Strange thing happened the other night...

[Ray]

I was doing a recording session at a well equipped studio, I was in the live room with the drummer and my amp was set up in a separate room.

My bass was plugged into a DI box which was plugged into an XLR socket on the wall in the live room. In the room with my amp there was another DI box plugged into the XLR wall socket and a jack cable from that DI box to my amps input.

Sounds pretty normal, right?

Thing is, the sound out of my amp was awful. No low end and loads of midrange. I then plugged my bass directly into the amp and it sounded great as normal. Plugged back into the DI - awful.

There must have been something in between the DI boxes affecting the sound, or the DI boxes themselves?

The engineer said that he's never experienced this and suggested it's probably my amp (Aguilar AG500SC).

Hmm...

Edited October 28, 2009 by Ray

[Bottle]

Umm, not sure you can get away with that, unless the DI boxes are passive types - even then I've not heard of this being done.

Just to clarify, does your signal chain looks like this?

Bass > DI box out > wallbox > DI box in reverse > jack out into amp

In that case, probably the ground was lifted at one end or the other, or attenuation in line. For this to work, the destination DI need to be the passive type, with no active electronics in the way, because you're effectively using it 'in reverse' to normal operations. The source DI can be active or passive, but an active type would have to be battery-powered, because you have no way of injecting phantom power.

Depending on distance, I would have thought that using a matching jack-to-XLR cable for both ends would work better, and avoids the hassle of DI'ing the bass, and ground loops, impedance mis-matches etc.

Anyway, HTH
Ian

PS and this is a 'well-equipped' studio?

[Ray]

[quote name='Bottle' post='639143' date='Oct 28 2009, 03:25 PM']Umm, not sure you can get away with that, unless the DI boxes are passive types - even then I've not heard of this being done.

Just to clarify, does your signal chain looks like this?

Bass > DI box out > wallbox > DI box in reverse > jack out into amp[/quote]

Yes. That's how it was.

[quote]In that case, probably the ground was lifted at one end or the other, or attenuation in line. For this to work, the destination DI need to be the passive type, with no active electronics in the way, because you're effectively using it 'in reverse' to normal operations. The source DI can be active or passive, but an active type would have to be battery-powered, because you have no way of injecting phantom power.

Depending on distance, I would have thought that using a matching jack-to-XLR cable for both ends would work better, and avoids the hassle of DI'ing the bass, and ground loops, impedance mis-matches etc.[/quote]
Is this the usual way to connect a bass to an amp in a different room? i.e. Bass > jack-XLR cable > wallbox > wallbox > XLR-jack cable > amp

Are there other/better ways to do it?

[quote]PS and this is a 'well-equipped' studio? [/quote]
Well equipped, yes. But if the engineers don't know how to use the gear properly what good is it?

It's actually a college where they do training courses for studio engineering, Cubase, Logic, Ableton Live etc.

Thanks

[Bottle]

[quote name='Ray' post='639206' date='Oct 28 2009, 04:29 PM']Is this the usual way to connect a bass to an amp in a different room? i.e. Bass > jack-XLR cable > wallbox > wallbox > XLR-jack cable > amp

Are there other/better ways to do it?[/quote]
Sure! If you've got a cable trap, or just a hole-in-the-wall, then your regular instrument cable should suffice, provided it's long enough. Patching using a XLR is just another way of doing it. At the end of the day, it's still unbalanced, so try to keep the runs short.

Using the DI boxes in that back-to-back configuration brings in all sorts of problems - impedance mismatches, ground loops, ground lifts etc.

[quote name='Ray' post='639206' date='Oct 28 2009, 04:29 PM']Well equipped, yes. But if the engineers don't know how to use the gear properly what good is it?

It's actually a college where they do training courses for studio engineering, Cubase, Logic, Ableton Live etc.[/quote]
Sounds typical - all the gear but no idea

Oh, well. Chalk it up to experience. And your amp sounds like it's fine - go bother the 'engineer' about his comments

Have a good one, Ian

[51m0n]

if they have one of those XLR to phonos incorrectly wired you could get all sorts of phase nastiness I would think.

Is your bass active?

If the jack into said bass was active, then any amount of weirdness may happen due to the stereo socket in the bass used to trigger the active-ness I would imagine.

Short answer, no IME a jack to jack lead to a wall box and a jack to jack from next wall box to amp would be more normal ie most wall boxes also have some nice jack input/outputs on them.

Course other people may experienced other ways of wiring up to achieve this.

[Ray]

[quote name='51m0n' post='639227' date='Oct 28 2009, 04:52 PM']Is your bass active?

If the jack into said bass was active, then any amount of weirdness may happen due to the stereo socket in the bass used to trigger the active-ness I would imagine.[/quote]
Passive Fender Jazz.

Oh well, it was only a session job anyway. The guy paying for it was happy with the result.

Thanks guys!

[fenderiko]

[quote name='Ray' post='639247' date='Oct 28 2009, 05:09 PM']Passive Fender Jazz.

Oh well, it was only a session job anyway. The guy paying for it was happy with the result.

Thanks guys![/quote]

Hi Ray ,
+1 for all the above. but also your amp not only functioning as an amp but have [b]a very good [/b]DI on it ( why not using Bass>Amp/DI in room no cab > wall>control room ) so, as any engineer will tell you , having millions cables and reverse pluggings and what not is going to make your sound like hell BUT , Also , it sounded like the control room has only taken your DI sound with no amp feed and once adding the fact that you are using a passive J bass that already have a weak signal and very dry full of mids you would have trouble with sound. when the engineer is quickly rushing to blame my equipment I have a red alarm suggesting that the engineer knows F@%K ALL. -
:)you got payed !
R

[Fraktal]

Epic fail. Assuming your amp projects a good tone, the "engineer" has no excuse.

[Ray]

[quote name='fenderiko' post='639764' date='Oct 29 2009, 09:39 AM']Hi Ray ,
+1 for all the above. but also your amp not only functioning as an amp but have [b]a very good [/b]DI on it ( [b]why not using Bass>Amp/DI in room no cab > wall>control room[/b] ) so, as any engineer will tell you , having millions cables and reverse pluggings and what not is going to make your sound like hell BUT , Also , it sounded like the control room has only taken your DI sound with no amp feed and once adding the fact that you are using a passive J bass that already have a weak signal and very dry full of mids you would have trouble with sound. when the engineer is quickly rushing to blame my equipment I have a red alarm suggesting that the engineer knows F@%K ALL. -
:)you got payed !
R[/quote]
I did suggest this but they wanted to mic the cab as well and my speakon cable wasn't long enough to have the head and cab in separate rooms. He did use the DI on the head but it still sounded like crap because of the messed up signal going into it.

Yeah, I think the same when engineers blame equipment!

And yeah, I got paid!!

[Ray]

[quote name='Fraktal' post='639821' date='Oct 29 2009, 10:31 AM']Epic fail. Assuming your amp projects a good tone, the "engineer" has no excuse.[/quote]
If I ever work with him again I'll politely suggest using a different method as described above.

[fenderiko]

[quote name='Ray' post='639854' date='Oct 29 2009, 10:57 AM']If I ever work with him again I'll politely suggest using a different method as described above. [/quote]

Also ,
is it possible that your Amp/DI was set on Pre Eq ? (Pre Eq Button on the amp )
in which case your eq would be flat to the desk but amp still sounding good once you are next to it.
hmmm,,,,

[Ray]

[quote name='fenderiko' post='639899' date='Oct 29 2009, 11:41 AM']Also ,
is it possible that your Amp/DI was set on Pre Eq ? (Pre Eq Button on the amp )
in which case your eq would be flat to the desk but amp still sounding good once you are next to it.
hmmm,,,, [/quote]
No, it was post EQ.

Because the DI sucked out all the low end and somehow boosted the mids I had to compensate with extreme EQing and made a point of checking the pre/post button.

[tayste_2000]

Sounds like a phasing issue to me

[Toasted]

So, your amp worked fine from plugged directly into your bass - but not when plugged through his Heath Robinson setup . . . aaaand that's your amps fault?

Right!

[Higgie]

[quote name='Toasted' post='640205' date='Oct 29 2009, 04:32 PM']So, your amp worked fine from plugged directly into your bass - but not when plugged through his [s]Heath Robinson[/s] Robinson Cruesoe setup . . . aaaand that's your amps fault?

Right![/quote]

Fixed

[Musicman20]

This isnt your amps fault.

[Johnzy]

its definately a phase issue. either one of the cables has been wired the wrong way round or there was a polarity switch engaged, some di boxes have this.
surely the engineer should have noticed this!!!!

[JTUK]

agree..I'd be thinking it isn't the amp and if you have used this before in the studio then it is probably the monkey-brained engr