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Reviews For: MFJ-616 Speech Enhancer

Category: Audio Accessories for Transmitter & Receiver

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Review Summary For : MFJ-616 Speech Enhancer
Reviews: 23MSRP: 170.
Tailors the sound of your radio to your ears.
Product is in production
More Info:
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
K4RGN Rating: 2020-11-23
it helps, but... Time Owned: 3 to 6 months.
I have bilateral hearing loss above 1500 Hz. This product is useful and it also provides some operational convenience. However, a new unit is priced at more than $200. I wonder if the same improvement could be obtained from an audio equalizer at half the price. If you can get a used 616, go for it. I haven't noticed any quality problems, but the design and manufacture is thrifty to be polite. A few LEDs indicating the state of the pushbuttons would be helpful. I have not noticed RFI problems, but ferrites on audio cables is SOP in my shack.
N5USD Rating: 2019-08-02
Great for old ears Time Owned: 0 to 3 months.
Like many here, age and heredity have taken their toll on hearing and was wreaking havoc with my return to amateur radio. The MFJ-616 was virtually a last ditch effort to be able to understand the voice in the noise and the over driven voices on the quiet days. It has worked beyond my expectations. Is it perfect? No, but it now lets me be involved in QSOs that were not possible two days ago. I bought it used for about a third of the current price which makes it all that much better but it is worth the cost of a new one to me. It has taken SSB voices that were just a hash of sound and turned them into real words.
N7AG Rating: 2019-06-28
Overpriced! Time Owned: 0 to 3 months.
Same could be done with a low pass filter, least for cw. Or wear your hearing aids. Not impressed, may help some ops.
WB8RJY Rating: 2018-10-26
mfj-616 Time Owned: 0 to 3 months.
I , just like everyone else was skeptical, but was desperate to copy voice like i did when i was a 20 year old ham now that I am 65 .I bought a used one and was shocked as now i could hear ssb audio just like i was 20 years old again !This should be product of the year.I dont know any of my friends of the same age that dont have to ask their wife to repeat what they just said , often.rather you use an external speaker of a set of phones you will be shocked what this thing can do , it will change your life.tip, i had bd rf feedback with it when i would tx , powering it from the stations astron supply, using a 12 vdc wall wort completely cured the problem.
W9MT Rating: 2017-03-20
When it fully works, it does what it claims... Time Owned: more than 12 months.
I just bought my 2nd one at the Scottsdale AZ hamfest on 3/18/2017. Here's why...

I bought my first one at the Show Low AZ hamfest in 2013 from the sponsoring club's (Kachina group's) consignment table. It was purchased at a great price ($20), but when I got it home, the Volume Control was so poppy and scratchy that no amount of contact cleaner would save it. So, surgery was required.

Once equipped with a replacement Volume pot, I became very attached to this device. Even using a pair of original ClearSpeech DSP speakers with my MFJ-616, the audio boost/cut controls at 300Hz, 600Hz, 1200Hz, and 2400Hz really allow boosting intelligibility of voices. I was pleasantly shocked at how much mud could be reduced on a received SSB voice and make my FT-817 sound like a radio costing $1000's more.

So, I always was on the lookout for another one for a 2nd transceiver's use.

I saw my 2nd unit at last Saturday's hamfest and asked the price (with MFJ-1315 wall wart). The answer came back $20 again. I didn't even try to chisel the price down and happily paid the seller. I was told it worked and belonged to an older ham who recently became an SK who had used it a lot.

I brought it home and tried it out. It worked well in all respects other than the 300Hz cut/boost control did nothing. You could turn it all day...still no effect. The other ranges worked like they should. Knowing MFJ's quality problems and seeing some questionable solder on the pcb, I touched things up. Still nothing. A simple Harbor Freight "free pocket DVM" buzz out test pointed to (you guessed it...) another bad pot !!! I changed it out and now Unit #2 works like a champ. I plan to use this '616 on another radio.

Moral of the story is twofold...

The MFJ-616 is surprisingly effective when fully functional...and MFJ uses lousy potentiometers.

This one had a defective wiper. My old unit had one with a bad carbon track. I doubt the SK ever had the thing working correctly. The 300Hz pot was probably bad from the factory.
M0KFO Rating: 2016-04-29
Works well Time Owned: 0 to 3 months.
I managed to pick one up mint for £50, which was only a few weeks old. I reckon the seller just couldn't get rid of the ground/audio loop and wanted shot of it.
My hearing is fine, but it works great as an amp/equaliser to power a couple of speakers.

I don't use it as recommended, I just turn the frequency controls until it sounds best.

I did have problems with ground/audio loop to begin with. I have a doublet which shouldn't give any RFI. I tried it on the vertical which is 180ft away from the shack still had it, dummy load still had it.

So, then went looking at what else it could be, I have snap on ferrites here and there. I made a shielded lead from RG58, no luck. I put an isolation 1:1 600 ohm transformer, no luck. What cured it eventually for me, was three ferrite snap ons on the two PSUs (recommended not to run the 616 from the same PSU as the rig) and three on the power cable at the rig end. And some on the speaker leads.

Now I just acquired a Ten Tec 715, seems the same problem, so looks like doing the same again, to sort that.

W1EQO Rating: 2016-03-03
This box works Time Owned: 0 to 3 months.
If you are a contester, try one. Esp for the low, noise, bands.

I bought the box because I thought I had a hearing issue; over the years busted calls were creeping upward. So I bought a 616 box as a partial solution.

What happened was that I could pull the weak European calls out of the mud. Yea!

Jim, W1EQO
K4EJQ Rating: 2016-01-14
"Second" N4GW's Note Time Owned: 0 to 3 months.
AD5HD Rating: 2015-07-28
Too much hiss Time Owned: more than 12 months.
This is a four channel parametric EQ covering 300Hz to 2400Hz. To obtain improved intelligibility the lower frequencies must be cut and the higher frequencies boosted. But if the audio chain generates a lot of hiss then the cut/boost simply makes it worse. Using it following a DSP denoiser (Timewave DSP-599zx) which is very quiet this hiss then obviates some of the benefit of the denoiser function. It's pretty annoying and makes it difficult to find a compromise setting that minimizes noise while maximizing intelligibility especially with weak signals. The noise arises entirely from the TL084 used in the EQ section. It's a perfectly acceptable audio opamp but not exactly low noise. Likely possible to improve upon it by changing out to a better quality opamp so that's next on the list.
KB0RDL Rating: 2015-06-20
Bad luck with mine. Time Owned: 0 to 3 months.
After reading the great reviews on EHAM I decided to buy one of these to clear up the bassy "muddiness" I was listening to on 80 meters. The difference is that I bought the MFJ-618 which is identical in function but is designed to adjust two speakers individually instead of just one. I ordered from it DX Engineering for $219.95.

When it came I noticed that the unit was damaged although the box it was packed in at the factory was not, which meant that it happened at the factory. It had apparently been dropped on a concrete floor and bent a corner in but they packaged it anyway. Reasoning that it may have damaged the circuit board I called DX and they immediately replaced it for me. It was great service and they paid shipping both ways.

I hooked up the second unit and was surprised to notice that the sound adjustments produced no noticeable change in either channel. A few days later I was sitting my shack with the unit on and it started putting out some terrible audio hash all on its own. The radio was off at the time.

I tried to troubleshoot the unit. I tried different power supplies, different speakers and a different radio. Nothing worked. It was apparently a defect in the unit. I called DX and they are sending me a Mountain West noise reduction unit as a substitute plus a refund for the difference in price. I ran through my troubleshooting procedure with the technician and he agreed that it was the unit.

I feel awkward about this because everyone else has reported such good results and it's likely that I just got a bad unit, which can happen with anyone. The thing to remember is to buy it from some place where you have recourse if it doesn't work. DX Engineering was great.