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rnd
12-17-2003, 03:07 PM
Is anyone using an outboard mixing console in their current rig? If so, which manufacturer are you using? Are you having any problems, either with a particular manufacturer or getting the hardware to work with VT3?

Is anyone using ProTools as a mixing source?

Jim Capillo
12-17-2003, 03:08 PM
I've got 3 Mackies I use, depending on the number of inputs I need.

mgrusin
12-17-2003, 03:55 PM
I haven't outgrown my 10-year old Mackie 1202. Everything in and out goes through it, thus I haven't been overly bothered by the level/metering issues others have mentioned. Bought it used, it's built like a tank and still going strong.

-MG.

Tom Wood
12-17-2003, 04:01 PM
Recently got a Mackie 1202VLZ on eBay and it is great! I don't have a BOB so I bought a splitter that has a 1/8" stereo plug into the VT card on one end, and splits into two 1/4" TR plugs on the other end that each get a channel into the Mackie. Works great.

TW

rnd
12-17-2003, 04:47 PM
Thanks for the info. I plan to use a Mackie (or equivalent) or the output from an automatic mixer (the applications are for a city council chambers and a distance education suite).

Since you all use Mackie's, have you run into any hum/buzz/RF interference problems? This has been a problem in the installed sound reinforcement world, but I'm not sure if it has affected this part of the universe.

Jim_C
12-17-2003, 05:05 PM
mackie 1604's

Sometimes, but it's never been the Mackie's fault.
They are clean as a whistle.
Usually caused by a ground loop in my case and just about always fixed by using a 79cent ground lifter or plugging the offending device into another circuit.

videoguy
12-18-2003, 08:24 AM
mackie ROCKS ths toast. we use a 24x4 mackie vlz board it is awesome i recomend getting a board with 4 busses that way you will never have feedback loops by having the toaster going into the board at the same time the board is outputting to the toaster. we bring the toaster inputs in on busses 1and 2 and output to the toaster from busses 3 and 4
this also allows us to have a compressor wired in at all times and all we have to do to use it is assign and input to the buss its on

Tom Wood
12-18-2003, 08:42 AM
Hey videoguy,

I'm doing some voiceovers for a TV show I'm developing and I'm trying to get that 'big broadcast sound'. I have a compressor between the microphone and the recorder, but I don't know how to set it. Any suggestions? I'm recording to disk using Wavelab, which has additional tools.

Thanx,

TW

videoguy
12-18-2003, 08:58 PM
well i am no expert but maybe i can help some:

There are no exact settings for your compressor it depends on any number of variables. what i would do to calibrate it is record on tape or cd a 1k tone for about 10 mintues play this through your system and just mess with your levels and such till you get good clean sounding consistent level signal.

to get that big broadcast sound i woulr bring it in to wavelan run a normalize filter on the piece first. then i would run a stereo expand on it. i would then use EQ to boost the mids and low mids this is where voice occurs in the dynamic range. then i would add a tad bit of reverb. i would do a couple different versions of this just mess around with it then i would record it on to vhs tape and then go play it through a consumer vcr and tv once it sounds good on that then you are good to go .
hope i helped some

Jim Capillo
12-19-2003, 04:25 AM
You need to invest in a good microphone and setup an area that you can record in that will give you a minimum of reflections and boom. The rule here is GIGO - garbage in, garbage out. With a 79 cent mic, I doubt you'll ever get the sound you're looking for. The voice itself is also quite important.... ;)

Get yourself a pop shield. Markertek has those. They also have portable recording enclosures, if you don't have an area that you can convert to a suitable booth. http://www.markertek.com

You probably want to EQ, not use a compressor (at least at first). With careful EQ and level setup thru the board before you record, you probably won't need to attenuate the signal at all, unless they are shouting into the mic. :D

Some places that sell good quality mics are

Musician's Friend - http://www.musiciansfriend.com/srs7/sid=031219031729067075012152283057/g=rec/search/c=4601/it=NLFO1/fc=0/td=0/d=tn/s=mics

Music 123.com -
http://www.music123.com/Department/?d=7&dd=954727726

Also, check out your local Guitar Center - they have a ton of stuff there too.

Voice recording is not an "exact science", because not every voice is the same. Experimentation is the ticket here. You'll quickly learn what sounds good and what doesn't.

Good luck!

Tom Wood
12-19-2003, 06:23 AM
Thanks Guys,

I'm using an AT 3035 mic thru an FMR Audio RNP/RNC combo from a padded closet to a Digital Audio labs 24/96 sound card, so I think I'm getting at least clean sound to start. It's that low end thump that I'm missing. I'll try the EQ, expander and other tools.

Yeah, Guitar Center is great, but I still miss Mars Music.

TW

Jim Capillo
12-19-2003, 08:51 AM
Originally posted by Tom Wood
........but I still miss Mars Music.



Never had one around these parts. Did Musician's Friend buy the bones? If you click on http://www.marsmusic.com you get Musician's Friend.

:confused:

Tom Wood
12-19-2003, 09:50 AM
Maybe so, the store manager at Guitar Center is the same guy that ran the Mars Music store. And the online shopping link for Guitar Center takes you to Musicians Friend (or it did a while back) so there seems to be a lot of overlap. I just liked the way they were so much more easy to talk to than the other music stores. Very neophyte-consumer friendly.

TW

Dave Carlson
10-06-2005, 04:40 PM
Thanks for the info. I plan to use a Mackie (or equivalent) or the output from an automatic mixer (the applications are for a city council chambers and a distance education suite).

Since you all use Mackie's, have you run into any hum/buzz/RF interference problems? This has been a problem in the installed sound reinforcement world, but I'm not sure if it has affected this part of the universe.


I have an older 1202 that has very significant 60 cycle hum. It has a little bleed between the L & R channels. I have used another Mackie that had virtually no separation between L & R. I have used other Mackie's that were clean, and have talked to engineers that have taken both sides. If anyone has any idea where onboard the hum might be coming from, I would appreciate any info.

Dave

ssdcinc
10-06-2005, 06:43 PM
are you sure its not a "ground loop" Problem ?

...seen it many times before, many components cause
a hum and sometimes its can be removed using a "ground isolation
filter" (connect through you main rca inputs/etc) or sometimes even a
using a ground lift (3-prong to 2-prong) adapter on one of the
components work.

... at least this is the case with alot of DJ gear I use.

rnd
10-10-2005, 09:06 AM
The older Mackie consoles (prior to the VLZ series) had hum problems that were due to improper grounding (Pin 1 of the XLR jack was not properly grounded to chassis) of the pre-amp stage of the mixer. This was addressed in the VLZ series with a new pre-amp design and grounding scheme that was recommended by AES. You can overcome this by adding outboard input transformers or getting a new mixer. I think the new mixer would be less expensive.

georgew
05-26-2006, 10:36 AM
As previously mentioned, the main source of hum is improperly grounded equipment i/o.

The problem in equipment design is that balanced imputs are properly grounded when they use chassi ground, so that there are no ground currents on interconnected equipment plugged into the same ground source.

The problem comes from bad designs, broken or missing ground straps, and single-ended (unbalanced) equipment. In the single-ended world, signal ground is typically not chassi ground.

On my vt BOB, I can receive a clean signal, but I can't feed a clean signal. I can feed single ended equipment without much hum, but if I try to feed any balanced system, I get a 120hz hum. Well, I say 120hz, I'm not sure, but it is higher pitched than the normal 60hz hum.

So are the bob's signal grounds bonded to chassi ground? Or is this another case where the audio i/o is improperly designed? And what is this 120hz coming from? Is that a pc power supply issue or something?

Jim Capillo
05-26-2006, 04:57 PM
George, I'm not sure if this is your problem (I'm not an electrician), but years ago, I did a few shoots in a startup studio where the guys did their own electrical wiring for the studio lights. Seems they had a grounding problem with both legs of the 220 coming into the building and they had all sorts of hum problems with the audio. I think they had to redo the grounding throughout the whole building to fix the problem.

slx
05-28-2006, 03:50 PM
On my vt BOB, I can receive a clean signal, but I can't feed a clean signal. I can feed single ended equipment without much hum, but if I try to feed any balanced system, I get a 120hz hum. Well, I say 120hz, I'm not sure, but it is higher pitched than the normal 60hz hum.

So are the bob's signal grounds bonded to chassi ground? Or is this another case where the audio i/o is improperly designed? And what is this 120hz coming from? Is that a pc power supply issue or something?
Yes Toaster I/O is improperly designed. You have balanced I/O on BOB, but BOB is connected to VT card unbalanced. 120Hz hum is caused by rectifier in any power supply.

Pete Draves
05-29-2006, 08:14 AM
My system is veryclean.

No this is not a joke. I bypass the bob and use a external mixer.

The audio from the toaster to a jensen rca to rca isolation xfmr then to the mixer mic chanel Line in withgain set to a -10 level.

The input to the toaster uses another rca to rca isolation xfmr from the alternate out of the mixer to the mini jack in to the toaster.

ALL the computer hash and power supply noise is eliminated.

The outputs from the bob contain an amplified version of the noise that can not be filtered.

No filtration can be done between the bob and toaster due co common powersupply noise. If this were to be done it may require a "wall wort" isolated power supply. this would then have to have opto isolation for all of the control aps within the bob to reduce common mode noise.

The best I have come up with is to replace the audio of the bob with an external mixer as explained.

The system is clean, good for premastering the thousands of DVD's a year.

If any one needs a block diagram and parts sources please post and I will create drawings.
Pete

slx
05-29-2006, 01:02 PM
My system is veryclean.
No this is not a joke. I bypass the bob and use a external mixer.
Pete
Did you try put isolation xfmr between BOB and card? In my opinion the biggest problem is this unbalanced connection.

Pete Draves
05-29-2006, 02:59 PM
because of the circuitry in the bob you can not put any isolation between the bob and the toaster card. This is confirmed by newtek.

if you are using the outboard mixer, you bypass the bob, and run all with mixer.
This works!!

the unballanced out from the card and go into any mixer, the mixer will normal to the unballanced mode and work fine. you will have to up the gain for that stage to compensate for the -10 input.
Pete