chanceoperation wrote:The problem is that the signal out of the mixer's send is a tad weak for hitting the compressor where it works best.
This is quite a common issue as desks of this type tend to feature unbalanced inserts at a depressed operating level (usually somewhere between -6 and 0dBu) -- the lower insert level being necessary for valid internal technical reasons.
And this is compounded by some outboard which only starts to sound 'interesting' when pushed quite hard -- and the DMC is designed to handle signals up to a whopping +27dBu.
There are several possible options, although some may not be deemed practical:
The most obvious option is simply to run the source channel 10 or 12dB hotter than you are currently doing. The downside is reduced headroom in the input (and potentially EQ) stages of the desk, and you can probably get away with that, although it may be an issue depending on how and what you're recording.
Another relatively simple option, albeit expensive and requiring some DIY, would be to introduce a step-up transformer connected to the DMC input. That would balance the signal into the DMC and give the signal a useful uplift... But you'd need a couple of high quality transformers designed for high line levels and they won't be cheap, and you'd have to put them in a box and wire them up.
Next, you could put a line-level preamp in front of the DMC to boost the level by 10-12dB, but the downside is a more complex signal path and potentially more noise/distortion (or beneficial character, depending on your viewpoint).
And lastly, but probably not practical in your situation, a better technical solution, would be to modify the input stages of the DMC to make it more sensitive....
The GL2400 manual says it sends at 0dBu. It does not mention impedance.
Impedance really isn't an issue with line level signals. We are dealing with voltage transfer, so as long as the input impedance is more than 5-10 times higher than the source impedance, the precise value doesn't matter. Output impedances are almost always less than 150 Ohms, and input impedances always more than 10k Ohms, so there's never anything to worry about in that respect.
I am looking for a solution that:
- gives the compressor a slightly stronger signal,
- is adjustable/trimmable,
- is transparent,
- is either not overkill, or,
- offers my project studio some other useful features (for example, a good stereo pre-amp I can use elsewhere, if that applies to this use case too)
Personally, I think I'd run the channel hotter... Or change the desk for something more capable, or choose a more versatile compressor.