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Reviews Categories | Filters, Audio: (DSP and others) | West Mountain Radio CLRdsp Help

Reviews Summary for West Mountain Radio CLRdsp
West Mountain Radio CLRdsp Reviews: 31 Average rating: 4.7/5 MSRP: $219.95
Description: Outboard DSP with internal 4 watt audio amplifier for use with your station speaker.
Product is in production.
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KE4EVL Rating: 5/5 Feb 11, 2018 06:19 Send this review to a friend
Great Addition - Huge Improvement  Time owned: 0 to 3 months
I recently upgraded to the IC-7300 from an IC-718 and I could go on and on about the improvements in filtering and etc.; however, I was still fatigued by the background noise and etc.. even with the great filtering. I decided to buy the West Mountain Radio CLRdsp... the best $199 addition to this station. Just plug it in and it works. You can hear the noise floor lowering. I use it with the Filter knob the 9 O'clock to 12 O'clock knob position for best results. Too much and it sounds like a and aquarium bubbling (which is still better than the noise I would say). I can adjust the tone control with the IC-7300 filtering and get a great sound. I can actually pull some audio out of the noise floor so it is intelligible whereas without, I could hear it with all the noise, but could not understand it. I highly recommend this to anyone struggling with the noise.
KE0Q Rating: 5/5 Nov 12, 2016 11:33 Send this review to a friend
Works Well!  Time owned: 0 to 3 months
Received a new ClearSpeech DSP Unit, Model WMT-58407-949 yesterday from DX-Engineering. I've used it on 40, 20 and 17 with my Kenwood TS-480SAT and it has worked very well. I never liked the DSP in the TS-480 but the DlearSpeech DSP has made a great improvement, especially in the evening when there's a lot of noise. It's sure much more pleasant to the ears on 40 meters.
K2CJB Rating: 2/5 Nov 11, 2016 20:04 Send this review to a friend
VERY disappointed!!  Time owned: more than 12 months
I purchased it a few years ago. It worked for about a year, then just output a loud buzz. Contacted West Mountain. They had me ship it back for a repair (with a charge since it was out of warranty). That was just over a year ago. Now it suddenly started outputting a loud buzz during RTTY or BPSK transmit. I've contacted them again to see what I have to do now.

Very disappointed. It's failed twice.
MM3IDR Rating: 5/5 Sep 25, 2016 03:21 Send this review to a friend
That's what I wanted!!!!!  Time owned: 0 to 3 months
Previously using a competitor outboard speaker with DSP, which has all of the buttons in very much the wrong places. It is tedious beyond belief and the functionality is a little questionable.

This device is fantastic. Ergonomically perfect, all the knobs are nice to use and easily accessible. The DSP just works, I don't need to bang on about that, because it does, just work - properly.

I'd recommend it very highly indeed, an asset to any station.
AC6BW Rating: 5/5 Sep 15, 2016 20:58 Send this review to a friend
Excellent DSP Filter  Time owned: 0 to 3 months
Not much more I can say beyond what's already been written. I'll add a couple of points. This is an excellent standalone DSP filter, and has exceeded my expectations. I run a FT-450D, and the built-in DNR is a little lacking. It tends to distort the desired audio signal too much. The WMR CLRdsp works much better. I usually operate with the Filter set to about the 9 O'Clock position, sometime a bit more. One comment about CW operation. I noticed that the DSP filter was actually filtering my radio's CW audio sidetone while I was transmitting, and needless to say, this made it very difficult to send CW. I called WMR, and they suggested increasing the volume of my radio's CW sidetone. I tried this, and it worked! They explained that it's all about SNR. If the sidetone volume is too low, the DSP filter detects the sidetone as noise, and filters it. I got excellent support from WMR!
I found that this filter can sometimes allow me to copy weak signals that would otherwise be unreadable. I found that out tonight while working A5A in Bhutan on CW. I highly recommend this filter.
K2JF Rating: 5/5 Aug 24, 2016 14:56 Send this review to a friend
Hard to believe  Time owned: 0 to 3 months
I have a Icom Pro III with DSP I always liked. But I started to feel fatigued on CW with the background roar even with the DSP turned on. I thought I would give this a try and based that on the reviews I read here. I plugged it in, waited a while for it to set itself and found myself doubting how well it was working. I kept unplugging it and plugging the headphones again into the rig and the difference was very noticeable. It just makes listening so much less tiring.
WR3V Rating: 5/5 Feb 7, 2016 12:02 Send this review to a friend
Kudos  Time owned: 0 to 3 months
Noise on the bands/declining sun spots equal less operating enjoyment. I tried going after this from the rf side with little luck. (tried an ANC-4, didn't help my particular problem). So, I thought to go after it from the af side. I looked at the options, Gap or West Mountain, and decided to try the CLRdsp brick. Guess what, it works. If I had a $4000 radio, maybe that would have helped, but I don't. I have a $700 FT-450D that otherwise suits my purposes just fine. This is the best $200 I have spent on this hobby in a long time. Look at the K6BRN review earlier in this post for tips on using this little jem to its max. (BTW, thanks K6BRN)
N0XAX Rating: 5/5 Jan 3, 2016 21:55 Send this review to a friend
Very Nice External DSP  Time owned: 0 to 3 months
Just purchased this unit from DX Engineering. It was easy to connect, and very easy to setup. It is an adaptive type dsp unit. It seems the longer I am on a frequency, the better it works. Like another reviewer stated, if you change a setting, you have to wait for it to stabilize. I'm using it on my Yaesu FT 840, and it has made my ssb audio much less noisy. It's nice not having to listen to the backround static. Great product!
N7DK Rating: 5/5 Oct 26, 2015 06:33 Send this review to a friend
Big improvement to receive audio  Time owned: 0 to 3 months
This unit (the latest 3-knob model with tone control) is the best accessory I've bought in the past 10 years.

I have an old Kenwood TS-940 and a TenTec Omni VII. The Omni is more capable in almost every respect except one -- receive audio. The Kenwood is much more pleasant to listen to for extended periods.

The "whooshing" and "roaring" of digitally filtered receive audio on the Omni is really fatiguing to listen to. It sounds like air rushing through a tube, and after a while it gets really annoying. (I've read similar complaints about the K3 being terrific in most respects except receive audio.)

On the Omni, I fiddle with the settings endlessly, shifting the passband width and center frequency, sometimes just to change the nature of that annoying noise for a while. It helps, but not for long.

Right in the middle of the 2015 CQWW SSB contest, I scoured the net for something that might do better, and I came across K6BRN's review of the CLRdsp unit. My local HRO had it in stock, and I installed it and started using it in the contest. It took a little trial-and-error to use it most effectively, but now I love that little thing ...

I could add a lot more, but K6BRN's review has most everything important. In particular, be sure to follow his advice on feeding a high-enough audio level to the device -- just below the "clip" level. Otherwise you'll likely get a new set of filtering artifacts that sound like birds trying to chirp under water.

Now I'd rather listen on the Omni than the Kenwood. If you find that underlying noise "roar" annoying, you might try this device as well.

I'd be glad to talk to others via email about their experience with these nifty devices.

My compliments to West Mountain Radio!
K6BRN Rating: 5/5 Aug 6, 2015 13:39 Send this review to a friend
Great upgrade to an older radio, does exactly what it promises  Time owned: 0 to 3 months
This review is for the West Mountain Radio CLRdsp ClearSpeech® DSP Noise Reduction Processor, model number #58407-949. Several versions of this small unit have been sold over the years, with significant enhancements made to each revision. For example, earlier units had a selector switch to allow just a few levels of noise reduction, while later versions have a continuously variable knob that appears to seamlessly cover a broad range of noise reduction levels. Later versions also added a surprisingly useful tone control that earlier versions lack, and an on/off volume control knob.

BTW - I am primarily an SSB voice user and rarely use CW, but do work digital modes as well. My CLRdsp is the mid-2015 three-knob standalone version (no included speaker, Filter, Tone, On/Off Volume controls on the front panel).

I recently purchased this unit as an add-on audio only (baseband) DSP processor to enhance my aging Kenwood TS-440SAT HF transceiver, in fixed station use. At this time, the 20 to 80 meter bands are pretty noisy, and I live in a tightly packed seaside town loaded with plenty of man-made QRN (many damp and salt caked arcing 3-phase power lines) and QRM (fellow Amateurs) sources. After spending some time with a new Yaesu FT DX-3000, I was impressed with how quiet and fatigue-free its receiver seemed, particularly when DSP noise reduction was engaged. The triple conversion receiver in my old TS-440SAT is quite good and I have installed the optional 1.8 Khz and 500 Hz 2nd IF filters – but its audio can still be fatiguing to listen to for long periods, especially during noisy conditions. The Kenwood has some other interference mitigation features, including a very effective IF shift control, noise blanker and notch filter. How would they play when coupled with the CLRdsp? Very well, as it turned out. And there are some lessons learned I’d like to pass on.

I connected the TS-440SAT to the CLRdsp unit via the rig’s external speaker (high level) output using the jumper cable supplied, attached the CLRdsp to a salvaged hi-fi speaker and then wired the CLRdsp into a 12 volt power supply using the included cable.

My first discovery was that it’s VERY important to properly “load” the CLRdsp input level (i.e. A/D converter). If the input level is too low, noise reduction is less effective and DSP artifacts, i.e. “the underwater voice” effect, are pronounced. Too high and the CLRdsp begins to clip (and distort) audio, indicated by the normally green CLIP led on the front panel flickering red. In most cases, best results were obtained by: 1. Setting the noise reduction knob fully counter-clockwise (i.e. to minimum), 2. Turning up the rig’s volume control until the CLRdsp CLIP led just begins to flicker red, 3. Backing the rig’s volume off slightly to eliminate the red flicker, then 4. Setting noise reduction to the desired level. This loading adjustment is actually fast and easy, but is NOT detailed anywhere in the very short and inadequate CLRdsp manual. The loading level should be adjusted whenever the noise or signal level changes dramatically – i.e. when changing bands or when a new and powerful signal booms in. The right rig volume setting is also affected by the level of noise reduction set on the CLRdsp; lower levels of noise reduction will cause the CLIP led to light at lower rig volume levels – higher levels of noise reduction seem to allow higher levels of loading. So some “fiddling” can help optimize results.

My next discovery was how (well) the TONE control worked in combination with my rig’s IF Shift control. When the IF shift is adjusted to avoid strong adjacent signals, audio tonal balance changes, emphasizing either the bass or treble elements of speech. This can be very annoying. The CLRdsp’s TONE control really helped to restore tonal balance and I found myself using this control in combination with very slight tweaks to the TS-440SAT’s IF Shift even when there was no interference, simply to achieve improved audio quality.

The CLRdsp put out plenty of audio into every 8 and 4 ohm speaker I tried, and its own integrated volume control is very convenient. It had significantly more “punch” than the TS-440SAT had by itself. I finally settled on a very old Bose 201 speaker I saved from the scrap heap – it was not a very good AV speaker, but it made a great match to the CLRdsp as a rig speaker. I also used the CLRdsp with headphones with very good results. The CLRdsp has a separate headphone output jack that mutes the speaker output when in use and it can be set to accept either stereo of mono headphones, using an internal jumper.

Finally, the CLRdsp requires from five to 30 seconds to fully adapt to the noise and interference environment – and it continues to adapt as long as it is on. Each time the level of DSP noise reduction is manually adjusted, its best to pause for a while to see how the DSP filters settle in to the new level. During the settling period, the noise/interference level may be higher and there may be more voice distortion than when it reaches a (somewhat) “steady state”.

Once the CLRdsp was connected and adjusted as described above, I used it on 20, 40 and 80 meter SSB with great results. Background static was usually heavily suppressed (sometimes eliminated) with minimal impact on voice quality, and interfering tones were simply gone. My noisy TS-440SAT receiver became very quiet and pleasant to listen to – remarkable. Most interesting, the CLRdsp sometimes helped me pull SSB voice signals out of the noise, when I could not do so by (my) ear alone. In these cases, correct input level setting to the CLRdsp unit seemed more critical – I had to “fiddle” with it a bit.

Out of curiosity, I tuned in to some European AM broadcast stations on 40 meters in LSB mode, with TS-440SAT filter selection manually set to WIDE (about 6 KHz). The CLRdsp faithfully suppressed the AM carrier beat and use of the TONE and my rigs tuning/IF Shift controls to adjust audio characteristics made listening more pleasant in SSB mode than in straight use of the TS-440SAT’s AM mode. Very nice.

In summary, the CLRdsp unit is well made and does exactly what it advertises, dramatically suppressing interfering tones and random noise, once its adjustment has been mastered. And my faithful but decades old Kenwood TS-440SAT now has baseband DSP capability that I can migrate to any rig, any time. Is it as good as the IF DSP built in to the Yaesu FT DX-3000? Probably not. But it is a very, very good addition to an older radio, and its price, which once seemed high to me, now appears reasonable – especially compared to the expense of buying a newer HF rig.

Note that there is a version of the CLRdsp that is built in to a speaker. After trying this “DSP speaker” out, I opted for the CLRdsp box and added my own speaker, because the DSP speaker version lacked the tone control of the stand alone box, which I later discovered to work well with my rig, and it gave me more speaker options. This was the right call for me. Others prefer the DSP speaker version as more convenient for mobile use – it’s a personal call.
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