connecting an outboard compressor

[jinglemaker]

Hi everyone!

This is my question, please don't laugh. I've got this incredible Danish all-tube compressor (Tubetech LCA 2B) with really exxelent sound (can't hear it, but you know it's there type of...) but I don't know how to connect it. I mean, I tried to use it as an aux/send, but the signal entering the compressor was too low (I followed the manual which says to connect an outboard device on outputs 3, 4, 5, 6... BUT: DIGI's outputs 3 and 4 (5 and 6...) are unballanced, and I have to lower the threshold and set the maximum compression to move the led meters on the Tubetech, which has ballanced ins/outs, just a bit). This way, I underuse all the headroom of the unit and it cannot perform the way it should.
Any suggestions would be very much appreciated, 'cos I'm seriously re-thinking my non-smoking decisions:=)

Thank you!

JingleMaker

[Swaphappy]

Try this,

If you have a mixer you could connect it through one of the channel inserts.
Or maybe between the direct out of the mixer and the input of the Digi 001.
If no mixer you may need a pre-amp unit.

[elijahsongs]

I think you're going to need an external pre-amp with an insert to properly utilize this compressor... Make sure it has inserts!

[Vastapol]

Don't question your non-smoking decision! I quit 2 years ago and made it thru a few crisis.... [img]images/icons/wink.gif[/img]
The problem with using an outboard comp(or any other effect) is that it will add 2 more conversions (D/A out and A/D in). I made a decision not to use any outboard stuff when mixing. Use the compressor only for tracking, you'll get better results with plug-in's, not to mention flexibility. Also, if you're using the services of a (reputable)mastering house, let them take care of the final comp/lim process.

[Stone Knife]

I gotta respectfully disagree with the above post. The TubeTech is probably better sounding than any plug could possibly hope to be.
It'd be a shame to not use it... I'd agree with the advice to use it while your audio is still analog.
Then only using it again if you must, while mixing down to say, 1" stereo tape. Hoo! Otherwise stay digital once digital if u can.
But for general use, using it while tracking or across the output buss of a good mixer- delicious.

[gerax]

To me there isn't anything wrong with using an analog outboard compressor with the rest of the digital setup: I do it quite often, and if set up properly the difference will be minimal, it obviously depends on the context of music you're using it in, I mean I won't certainly use it for classical or acoustic, where the effect of another D/A and A/D conversion would be more noticeable, but in a pop or rock context I'd certainly go for it.
If the signal you're sending out of the 001 is +4dbu it doesn't matter wether it's balanced or not ( as long as you don't run long cables, remember that all of the internal electronics in the professional equipment too are unbalanced, they get balanced when they have to travel outside the machine), so the loss of level shouldn't be an issue; I usually set up my outboard compressors like this: first of all create an insert path in the I/O setup and label it so it will pop up in the available insert options; if you dont want to compress the original signal duplicate the track and apply the compression to that, this will leave the original untouched and fully dynamic, while you'll have the compressed one on another channel and you could blend the two to taste. By putting the compressor in the insert path (and not in the auxiliary) you're sending all of the signal (serially) to the inserted device, so all of its level will be used (whilst with an auxiliary you send it in parallel and need to set the send level); You may notice a slight mismatch in time of the processed track (due to D/A and A/D conversion time), by a few samples, this can be corrected by sliding the track forward by a few samples to compensate the converters delay. One final suggestion: use the best cable and connectors you can for the inserts and sends, because the unbalanced signal will leave the machine and needs to travel on the best medium available to avoid degradation, keep lenght to 2 meters maximum.
This should work, at least it's working for me, but with such a cool compressor it's worth to give it a try (I found it expecially good for vocals, because you don't effectively hear it working, but the levels always stay put).

Hope this helps

L.G. [img]images/icons/smile.gif[/img]

[KaiXXX]

If the level is too low, make shure you have the PT Fader not lower than 0dB, actually you can boost the signal with the fader or use a plugin (trim plugin for example or a compressor plugin and only use make up gain). This should give you a decent output level. When going back to 001 check that the inputsensitivity is set correctly (+4dBu or maybe less).

Definitely consider the delay (as mentioned above)!

[jinglemaker]

Gee, thanx for your response, since now I didn't even bother myself with inserts... and the whole new world opened:=))(well, sort of).
But anyway (hope that Gerax reads this), regarding the outputs; I made this "test". I fed the compressor with the signal coming from the DIGI's main outpututs and the compressor performed really fine. Then I fed the same signal from outputs 3 and 4 and the level coming to compressor dropped significantly (for about 5, 6 db). I said to myself...if I want to hear the machine, why not connect the main ouputs to compressor inputs and then feed the compressed signal to DIGI's inputs 3 and 4. And the whole setup started to ring (loops and stuff of course). So, my problem in esssence remains; not having any input gain or signal preamplification option on my outboard compressor, I barely make it to compress about 5 db of the maximum signal coming from the DIGI. I can't make it to "squeeze" the signal more. Frustrating.
Any idea what I could do without having to use outboard mixing desk or somethin' similar to raise the signal level?

Thanx again! You're all great!

Jinglemaker

[gerax]

Jinglemaker

Obviously if you connect the compressor using the main outputs you're going to create a feedback loop, since the signal being sent out and compressed gets fed back again and agai and again... no way. In my opinion there are several things to do to get a healty signal to feed the compressor: first of all check out the effective level the track has been recorded at: if it's real low (remaining in the "green" zone of the meter even in its highest peaks) you cannot expect it to drive the compressor input efficiently without some help. You can boost some level by using some internal plugin (like Gain Audiosuite) to raise the level of the whole track, watch out for the maximum peak not to reach 0 dbFS or you're going to clip the signal, (so use the peak detection function before and then apply the boost as needed). Another plugin, as a compressor with all settings flat could be an alternative, but check if it doesn't change the sound, as each plugin has its own "signature"and you can hear it even when it's not working, but just plugged in the channel.
In the end there's only so much level you can boost before you actually worsen the signal to noise ratio (remember, when you boost volume you raise the noise level of the track too) and if you pass a noisy signal in a compressor the noise is going to be even worse due to the compressor's average signal level raising. If the track is so low it doesn't reach a nominal level to hit the front end of the compressor with a fairly high voltage I'd go with a plugin for the actual compression, but the sound you get is the actual reference you should judge upon.

Hope this helps, post back your results.

L.G. [img]images/icons/smile.gif[/img]

[jinglemaker]

Hi guys & gils!

Tried everything, I mean, I got the levells as hot as possible, my DIGI gain is set to 0,0 db, but I simply cannot get the compressor (my does not have any signal preamplification stage, you cannot raise or lower the input gain) to work with the signal coming from any other output than 1 and 2 (whidh is 6 db "hotter" than 3 and 4 e.t.c.). So, I raised the level with an outboard mixer. I know, this isn't a permanent solution, but nothing else worked.

Thanx anyway for your help!

Jinglemaker