Harris Tri-Band MSP-90 help needed

I've just joined this group a few minutes ago, but, other than this, I find no way to post a new thread. I'm trying to connect a Harris Tri-Band MSP-90. I need to know how to connect the audio input and output. I'm not an engineer, but a deejay working in a home studio. We record the show here, then it's played at the station.

Thanks,

Doug Fields said:

I've just joined this group a few minutes ago, but, other than this, I find no way to post a new thread. I'm trying to connect a Harris Tri-Band MSP-90. I need to know how to connect the audio input and output. I'm not an engineer, but a deejay working in a home studio. We record the show here, then it's played at the station.

Thanks,

Click to expand...

That's a really old device (and not particularly good from an audio perspective), but as I recall the inputs and outputs are clearly labeled on the rear of the unit. There should be a screw barrier strip on the back.

What are you trying to connect this thing too? As in; what's feeding it, and where is the output of it going to?

Well, they aren't labeled in a way that I'm accustomed. I've since figured it out though... Yes, it's dated 1980. I like the sound of it, for music, but I was going to use it as a voice processor. However, I've found this unit is not conducive for such an application. I'm just going to purchase a dbx 286 instead. I'm on a shoe-string budget, and I was trying to run my XLR mic into it, and then into my audio mixer. It isn't a broadcast board.. it's just a little Radio Shack mixer. I had tried various ways of connecting it.. all with unsatisfactory results. I have a pretty weak voice, and was trying to beef it up a bit. I'm trying to do an oldies show. We're going to VT it here, upload it to the stations cloud, then they'll download it and play it on the air.

Got it, okay thanks. The MSP-90 was originally designed as a multiband audio processor for (mainly) FM stations. There were two versions; single channel and stereo. The device is 600 ohms +4db line level in and out. As you've discovered, connecting a mic directly into the MSP90 won't work because a mic is typically 5,000-15,000 ohms -50db mic level out. The only way you could use this with a Radio Shack mixer, would be to connect the MSP90 at the output of the mixer and jack up the input of the MSP90 high enough to do some processing. As with most consumer devices, keep in mind that your mixer outputs -10db at 0VU, where as mentioned; the MSP90 is designed for +4db at 0VU.

Now something about the MSP90: The rub against the Harris MSP 90 back in the day, was the lack of decent peak control and it had a pretty poor signal to noise ratio (hiss) as compared with competing processors. Fast forward thirty years, and several of the old capacitors inside that MSP 90 have dried-up, degrading performance even more.

I'm certainly not suggesting you don't have fun playing around with the device and electronics in general. I completely encourage it. It's just that if you're serious with trying to produce something for radio, a podcast, web stream, etc., that you may be disappointed with the end result by using the MSP-90 as a voice processor. As you've already discovered, there are much better choices which already include good microphone preamps from DBX, which will get you closer to a clean, processed sound.

Good luck!

This is the single version. I'd used it years ago in my home stereo system through the tape monitor. Loved the sound. My co-host and I are using separate mic's, but the same "board". I had attempted to run my mic (XLR) into a separate preamp, and then into the mixer. That didn't work either. And with the other preamp involved.. it was even more noisy than usual. I'm just going to try the DBX 286S. My co-host has a loud, booming voice. Mine.. is pretty weak and wimpy. Sadly...

As the popularity of the Dorrough DAP-310 was overcome by Optimod, Gregg Labs, Aphex, Pacific Labs and CRL processors, I found a number of cases where it was repurposed as a mic processor. About the only modifications I would see in those boxes were the removal of the clipper card (or lowering the level beneath the clipper's threshold), and possibly some changes in the simple r/c networks that controlled compressor release. Being gated, with a center-of-range return, it did seem to have a positive effect in the airchain.

However, whether the DAP was actually a good voice processor is, like all other discussions like this, subjective, and something I was never in a position to evaluate first-hand.

These boxes didn't have the adjustable equalization / downward expansion range, sibilance reduction and preamps, found in actual mic processors, being designed for a different purpose.

Maybe a rough comparison could be continuing to insist a dial phone was good enough after the world moved on to touch tone. Sure, you could make a call, but how would you "press pound for more options"?