VO-BB - 19 YEARS OLD!

[tokyofan]

I've go an audio out cable leading from the back of my M-box stretching to a vocal booth nearby and am using an earphone. But when talking into the mic there seems to be a slight delay to my ear...almost an echo effect. How can I remedy this. Also, using an RME A/D-D/A converter...should I use the phones out of that instead?
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www.chriskoprowski.com/en

[Edo]

If you turn the 'mix' control (2nd up from the bottom) all the way anti-clockwise, you send only the INPUT of the Mbox1 to the monitor-outputs. If you slightly turn it to the right (as I expect will have happened) you also get the playback signal to your headphones, which will have the delay due to the latency between processing en I/O from and to your host computer.

[tokyofan]

Thanks!
OK, I've got the 'mix' button turned up just a little and the headphone volume knob up higher and getting no detectable delay. However, I'm now getting some slight hum or static. Should the 'mix' button be all the way to the left?
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www.chriskoprowski.com/en

[Edo]

When tracking... yes.

[tokyofan]

I have to retract what I said before. I'm still getting a noticeable delay. If I turn the mix knob all the way to the left I get nothing to my headphones. I can't seem to monitor just the incoming analog signal.
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www.chriskoprowski.com/en

[Edo]

Okay... from the top:

And let's forget about the RME for now... just unhook it.

Turn the knob [input - playback] all the way to the left. Arm the channel for recording. You really should hear the direct signal now, else you're listening from the wrong output. If you still hear delay, try muting the audio from the channel you're recording to. Do you hear difference between the headphones outputs on the nack and on the front?

Please also explain how you hooked up the RME?

[Ed Gambill]

Better yet if you have RME gear why are you using a M-box?
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[tokyofan]

I should probably explain the other gear I'm using in conjunction with the Mbox. I'm using a Grace Design preamp and an RME ADI-2 A/D-D/A converter. The Grace runs into the RME's analog inputs. And the RME is connected to the M-box via SPDIF cables. And I'm monitoring out of the MBox's rear headphone jack. So, the M-Box is effectively a dongle.

When the mix knob it turned all the way to the left I get no signal to the headphones. If I turn it up a little I do get a signal but there seems to be a very very short delay. Muting the rec track cuts the signal. Monitoring from the front or back of the Mbox sounds the same. The Grace has no headphone jack. and there's no improvement monitoring out of the RME.
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www.chriskoprowski.com/en

[georgethetech]

Ah, now it makes more sense. That is a very high quality signal path.
I'd strongly consider either getting headphone amp or a simple mixer and monitoring directly out of the Grace while tracking.
There could be an inherent delay on the Mbox while monitoring SPDIF.
Search duc.digidesign.com for help..
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[Vocalvoodoo]

Hi Chris, fancy meeting you here!

Everything sounds normal from what you are describing. When feeding signal to the Mbox via S/PDIF, you will hear no audio with the mix knob all the way left, so you do want it all the way right if monitoring through the MBox. It sounds like your H/W buffer setting is too high. To lower it, which will lower your delay, go to Setup > Playback Engine, within Pro Tools. There you will see the option to change your H/W Buffer size. I'm on an MBox 2, so I'm not sure how low you can go with the first MBox. I have mine set to 64 samples and the latency is pretty much unnoticeable. Before switching to Pro Tools 8, I could only go as low as 128 (I think), and there was such a slight delay even at that setting that is was almost unnoticeable. (the lower the buffer setting, the more chance you have for stop errors if your computer isn't fast enough)

On a side note, when you are changing those settings, never tick the RTAS Engine box. If you do, Pro Tools will ignore errors that may stop a recording such as the H/W buffer being too low. The problem there is that if your computer is struggling at a low buffer setting, you'll wind up getting pops and clicks on your recording.

Have you always had this problem, or is it something that just started happening?

If you want true latency free monitoring while recording, Soundgun is right on the money.

EDIT: To answer your question about the ADI-2 headphone out, you will probably get the same delay through it. Well, at least that is the case with my Metric Halo when hooked up the same way as your rig.
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Josh Mahler
http://www.vocalvoodoo.com

[tokyofan]

Hi Josh! I didn't realize anyone had replied to this (so ignore my email inquiry!). YES, reducing the H/W buffer size to 256 samples (lowest) does make a difference (not perfect but close). However, at that low rate I'm getting quite a lot of CPU interrupts. So, maybe I need to find a hardware solution. If I bought a small headphone amp would I plug that into the Grace's analog out?

I'm not sure I've always had this problem...didn't really use an earphone during tracking until recently.

What is Soundgun?
Thanks!
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www.chriskoprowski.com/en

[tokyofan]

At Josh's recommendation I picked up a Samson S-monitor today.
The standard set-up is to plug the mic directly into the Samson and then use a second mic cable to plug into the Grace (or mixer)...thus monitoring the incoming analog signal. I tried it and it works OK! But I'm wondering if putting the Samson between the analog signal and the preamp will affect the signal in some way?

I also tried to connect the Grace's balanced outputs to the Samson's 'Stereo Input' jack via 1/4" cable. No signal.

But plugging into the Samson's "Mix Thru" jack DOES seem to work OK!

So which option is better? Using a 1/4" cable into the "Mix Thru" jack or using a mic cable going thru the Samson?
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www.chriskoprowski.com/en

[Vocalvoodoo]

Hey Chris,

I'd definitely go with the "mix/stereo thru" option so the Samson doesn't degrade your mic signal, as you mentioned.

So if I'm understanding correctly, you have the XLR out from the Grace going to the RME and the 1/4 inch out from the Grace is going to the Samson? I'd say that is the best way to have everything wired.
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Josh Mahler
http://www.vocalvoodoo.com

[tokyofan]

Hey Josh,

Yep, that's how it's wired and it sounds GREAT! Very happy with it! Thanks again for the suggestion!
Chris
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www.chriskoprowski.com/en

[georgethetech]