UR6QW Audio Processor

Please read about how you can help UR6QW in Ukraine here

Edit: the setup which I use now is detailed in this post. Read on for the review…
Also: UR6QW EQ Version 7 is out – a full review coming soon!

I recently bought version 5 of the 8-band EQ from UR6QW in Ukraine. This is a high quality audio processor for your ham radio. I chose to purchase the IC-7300 version for my SSB voice comms. The device has an 8-band graphic equalizer, a low noise microphone preamplifier, an audio compressor, noise gate with variable level and attack/release time, and an echo processor (for those who might want to connect it to a CB radio 😉 !).

According to UR6QW, the device works with both electret/condenser type microphones and dynamic microphones. However, I did measure +5V electret bias voltage on pin 1 of the 8-pin microphone connector (which makes sense since this bias voltage is required to drive the stock ICOM HM-291 electret microphone) and I also measured the same voltage on the tip of the 3.5 mm external microphone jack.

Anyway, I want to use this socket for connecting a dynamic microphone so I installed a DC blocking capacitor in series with the tip connection of the 3.5 mm socket so that there is no DC bias supplied to the dynamic mic. Of course, this 3.5 mm socket will no longer drive electret microphones, but it gives me options. This 5V bias voltage is supplied through a high resistance (several kohms), so it’s incapable of sourcing much current, but I didn’t want it on the dynamic microphone coil at all, so, capacitor it was! I chose a 10 µF, 16 V electrolytic capacitor, connecting the positive side towards the bias voltage. There is no need to use non-polarized capacitors in this application. More information about adding a DC blocking capacitor here.

The device I bought is powered via the IC-7300 microphone connector, and requires no external power supply. It has an external 1/4 inch PTT switch jack on the rear, and a couple of 1/8th inch jacks for a headset (headphone/mic) on the front, as well as a connector for the Icom microphone. Up/Down buttons on the microphone still work when using this processor. For those interested, here is a link direct to UR6QW’s page.

In the past, I’ve given ESSB quite a hard time, and I’ve said that listening to people who use noise gates is tiring on the ears. It seems unnatural. So, here I am with my very own processor capable of producing ESSB with a noise gate. Is this a case of “if you can’t beat them, join them”? Maybe.  ESSB is somewhat difficult to achieve on the IC-7300 since its maximum transmit bandwidth is 2.8 kHz (filter range from 100-2900 Hz) so the deep lows and crisp highs are cut out of the audio whether you like it or not, via the radios internal software. However, it is important to remember that filters don’t just cut off with infinite dB of attenuation. I don’t know the filter profile of the transmit bandwidth filter, but adding 6-10 dB of boost outside of the limits of the transmit bandwidth filter should still yield some boost after the filter.

The UR6QW device is very easy to set up using the monitor function on your radio, but I chose to set it up initially while listening to myself on another radio. I further tweaked the settings over the air with the help of W5IFN and AG5DB.

For the stock HM-219 mic, the settings I eventually settled on for my IC-7300 and processor were as follows. Your optimal settings may be different.

When using Behringer XM8500 microphone, the settings I initially settled on for my IC-7300 and processor were as follows.

Then – after a weekend of contesting, using Behringer XM8500 microphone, the settings I finally settled on for my IC-7300 and processor were as follows. I ended up using the compressor in the IC-7300 rather than the compressor in the UR6QW device, since it seemed to provide a much better average SSB power level.

The following are the settings which I settled on, and had used for almost six months. They were pretty good ragchew settings, but I ended up compromising between these settings and a more DX-friendly setting. See those settings here.

Overall I am very happy with my purchase. I received great audio reports over 9000 miles DX. This device packs a punch in your audio. The processor is of a very high quality. Shielding is good, shielded cables are used, and the housing is metal. The legend is silk-screened onto the housing in thick white paint. The knobs are of high quality and the potentiometers feel solid.

This processor is extremely competitively priced considering its high quality build, connector options, and its audio functionality and quality.

So far, I give this 10 out of 10!