Noise on Master outs

I'm mixing this project and am reamping / mixing through a board.
signal path is as follows.

Coming out of the individual outs on the back of a BLA modded 002 - into the line inputs on the boards'channels-fader on board is at 0- input gains are turned up to about 3 oclock ( -55 -60dB) and the meters barely jump- no pads on - i mix it- itvsounds wonderful off of the monitor channel on the board- get it as loud as i can without clipping and rerecord the 2 mix into ch 1 and 2 of the 002. Everything is sounding soooo good.

I then switch the monitor back to out of the 002 and i hear this ugly grindy warm hum on playback. Once the music is playing, the hum is hidden, but at soft points the hum is clear.


Anyone ever had an issue like g his before?

Capacitor issue maybe?

Thanks in advance.


The inputs sound great. Very clear.

Does not compute - what is a BLA modded 002?

Jakob E.

BLA = Black Lion Audio , a company in Chicago that does mods on consumer gear. They seemed to be cool folks when I talked with them.

They've since been sold to some big company or something since I last was in contact. 

To my understanding, the individual channel outs on the 002 are supposed to send line level. It's this that makes me wonder about all the gain needed .

ReRibbon said:

To my understanding, the individual channel outs on the 002 are supposed to send line level. It's this that makes me wonder about all the gain needed .

Click to expand...

Me too. Looks like there is something wring with the audio connection from the 002 to the mixer line input or with the 002 itself.

Cheers

Ian

I know the outs on the 002 are working perfectly fine with other applications.  Must be the boards line in (s). All of them though?

But that cant be though, because I tested them all before doing the mixing.

I wonder if it's some kind of RF thing but without anything being broadcast.

The mixer was sitting  about 8 inches above the racked 002. Above the 002 and under the board, there is a multi power strip box. I wonder if that had anything to do with it.

ReRibbon said:

Coming out of the individual outs on the back of a BLA modded 002 - into the line inputs on the boards'channels

Click to expand...

Mixer's brand & model, please... Are the connections balanced?

Yes Sir, the mixer is an obscure British thing called The Location Mixer. They were supposed to have been made in the late 70's-early 80's.

Although its probably not some high dollar board, tonally, it sounds really great. It's thick like a Neve and clear and up front like an API. A friend of mine was really impressed with how it glues the tracks together. 

it's a cool little board and I would like to get it back up to tip top if possible.

the manual says in regards to the insert, that "the stereo jack socket is provided for inserting special devices Pre equalizer into the channel. effects modules such as a limiter or compressor are good examples. the insert point may also be used as a direct output for the channel which is useful for supplying individual tracks to a tape machine, or any other external source. "

I want to use the direct output function and if possible,  I'd like to use it for tracking and mixing. .

Balanced?
it states
tip-  output level 0 dBm
ring - return output resistance 68k sleeve - ground input resistance 40k

The board has 2 output transformers and input transformers on every channel. Belclere 8260 's. They sound awesome,  but no one has ever heard of them...

ReRibbon said:

Balanced?
it states
tip-  output level 0 dBm
ring - return output resistance 68k sleeve - ground input resistance 40k

Click to expand...

I don't understand. You said earlier that you need to crank the gain at about 55dB.
Now you say you connect it to the inserts...
If you return the signal from the 002 into the inserts (that are indeed unbalanced) how are you de-balancing these outputs?
I'm not sure about the output design of the 002, but if they are floating, you must connect the cold leg to ground, preferrably at the mixer side.
If not floating the cold leg must be disconnected at the 002 side.
The Digidesign site is useless about this.

BTW, the insert specs make just about no sense .

I thought you said you were feeding the 002 into the line ins of the mixer - I don't understand what you are doing with the inserts?

Cheers

ian

sorry for any confusion. After rereading and thinkg about this mess, id like to try to do this. Maybe it will fix the issue of the master bus noise for reamping.

What I'd like to do, is to use the mic pRes going transformers only and straight out off of the insert jack. That's why i referred to the insert.

In regards to th e master outs, arnybthoughts on the noise?  Will try ton post a clip in a minute here.

here is a clip of this hum that I 'm hearing.

https://soundcloud.com/poiu-2/hum

I am confused by what your doing.... the outputs of the 002 is balanced and on a trs jack.  That should go into the line inputs on your mixer.  Are you sure that the line inputs on the mixer are balanced? Are you sure you are not creating a ground loop between the two devices?

I am also confused about having to add 55-60dB of gain on the line inputs. ideally if you are going line in from a line level device the preamp gain would not be necessary. 

Ok, so there are two issues thing I'm talking about...

1. Finding the cause and solution to the noise / RF coming off the master buss.
and
2. Figuring out how to use the insert as a simultaneous direct out while having something plugged into either the mic/line input without anything in the signal being automatically muted by using the two at the same time. 

Plug it in half way? TRS connector with the tip and slave shorted? If the insert is balanced you need something more special, like a cable with 3 TRS (or XLR) in parallel, just like christmas tree lights.

JS

ReRibbon said:

2. Figuring out how to use the insert as a simultaneous direct out while having something plugged into either the mic/line input without anything in the signal being automatically muted by using the two at the same time.

Click to expand...

That one is easy. Use a cable with a TRS jack, with tip and ring shorted; that way the signal is available to the external world and the internal connection is re-established.

ReRibbon said:

1. Finding the cause and solution to the noise / RF coming off the master buss. *

Click to expand...

You must proceed with the generic faultfinding process. Using preferrably the headphones (if it exists), start by connecting each signal in turn. Does the noise appears all of a sudden or progressively with the number of sources? Does one source stands out as the main contributor?

* You'll be chastized by JR for wrong spelling of plural bus.