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« on: January 23, 2018, 11:55:56 PM »

 I have a vintage hhb radius 40 channel strip(yard sale find).I want to use it with my backup vintage YAESU 101and rice boxes on (AM)   Could  anyone give me some (ball park ) settings for the compressor section  (1) Attack time (2) Release time (3) Threshold 4 ( Ratio )  Grin THANKS AM FAMILY Grin

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« Reply #1 on: January 25, 2018, 05:00:04 PM »

Ooookaaay, I know you've already heard this, but I'm going to try to inspire some discussion here...

Like most studio processors, yours has the compressor before the EQ. For transmitting, the opposite is needed. I'm not familiar with the Radius 40 although it looks like the "EQ Pre" button does this. That's very important.

I recommend using the EQ to add a bit of presence frequency boost (HM 3k5 and HF 5k both with +6 dB of gain). LF and LM can be left with 0 gain.

The compressor will need to address peaks, so Attack and Release should be "fast" and Ratio on 1:30. The Threshold control should be set to give you 5-8 dB of gain reduction on voice peaks.

These settings will give you a bright, crisp sound with voice peaks in check. The limited amount of gain reduction will keep the audio punchy but not "mashed up".

Nice unit!
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« Reply #2 on: January 26, 2018, 08:30:58 AM »

Thanks for sharing these starting points. I have a Behringer DEQ2496 that I've been thinking of using and the compression settings have been something that I've been doing a lot of searches on. Seems everyone has their own recipe. Your audio sounds great, so I'm assuming you use similar to what you described. The other reason that I'm thinking of using the 2496 is to brighten up a ribbon mic that I have. Plenty of low's but it's really lacking the "brilliance". This might be the foundation for this weekend's project.

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« Reply #3 on: January 26, 2018, 09:27:53 AM »

Hey, thanks! This topic is about as subjective as it can get, particularly with equalization. Many ops like having a "signature sound", which is great, as long as the basics are taken care of first.

The top priority is peak control and most processor attack times are too slow for this, but everything helps, and that's why I suggest "fastest possible". If a true limiter or clipper can be placed right before the transmitter then there's a lot more flexibility.

A 30:1 (or infinity to 1) compression ratio is also necessary for limiting and as long as the gain reduction is kept reasonable and not driven too hard. The sound is clean, open, and controlled.

The next priority is pre-emphasizing (boosting) the presence frequencies. I use a parallel cap and resistor. This is important because our ears are most sensitive to these frequencies and receivers tend to roll them off. You can gain a lot of effective loudness simply by boosting the 2-5 kHz range. I don't use any other EQ.

Stereo (two channel) studio compressors are quite popular because of their low cost and availability. These can be set up with one channel handling average gain control (low ratio) to keep modulation levels consistent while the other channel is set for high ratio for peak control. The key is to disable the gain buss that ties the channels together. This function is needed for stereo music processing to preserve the stereo image but absolutely should be disabled for our purposes. There's usually a switch marked "stereo/dual mono" or something like that. Dual mono is critical.

Most studio processors that have both compression and EQ (Symetrix 528 for example) have the equalizer after the compressor. This is great for studio work yet completely unacceptable for modulation control. Fortunately, many have insert jacks on the back that allow users to reverse this order.

Oh, and your ribbon mic... those typically have profound "proximity effect" which is a sensitivity to low frequencies when you speak close to them. Try backing off 6-8" and I'm sure you'll notice an improvement.
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