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Reviews Categories | Filters, Audio: (DSP and others) | ClearSpeech base unit Help

Reviews Summary for ClearSpeech base unit
ClearSpeech base unit Reviews: 33 Average rating: 4.7/5 MSRP: $179.95
Description: Stand alone audio DSP unit
Product is in production.
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W4KVW Rating: 5/5 Aug 24, 2016 20:04 Send this review to a friend
Still Amazing! {:>)  Time owned: more than 12 months
I wrote my last review in October 2013 & just wanted too say that the ClearSpeech Module is still taking away unwanted noise even Today & I have upgraded from the ICOM 756 PRO II to an ICOM 7600.It even makes the receive on that wonderful rig even better as it does on any receiver.I also use one on every all mode rig that I operate on any band because it makes listening so much more pleasing when it removes static & white noise.Makes most any radio sound like the antenna is not connected because it kills the noise on SSB,AM,& FM.I could operate without one but I choose not to do so & I won't.Get you one & you will love it as well. Still a shame they stopped building the base model because it can be used with any speaker & that's a big plus. {:>)
N5XJT Rating: 4/5 Jan 19, 2015 08:40 Send this review to a friend
Good Unit!  Time owned: more than 12 months
Works very well with older non-DSP hybrid rigs and will accomplish about 70% noise reductions. Also works well with my newer FT-840. However, be sure and use a good 12v DC supply or you will get a noticeable hum. The "waterfall" noise effect is often present although this seems to moderate after about a 1/2 hour of warm up and is a very minor distraction. Overall a nice improvement allowing the user to hear many qso's that otherwise would be lost. Definitely worth the price (around $100 or so used) and I recommend it.
NW8Z Rating: 5/5 Oct 10, 2013 12:41 Send this review to a friend
Excellent at Beating up QRM or QRN  Time owned: 0 to 3 months
I picked up this gem on Ebay for $125.00. It's a little higher priced than most have been selling for, but for what it does it's worth every penny and then some. You'll be listening on say 40 Meters, and there's a lot of hiss and static crashes. You just turn on the ClearSpeech base and the hash and static is either gone or severely diminished. It works and you see very few of these filters out there as they just plain work, period! No more tuner uppers either as it gets rid of the noise on the band of someone tuning up. I took a chance getting one of these but the reviews speak for themselves. I got a version one base unit. Version II put in an LED to indicate when the filter was inline and also allows you to not have to have the unit on to pass the audio. I put in a RED led to indicate 12Volts of power and another BLUE led to indicate when the filter is one and inline and when it is off.

Get one of these if you can find it, it's worth it's weight in GOLD and works.



NL7FK Rating: 5/5 Oct 23, 2007 04:24 Send this review to a friend
Best thing one can add to their station  Time owned: more than 12 months
I have used the clear speech base unit for some time now and I truly love it. It is a shame they are so hard to find now a days. I guess those who have them hold on to them for life.

The filter bought new life to my Mark V's receiver. It is now a pleasure to work 40 and 80 meters. It is one of the very few filters that actually eliminates static crashes while not degrading the desired signal.

I feel this is a SSB filter. I found it hard to use on CW but it was possible. If you are a ssb operator and are tired of noisy conditions and are tired of fighting with static crashes this filter is for you. Grab one whenever you can. They are the best addition one can make to their shack.
VK5FDMR Rating: 5/5 Mar 14, 2007 03:32 Send this review to a friend
Nothing less than "Outstanding"  Time owned: more than 12 months
Hi everyone,

I have owned my Clear Speach Base unit now for many years, now it makes me wonder how I managed before. The way it eliminates QRN and QRM is amazing.

I use it in my mobile as well as at home on my base radio. My HF radio an Icom 751A is a great radio however I do get the usual noise floor levels that most non DSP type radios suffer when the bands are noisy. With the CSB unit in line the transformation is just amazing infact, nothing less than outstanding. I have also used my CSB in line with a new Icom 7400. The DSP offered in the 7400 is outstanding but when I added the CSB in line it really polished off what was already great rx audio.

There is nothing to say that you can not use the CSB in line when using VHF or UHF either. This I have tried and am pleased with the result esp if you are trying to work someone or a repeater that is way off in the background amongst the white noise. It cuts through white noise like a hot knife through butter. However having said that I don`t think you would need to nor want to use it in line if you are on your local repeater at 5-9+60dB. The rx audio would be quite watery.

This is truely an amazing product. I highly recomend the CSB and I wish I had another so that I could have one in my mobile and the other in the shack to save me moving it around.

Thanks for reading.

Best 73 de Dave VK5FDMR
K3MOV Rating: 5/5 Aug 21, 2005 16:24 Send this review to a friend
Don't use your rig without it!  Time owned: more than 12 months
I bought my base units when they first came out -about six years ago. I have used them with a TS 570 D, TS 2000, ICOM 775, ICOM 706 MkII, 756, 756 PRO, 756 PRO II and FT 1000. The performance of each of these rigs was greatly improved when the ClearSpeech was in line.

I recently disconnected the unit from my PRO II in order to use it portable with my TS 570 D. It worked its usual magic of wiping out white noise and tuner uppers while in portable use. When I returned home, I delayed hooking it up to the PRO II again because we were going on another trip, and I would have had to disconnect it again.

The difference in the quality of the received audio of the PRO II is like night and day without the unit in line. For example, when 75 DX occasionally opened during the past several weeks, I would usually throw in the towel early because I could not tolerate the static crashes. This type of QRN is routinely handled by the Base Unit when it is in line. Without the unit in line, I also have been hearing an endless variety of stray, strange noises which simply are not there when I flip the "on" switch.

Its plug and play design is another feature that I really enjoy. I tried a GAP "Hear It" In Line Module recently. Although it was more expensive than the ClearSpeech, it required much more tuning and the audio it produced was not nearly as clear.

I have seen a lot of reviews from operators who state that they have yet to hear any DSP filtering worthwhile. I suggest that they give one of these a try, if they can find one. Unfortunately, they are no longer made. Bob Heil has taken over the manufacture ClearSpeech and apparently is only making an "upgraded" speaker unit which is quite large. I'm glad I bought two of the originals when I had the chance.
KD3V Rating: 5/5 Aug 16, 2003 15:29 Send this review to a friend
new rig means another Clearspeech!  Time owned: more than 12 months
I just got my SECOND Clearspeech because I am totally spoiled by the performance I have had for 18 months using it with my IC-706. I got another one for my old IC-745 which just returned to my shack.

I define its performance as a "Q raiser". It raises the signals Quality level from Q2 to Q3, Q3 to Q4 and Q4 to Q5.

I find I leave the volume control higher while just listening to the rig in the background.

There is no longer any annoyance due to white noise. Some types of QRN can still get thru but for the vast majority it makes using the rig much more relaxed.

I will get one for each SSB rig that I ever have. Two units should suffice for quite a while now.

I bought the base units since I already had a preferred set of speakers and did not need more.

I velcro them to each rig and rarely turn them off. They have become a permanent part of each rig.

One very neat extra step I took for the use with the IC-706 was to integrat the DSP audio into the rig. When using the remote-head I wanted to be able to have the DSP processed audio come out of the front panel speaker jack (and also in case I used a headset from the mic jack).

After studying the schematic and internals I found a simple method to integrate the audio. If there is enough interest in this modification I will write the details.

N5HF Rating: 5/5 Jun 8, 2003 18:42 Send this review to a friend
Works Great  Time owned: 0 to 3 months
I've had mine for 2 weeks. It is a base unit but am using it with a 718 and external speaker in the mobile.

Bid on the unit during ebay auction. Did not win unit. Winning bidder did not come through so seller contacted me direct and I bought unit. Unit arrived with broken toggle switch--seller told me that it was in perfect condition (caveat emptor). Called Amcom and spoke with Carlos who was very helpful. Offered upgrade kit (new switch, current limiting resistor and led) for $18.95 appx with self install. Kit arrived but was for speaker filter model. Again spoke with Carlos who told me to send the unit back and he would do the upgrade at no additional charge. Did this. Unit came back one month later. Something rattled inside when I shook it. Opened unit up and found an orphaned 4-40 (I think)screw loose inside the case. Visual inspection showed everything ok. Removed screw. One of the panel screws was also stripped but this may have been done by the original owner. Connected power and the filter works fine.

The filter performs as advertised and it is great.
It makes for a much more liveable environment in the car and my wife does not complain as much.

I too notice the "whisper effect" and the delay time at the end of a transmission.

I am not an EE and the supplied documentation is kind of weak but this is what I think is happening.

The filter dgitizes the incoming waveform and does an FFT on the result. A convolution operator is designed on the fly using the results of the FFT. The operator is designed so that the periodic "noise" components of the original signal are not included. This operator is then convolved with the original incoming signal and the result is sent to the speaker. The things that can be accomplished with a dedicated microprocessor are truly amazing.

It would be instructive to compare the audio before and after filter insertion to see exactly how much of a delay is introduced by filter insertion.

The "whisper effect" is probably an artifact created by short operator can be eliminated but you would need lots more microprocessor power to do it. The delay time is due to the dsp resampling the incoming signal in order to update the operator.

I have also noticed that sometimes the filter just seems to "stop working" (ie the noise comes up for no reason). I attribute this to the noise component of the original signal changing. When this happens, I just turn the filter off and restart it so that the convolution operator is redesigned around a sample taken from the current input.

The filter works great.

The only downside to all of this is that I use the filter with the mobile rig. I probably have an S2-3 noise floor. It used to be that if I could hear a signal, I stood a reasonable chance of working the station. Now I hear lots of stations that are extremely weak. I cant compete with the wide-spaced yagi crowd in working these people.

Sic transit gloria.

Would definitely recommend the purchase.

N1WL Rating: 5/5 May 24, 2003 17:54 Send this review to a friend
Excellent Addition to your rig  Time owned: 0 to 3 months
I have an Icom 756 that has a high noise floor. I tried out a friend's Clear Speech Base unit and the the Clear Speech knocked out the white background noise substantially. It also took out the tuner uppers, and static crashes. It Made listening to the Icom MUCH more pleasurable.
I ordered one for myself the next day. I also lent it to fellow Ham to use on his rig, the next day I asked him how he liked it, He said he ordered one as well..What can I does what is says it does!
KW4CQ Rating: 5/5 May 6, 2003 22:03 Send this review to a friend
Kills the storm static nicely!  Time owned: 0 to 3 months
Hooked up the filter between my Kenwood TS-870S and the Gekko 14 inch flat wall mount speaker being sold at a discount by Am-Com. I use this speaker in combination with a Yamaha 6 inch powered sub-woofer to tailor received SSB audio for a nice room filling lifelike sound. The reduction of storm static and QRM generated noice is quite remarkable and results in clean relaxing audio from the speaker. Perform much better than the Noise Blanker in my TS-870S.

Two relatively minor design recommendations however:

1. The filter should be provided with a front panel mounted eadphone jack in addition to the existing rear mounted mini jack. The ability to switch filtered audio between headphones and speaker would be a great addition too.

2. I would prefer to see the filter available with either a built-in power supply or a power pack offered as an option.

I give it a 5 rating.

Bob, KW4CQ
Reston, Virginia

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