into an Arab toilet and come out holding a chicken sandwich with extra mayo! Don't forget to look beyond the fried caps to see if there's a deeper reason (shorted diode, etc.) I'd wish you good luck, but yours is already better than mine, so ^#$% off... :=) Since you're newer than me, I'll warn you - yes, I am an incurable smart-ass, and no, I NEVER mean anything negative I say to/about individuals, only about slime-ball, crap-ass, corporate greedy, stupid manufacturers who take my money and only give me one "digit"... All seriousness aside, I hope you get both your goodies to work... Steve
  16. Opus2000

    Opus2000 Well-Known Member

    <<<<Insert Foot Into Mouth>>>>
    LMAO!! I guess that supreme coffee I been drinking here affects the way I read!! So sorry Steve!! Buddy O Pal O Mine!!
    Opus :D
  17. Nick Driver

    Nick Driver Guest

    :) :) :) :) :) :) :) :)

    I figure there might also be semiconductor devices shorted out on the powersupply/inverter circuitboards. There are a couple of oddball no-part-number surface-mount IC chips and individual transistors and diodes there... I'll test the transistors & diodes, replace the caps and picofuses and if that doesn't fix it, I found some usenet articles where folks have replaced their fluorescent tubes with strings of white LEDs and get more light plus less current draw and less heat to backlight the LCD screens.
  18. knightfly

    knightfly Active Member

    Opus - I'd tell you to bite me, but you prob'ly would :=)
  19. knightfly

    knightfly Active Member

    Oh, yeah, almost forgot - toejam goes great with vanilla ice cream and Desenex...
  20. Opus2000

    Opus2000 Well-Known Member

    You would know that wouldnt ya!! hee hee

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