Audio DSP devices/speakers, etc?

[iMONITOR]

I've been looking over numerous audio DSP and Equalizer devices and/or speakers that claim to improve the clarity of sound from radio transceivers/receivers. They are supposed to improve the sound you want to hear while filtering out the sound/noise you don't want to hear.

Some of manufactures of such devices are Heil Sound, Ameritron, BHI Ltd., West Mountain Radio, MFJ, Timewave, SOTAbeams, ISP Technologies.

I'd be interested in hearing from any of you who are using or have used any of these devices and what your observations were, both good and bad.

Thanks!

 

[AK9R]

This is my opinion.

If the box truly has Digital Signal Processing, then it might help. However, many ham radio HF transceivers these days do DSP in the IF stage which makes me wonder if DSP in the AF stage is worth the money.

The generally accepted audio frequency range for radio communications is 300-3000 Hz. Sharp audio filters which roll off frequencies above or below that range may help. But, then again, many ham radio HF transceivers already have "tone" controls built into their receivers, so why spend money on an outboard box? Some of these boxes have a "parametric" filter which allows you to notch out a range of frequencies and slide that notch up and down the audio spectrum.

BHI ParaPro EQ20 has high and low filters that can be frequency adjusted, but no mid-range control.
Heil PRASEQ has a "mid" filter that can be frequency adjusted plus it has high and low cut-off filters.
MFJ-616 is a four frequency equalizer. The frequencies are fixed.
Timewave DSP-599zx has high and low filters that can be frequency adjusted, but no mid-range control.
West Mountain Radio CLRdsp has a "tone" control. It may just be a high frequency control or it may adjust highs and lows simultaneously.
I didn't look at the others.

Of the above-listed products, the Heil PRASEQ might be the best choice if your radio already has IF DSP. If you are looking to add DSP functions to an older radio, the Timewave DSP-599zx might be the best choice.

I own none of these products. My HF radio has built-in DSP noise reduction, notch filters, and noise blanker and built-in receive tone controls.

 

[iMONITOR]

From all the demos and reviews I've watched they seem to be nothing more than a glorified tone controls and they don't do much to eliminated actually noise and interference.

 

[RFI-EMI-GUY]

Timewave DSP599zx. Nope, not a "glorified tone control". A brick wall audio filter with beat tone elimination and other features. I have one and it is very versatile. I have even used to post process, to clean up old analog Inmarsat downlink audio that was originally poor signal, wrong bandwidth, compandered. The source was from a cheap cassette recorder, through the DSP599zx and onto a digital recorder. It does what it advertises, very well.

 

[iMONITOR]

Timewave DSP599zx. Nope, not a "glorified tone control". A brick wall audio filter with beat tone elimination and other features. I have one and it is very versatile. I have even used to post process, to clean up old analog Inmarsat downlink audio that was originally poor signal, wrong bandwidth, compandered. The source was from a cheap cassette recorder, through the DSP599zx and onto a digital recorder. It does what it advertises, very well.

What dealers stock/sell this? I'm not finding it anywhere other than Ebay.

 

[RFI-EMI-GUY]

What dealers stock/sell this? I'm not finding it anywhere other than Ebay.

I think AEA bought Timewave and the DSP599dx is now out of production. Best to look for ham estate sales . I got mine hardly used for $175 when they were still getting over $350 used. You might check e-bay. They are still getting a good price. But I see one that might be a bargain.

TIMEWAVE DSP-599zx Digital Noise Filter

Support here it appears.

TIMEWAVE DSP-599zx Digital Noise Filter

 

[AK9R]

What dealers stock/sell this?

According to the Timewave website, it's been discontinued.

 

[prcguy]

From all the demos and reviews I've watched they seem to be nothing more than a glorified tone controls and they don't do much to eliminated actually noise and interference.

I've used some of the BHI products and its like magic, noise gone, heterodynes gone, recovered audio very good. I have an old Timewave DSP-9+ that I got very late in the game after I parted with all my analog receivers but it does a decent job of noise reduction wtihout mucking up the audio too much. Probably the best DSP noise reduction I've used is in my Elecraft K3 radio, I never use RF gain any more and just leave the DSP on. Its very transparent and gets rid of 90% of the noise.

 

[slowmover]

West Mountain CLR-SPKR - Review

 

[SA4MDN]

i have 2 BHI DSPKR,s and 1 Duel-Inline and cant fault them, the DSPKR,s are on my 2 TS-850,s and the Duel Inline is used om my TS-830,