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Reviews For: bhi ParaPro EQ20-DSP

Category: Filters, Audio: (DSP and others)

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Review Summary For : bhi ParaPro EQ20-DSP
Reviews: 6MSRP: $379.99
Description:
The bhi ParaPro EQ20 features a 20W modular audio power
amplifier with a parametric equalizer, plus the latest
bhi dual channel DSP noise cancelling technology. The
parametic equalizer allows any specific part of the
frequency range to be selected and adjusted in strength
to suit your conditions You can adjust the controls to
determine exactly how the equalization is applied,
allowing you to select which frequency to adjust. The bhi
DSP noise cancelling provides mono and stereo DSP noise
cancellation to improve the speech quality in all types
of radio and voice communications.
Product is in production
More Info: http://www.bhi-ltd.com/
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0064
K7FD Rating: 2022-05-26
Works as advertised Time Owned: 0 to 3 months.
Purchased for use with several older receivers; Palstar R30C, Icom IC-R70, and Drake R7. As with most DSP noise reduction I’ve used, the stronger the signal the better it works. Weak signals near the noise floor not so much. That said, the BHI does a better job than other external DSP NR boxes I’ve played with. IMHO, combining the parametric EQ with the DSP noise reduction makes this unit stand above the competition.

I’ve used the BHI on CW, SSB, and AM modes with very good results, taking care to adjust the input signal as instructed in the manual. This is critical for best noise reduction. Digital artifacts are minimal but still audible to the discerning ear.

All in all, another handy tool in the fight against high noise floors and listener fatigue.

John K7FD
HZ1ES Rating: 2021-09-14
DSP ok, but unit needs improvement Time Owned: 0 to 3 months.
After thinking about 12 months, I ordered the ParaPro EQ20-DSP, main reason being that I couldn't stand the continuous AGC triggering by the noise anymore.
I am not an audio engineer like the previous reviewer, but I am an audiophile and sound quality matters to me a lot even for 2.4Khz limited audio on HF SSB.
The DSP function of the unit definitely made the unbearable background noise (SSB/HF) disappear. The audio after the processing is not exactly the same as the original, as if the total audio bandwidth is narrower and squeezed. In my case DSP works better if the DSP of the radio is switched OFF. DSP is working in a different way than TRX DSP's. TRX DSP always keeps the manually adjusted level. This DSP acts like an automatic Squelch at the adjusted level. In the beginning the noise is heard extremely loud; the transition time is not 500ms as stated in the user manual, it is most of the time around 900ms until DSP starts to work. More annoying is that this is being repeated every time you switch from TX to RX. This is similar to an FM device where the Squelch is open after every transmission1.5 seconds long. I think this time should be reduced in the next generation or a better way, DSP should keep the last settings without starting from scratch analysing the incoming audio. During a quick move along the band between signals DSP is always working, the same can be applied for a fixed duration of 2 seconds after every mute. It is not comfortable to hear the very loud noise before DSP takes action. A work around to reduce the high level noise is using the NR of the transceiver at a low level.

The noise is actually not cancelled, it is being transformed into a different form and the level is reduced heavily. It can still be heard in the background which sounds like water floating in a river or like a slow shower. One way of reducing this water effect is to use TRX NR at a lower level and BHI DSP together. The user has to prefer one or other. To my opinion BHI DSP needs noise to work properly, reducing the noise first with the TRX DSP reduces audio quality little bit together but reduces the water effect, as well.
However there are many points requiring attention in detail, which I think was not the case in the first design, but can be considered in V2.0? :)
Points IMO requiring improvement:
- There is NO BYPASS ! As the unit is between the radio and external speaker, common sense would have meant that once DSP is switched off, audio is bypassed to the speaker.
- Once the unit is switched off and on again the selected input returns to stereo. I use channel 1 mono. Was it so difficult to remember the last position?
- There are LED's showing selected input. They are bright like a flashlight directed to your eyes. I had to put some stickers on them to dim. The LED on LDG tuner is 1 Lux, on BHI 23 Lux.
- The DSP function once switched on starts hard and quick; on higher levels when you turn the potentiometer its is very smooth, but not in the beginning.
- Many Transceivers have an audio output where an external speaker is connected and the volume control is on the Transceiver. I assume all hams are very much used to this. With DSP in between you should train yourself to adjust the volume from DSP unit! At least for me this is very annoying to use the bad quality volume control knobs instead of the luxury perfect TRX volume controls. DSP is very sensitive about the input level, once a threshold is reached the LED starts blinking making the regular use of the TRX volume controls impossible. A good design (V2.0) would be that the DSP functions as an amplifier without any volume control, where the TRX is acting as a pre-amplifier and operator can continue using the TRX volume controls.

Summary: DSP function is ok with some acceptable audio quality loss. Operation of the unit requires lots of improvement.

BONUS Feature:
Almost forgot to mention. If you live near a powerful AM transmitter (mine is 30km away) and you connect two audio input cables to each of the channels you can start listening to AM broadcast radio!!

73's
Emre
HZ1ES
W6UXB Rating: 2020-09-15
Good but not great Time Owned: more than 12 months.
UDATE:

I have just read the VA2DV review of this unit and I would like to add my observations, Class D amplifiers need a very good load on them and not be over driven, they also do not like switching power supplies I use an linear Astron for mine and drive it to a pair of 3 1/2 speakers from Parts Express, but as the old saying goes garbage in garbage out so feeding this with an RG ONE which has the best sounding audio of any HF radio I have heard I am now feeding it with brilliant in and brilliant out! After an hour or so I do not feel any listening fatigue. The DSP is OK

After reading W5ZYX revue I have decided to add my review of this device, I would like to pre-face that I have been a professional live audio engineer for 35 plus years. As far as the DSP goes it works pretty good like any audio DSP the further you add noise reduction the further the audio gets garbled, this is pretty good on settings 1, 2 or 3/4 but further on the sound is 'under water' The EQ s OK but for a parametric EQ 3 bands would be a lot better plus + or - 12-15 db would be better than the + or - 10 db that this unit has, also I would like the input select to remember the last setting, finally this is a class D amplifier you have to remember to keep the speaker outputs isolate you can't connect both speaker - leads together. I do like the 2 inputs and switching as I have described on my QRZ page
VA2DV Rating: 2020-09-13
Way overpriced. Time Owned: 0 to 3 months.
I got one out of curiosity to pimp up an FT-818 I was using at home. While the DSP noise reduction works great, the low audio quality (class-D) output makes it hard to listen for long periods. The case is made of cheap plastic and the overall quality is not even near the level of the asking price. I was able to sell it on Ebay at a great loss and even then, I was feeling ashamed.
VK3BDX Rating: 2020-08-14
Works well at reducing Noise Time Owned: 6 to 12 months.
Live most of us in the suburbs noise is an issue. My noise is compounded with two sets of Power Lines through the property. I picked up the BHI ParaPro at Dayton in 2019 and took it back it VK.

I was impressed with its noise reducing ability, but not overwhelmed. A few months later it developed a couple of issues, so I returned it to the UK and Graham had no hesitation in replacing the unit for me. Great Service.

WOW what a difference the performance of the units was like chalk and cheese I am honestly delighted with the noise reduction capabilities. It is impressive.

Graham also sent me the new ATT2 Attenuator Pad. This allows you to increase the volume on the radio without overloading, the circuits in the EQ20. This works extremely well and allows a much wider range of the volume control to be used.

A great product backed up by great service.
W5ZYX Rating: 2019-05-11
So good it blew me away! Time Owned: 0 to 3 months.
It might seem like I'm expressing Christmas Morning enthusiasm about a new toy but I received a bhi ParaPro EQ20-DSP earlier this week and its response to band noise on 75 meters was nothing short of amazing. Last night in Southeast Texas there was tremendous lightning noise and tonight (my second night to own the EQ20-DSP) band noise is running a steady S7. How good is the EQ20 at quieting the noise down? It takes darn near all of it out of the audio stream. I've owned several digital signal processing units over the many years I've been licensed and this thing is world class amazing. Its performance simply blows me away! On SSB, while the station I'm listening to is transmitting, there is ZERO band noise in the audio. The only time you hear noise, and very very little of it, is for about a half-second after the transmitting station quits talking.