ULTRA NEW TO VOODOO WITH LEGIT QUESTIONS.

Hookin up those Audio Boxes without gettin yourself Perplexed.
kf6phx
Voodoo Audio Head
Posts: 14
Joined: Sun May 01, 2011 5:42 pm

Post by kf6phx »

another crazy question...is the output of the xenyx 1002fx mixer(unbalanced) ok to run into the acc1 plug into the back of the icom 756 pro 3 or do i have to have an ibox running into the front of the radio?

SawzAll
Voodoo Audiophile
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Joined: Fri Jun 25, 2010 4:22 pm

Post by SawzAll »

kf6phx wrote:i appreciate the input..very good advice which is what i need right now.almost wanted to throw in the towel on this gig after only a month of playing with this. a question though...ive read that its best to go:
mic>mic2200>mdx2600(light noise gate,light compression)>eq>mdx2600(final compression,limiter)>mixer(which im using for audio from computer and for recording into computer).

so whats the question? what are some good starting settings for light compression in channnel 1 then settings for final compression in channel 2?

thx again.
The noise gate should be the last device in the chain - IMO.
Broadcast compression settings are different from live sound or recording usage, as these are my areas of expertise. Setting up the compressor as a limiter is a great place to start, as most broadcast stations use a compressor/limiter for the final output.

mic>mic2200>EQ>comp/limiter>gate>radio

if you are getting frustrated; then just start out with the mic and preamp. Then, get with the EQ. After you get that one to your liking and can verify with another station for sounding right; then set the compressor with limiter settings:
"1) Set your input level correctly, so there is no distortion and plenty of
headroom.

2) Start with ratio about halfway. Turn down threshhold so that it just starts
to have an effect on the signal.

3) In most cases, set the attack and release to their fastest positions.

4) For more limiting, sneak the threshhold down a bit and the ratio up a bit.

5) Set your output level so that it is roughly equal to the input level when
bypassed."
Don't go to crazy with the threshold settings. You just want it to affect the peaks; not average speech. This keeps the dynamics alive w/o killing the audio and make it sound like it is 'pumping'. Too much compression/limiting will also affect the EQ - not desirable! Ultimately, the uniformity of the output shouldn't sound 'canned'. Ratio should be about 4:1; maybe a little more.

Doing the gate should be intuitive enough - I think . . .

kf6phx
Voodoo Audio Head
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Joined: Sun May 01, 2011 5:42 pm

Post by kf6phx »

so...so im not a total retard here...what kind of signaling should i be seeing on the mdx2600 metering to know the compression is looking good? i know how the gating works...thats easy enough. im currently running 3:1 compression with the threshold at around -10. attack and release at almost completely lowest levels. i thknk what im trying to understand is where the compression should be and what exactly the threshold is doing. i can hear the change in audio as i adjust the threshold...just not sure how it should look on the meter on the unit. also i keep hearing not to run the compressor on the radio itself....but when i hit the comp wide on the icom756 pro 3 people saying it adds more bandwidth so to speak to the audio. are my or their ears playing tricks on ourselves?

SawzAll
Voodoo Audiophile
Posts: 66
Joined: Fri Jun 25, 2010 4:22 pm

Post by SawzAll »

kf6phx wrote:so...so im not a total retard here...what kind of signaling should i be seeing on the mdx2600 metering to know the compression is looking good? i know how the gating works...thats easy enough. im currently running 3:1 compression with the threshold at around -10. attack and release at almost completely lowest levels. i thknk what im trying to understand is where the compression should be and what exactly the threshold is doing. i can hear the change in audio as i adjust the threshold...just not sure how it should look on the meter on the unit. also i keep hearing not to run the compressor on the radio itself....but when i hit the comp wide on the icom756 pro 3 people saying it adds more bandwidth so to speak to the audio. are my or their ears playing tricks on ourselves?
The more the threshold is lowered; the more the signal will be compressed.
You don't want a lot of compression; not when the ratio is 4:1 or more. Just keep the threshold high enough to just compress the audio peak levels. Otherwise, all of the audio gets compressed and it will sound like it is 'pumping' when you speak. It will also have a 'canned' type of sound; which is very unnatural sounding. At this point, it has affected the EQ adversely.

Yes; the processor/compressor in the radio should be 'off'.

If you don't turn up the output on the comp/limiter to the same level as the comp/limiter is when it is out of line/once compression takes hold; then there will be a loss of output. You have to turn the output of the compressor up to match the level before compression.
From my last/above post:
""5) Set your output level so that it is roughly equal to the input level when
bypassed." "
See?

A decent compressor will have decent quality op amps. They need to be. Because if any self-noise is in the op amps when compression has been turned on AND the output turned up; it will bring the noise level up to the signal level. Poor quality compressors should be avoided for that reason! Or; too much compression/low threshold levels should be avoided - as this will bring up the noise level in any compressor.

Remember: A compressor can make a weaker signal louder, and at the same time - make a strong signal weaker.
That is why we only want it high enough to affect just the PEAK levels . . .

Avoid going into the front mic plug. There are caps in there that will filter out a great deal of what you are trying to bring into the radio. Going through the ACC2 port is highly recommended, as this bypasses the radio's native mic preamp and will enter the balanced modulator directly. In effect, you have brought your own preamp into the radio and done away with the radio's own restrictions to audio frequency response.

kf6phx
Voodoo Audio Head
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Post by kf6phx »

i like your style of explanation and it is greatly appreciated. i have the mic2200 ordered and on the way and ma planning on making all new starquad xlr's to keep the system balanced all the way until the output of the mixer which is unbalanced anyway and should feed the acc1 port directly in the back of the icom. sound like a winner?

SawzAll
Voodoo Audiophile
Posts: 66
Joined: Fri Jun 25, 2010 4:22 pm

Post by SawzAll »

Sounds like you are on the right track to me.

One other thing . . .
Using ferrite beads on EACH cable in the chain is a necessity - IMO. I run a 100w or less; but still RF was leaking into the sound chain. I use Mogami cable to boot; so it wasn't the cable's fault When I put them on (about $2 a pop), it really came alive and many unsolved audio dilemmas disappeared. Even between the cable out of the audio chain and into the back of the ACC2 plug got one. The mic to the preamp too. You will be glad you did this - IMO. If you run power; you might need to double up. Can't say; I'll let someone else address that one.

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Post by Voodoo Guru »

Ferrite is our friend...

We will love him and pet him and keep him as our own.....
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kf6phx
Voodoo Audio Head
Posts: 14
Joined: Sun May 01, 2011 5:42 pm

Post by kf6phx »

so what i was asking earlier was on the compressor when im adjusting it what exactly i was looking for on the gain reduction meter....if anything. when i watch you tube videos on compressor setups it seems that your adjusting so your seeing what i would term as "backswing" so to speak on the gain reduction meter of a couple bars. should the gain reduction on the meter match the output level meter? i know that a lot of it is listening to the monitor as well but im sure im looking for something specific on the meters as well. each day brings me newer understanding of what and how these pieces of equipment work with each other. you guys are awesome. thx again.

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