Issue with Sansamp VTBass Rackmount DI

Discussion in 'Amps and Cabs [BG]' started by Piggy8692, Jun 11, 2019.

  1. Piggy8692


    Oct 2, 2010
    Northern Utah
    I run wirelessly into the Line 6 receiver and into the Carvin. I bi-amp my highs and lows. I am inserting (tip/ring) the LOW channel on the EQ for my lows and my highs go through the VTBASS into the HIGH EQ Channel. The effects loop on the Carvin goes the tuner.

    My issue is that I can get sound from the Carvin's DI just fine (the Line 6 too), but I only get humming from the VTBASS and nothing from the EQs. I am trying to use the DI outputs from the VTBASS and the Carvin simultaneously to record.

    I've tried changing the bridge and pre/post settings, but nothing seems to be working. When I turn up the XLR output on the face of the VTBASS the humming gets louder, but nothing worth can be heard.


    My explanation is probably not that great, so here's a drawing!

    Hopefully, it's something simple if it's possible. I am not a professional by any means.

    Thank you for your consideration!
  2. BogeyBass

    BogeyBass Inactive

    Sep 14, 2010
    Just use one pre and record.
    Call it a day
  3. Eric Moesle

    Eric Moesle

    Sep 21, 2001
    Columbus OH
    I don’t understand why you would do ANY of this to record, as opposed to using separate channels on the recording board to mix.
  4. If I'm understanding your signal flow correctly (big if), it should theoretically work how you'd like it to. Maybe your TRS/patch cables aren't wired properly internally?

    Can you post a pic of the cables you're using to connect the Carvin to the DBX?

    You say you get no sound from the DBX XLR outs, correct? But are you definitely getting sound from the DBX 1/4" outputs?

    Is the sound you're getting out of the Carvin DI affected by the DBX EQ? IOW, if you fiddle with the channel 1 EQ can you hear a change in the Carvin DI sound? How about channel 2?

    You may expect some hum from the interaction between different devices, which may or may not be resolved via ground lift. But the fact that you've got no output is the bigger issue and you want to make sure you're not inadvertently running inputs into inputs on different devices, which will certainly cause hum and likely eventually cause magic smoke to appear.
    JC Nelson and BasturdBlaster like this.
  5. Disengage Bridge on Carvin.
  6. Absolutely, bridge should be off.
    BasturdBlaster likes this.
  7. Piggy8692


    Oct 2, 2010
    Northern Utah
    I do plan on running separate DIs from both the Carvin and the VT into their own inputs. The mix between the EQed lows and affected highs works just as expected through my cabs, so I don't think it's my TRS cables, but I'll add a picture when I'm back home.

    It still doesn't work regardless if the bridge is engaged or disengaged.
  8. JimmyM

    JimmyM Supporting Member

    Apr 11, 2005
    Apopka, FL
    Endorsing: Yamaha, Ampeg, Line 6, EMG
    Contact Tech 21 later today. They have great support. However, broken cables wouldn't be out of the question by any means.
  9. BogeyBass

    BogeyBass Inactive

    Sep 14, 2010
    Tip send ring return.
    Still needs common connections.
    Or sleeve ground. Both the send return on the EQ need ground or common connections

    Probably just send high/ lows from Carvin to recording interface. Use channel strip in plugin.

    Still don't see the need for isolation seperation or so much EQ

    Carvin needs 3 ring. Other end would be 2 ring for standard equipment. Send return be 2 wires as shown. Both need common sleeve connections though.
    Last edited: Jun 12, 2019
    BasturdBlaster likes this.
  10. coronado3

    coronado3 Supporting Member

    Jun 29, 2008
    Indiana, USA
    Just run your bass into the vt, sansamp signal out to one side of eq to filter off the lows, unaffected output to second eq to filter off highs, each to the two amp returns of the carvin or another power amp. Carvin preamp not used... mic both cabs OR put two DIs after the eqs, before the power amp.
    Clean, solid lows with no breakup and gritty highs.
  11. -Asdfgh-


    Apr 13, 2010
    I'd run a full bandwidth from the bass to the mixing board in addition as you can always reamp, choosing a different cross-over point later. By all means have the amp live in the room for feel. I DI electric guitar too in case I decide the track needs a different amp. Remember to adjust for latency which I sometimes forget to do...
  12. crguti


    Feb 14, 2011
    press the 'active' front button of the VT Bass.
  13. Piggy8692


    Oct 2, 2010
    Northern Utah
    Here is a picture of my connections. The VT is active and turned on..
  14. And still looks like Bridge button is engaged.
  15. you better start over

    with what you are trying to do

    And what is actually working.

    Because you are not making any sense
    And your picture is different from your diagram.
  16. tech21nyc

    tech21nyc Commercial User

    Aug 17, 2010
    Manufacturer: Tech 21
    It would be best to test the VT Bass Rack separately. Preferably out of the rack. My guess is that you probably need to use an isolation transformer. Combining all those units that each have their own ground in addition to possible physical grounding through the rack itself will more than likely result in ground issues.