Kenwood TS990

Welcome to our Kenwood TS990 Resources and ESSB audio page

After many years of running the Kenwood TS870 – it was time for an shack upgrade.
The 870 has been a superb workhorse and coupled with the W2IHY 8-Band EQ, W2IHY EQ-Plus and Heil Goldline GM5 (now discontinued) this line-up has served me extremely well for over 15 years. The TS870 is known for its great audio and coupled with the W2IHY gear it really did sound pretty good.

UPDATE for March 2020. The shack renovation has been completed with the help from my XYL Gail who’s a great decorator. She also helped choose the colour scheme. The shack is having the last parts done with respect the wiring then all will be good. All being well, I should be back on the air in the Summer of 2020. All that’s needed now is the final work on the new antennas which are all built and tested – and motorising of the two tower winches. As a finale, I’ll also put the 40m 4-square into service using a Comtek ACB-40 phasing box.

Kenwood TS990 Transceiver

So what’s going to be new here in the Vortex shack

Kenwood TS990

That’s the first addition. Here’s a run-down from Kenwood UK and a PDF download of the RADCOM review from June 2013 by Peter Hart G3SJX. In addition – here’s the February 2014 ARRL QST Review by Rick Lindquist WW1ME PDF Download.

Avalon VT737SP Audio Processor – Main Processor

The ‘Avalon VT737SP Audio Processor‘ is probably the world’s best know professional tube pre-amp and compressor. Used by artists such as ‘Michael Jackson’, ‘The Spice Girls’ and ‘Shakira’ just to name a few, this baby really rocks. The VT-737 has three input connectors: a front panel unbalanced quarter-inch mono TRS jack and rear mounted XLRs for the transformer balanced microphone input, and discrete high-level class-A Line input amplifiers. Alongside the pre-amplifier is the opto-compressor which features twin class-A triodes for gain matching. The amount of control for the dynamics is enough to put most compression boxes to shame.The four-band EQ isn’t parametric, nor is it the standard sweep variety, it’s more of a cross between the two. The two mid-range EQs are probably the most dynamic equalizers you will find on any pre-amplifier. Many equalizers will sound good when they are processing signals, but fail the test when they are set to flat by colouring the signal that passes through them. Not so with the VT-737. All-in-all you’d struggle to better it. See more here on Avalon’s site, read some reviews here and see what the pro’s think here.

Coming soon – Avalon VT-737SP Audio Processor
Tube upgrade to E188CC tubes

A great audio upgrade for the VT-737SP by using premium E188CC (NOS – ‘New Old Stock’) tubes in place of the standard Sovtek 6922’s. Not the cheapest option – but wow, can you tell the difference.

Symetrix 528E Audio Processor – Secondary Backup Processor

The ‘Symetrix 528E Audio Processor‘ is not new but over the years has developed a following in the ham community as being one of the best audio mike pre-amps and compressors around. Originally manufactured in the early 1990’s by Symetrix of Washington State (USA), the 528E became extremely popular in the early days of ESSB. Although now discontinued, it is still in high demand. Probably only bettered by the superb ‘Avalon VT-737SP‘ Mic tube Pre-amp.

Klark Teknik DN-370 Professional Analogue EQ

Designed and manufactured in the UK, the Klark Teknik DN370 is a modern 30 band dual-channel EQ which is a current 2018 production model. Klark Teknik designs and develop professional signal processing and audio equipment. Located in Kidderminster, Worcestershire, UK, the company was founded in 1974 by brothers Terence and Phillip Clarke. It developed a number of new types of equipment in the audio field, winning a Queen’s Awards for Enterprise in 1986 so we are proud to run some ‘British’ hi-end audio processing gear here at Vortex.

Reviews of the DN370 say this is a superbly clean unit being extremely transparent.
The Kenwood TS990 has an in-built 18-band EQ and whilst this covers the central part of most audio frequencies, it cannot handle frequencies below 100hz and above 5.1khz. Given that the microphone response of the TLM103 is in the range of
20hz-20khz, the DN340 will enhance areas where the generic 990’s EQ can’t reach.

To quote from a current owner..
“This professional hi-end EQ is a real beauty. Great controls with 45mm oil-damped sliders and fully balanced inputs and outputs it just oozes quality. It’s certainly not one of your run-of-the-mill graphic EQ’s.

First live test last night and it had the best musical sound. It’s very, very clean and superbly transparent. Variable Notch filters are VERY powerful tools, >18dB attenuation, Q=32. A couple of well located notch filters, one at 90Hz augmented by further attenuation on the relevant fader gave me -30dB (at very high Q) there for some nasty in-room resonances, and -18dB at 250Hz (notch filter alone) cleared up some endemic muddiness. The Proportional-Q (versus prior Symmetrical-Q model) seems to have reduced / eliminated “ripple” effects. The result is remarkably increased clarity and a unit that just shines above everything else.”

Neumann TLM 103 Microphone

The Neumann TLM 103 is a large diaphragm condenser mic used in many professional recoding studios. Often regarded as a studio ‘Workhorse’ and manufactured by Georg Neumann (Berlin), Germany. The Neumann name is one of the most famous in the broadcast industry and mics such as the famous Neumann U87 need no introduction. Our own Neumann is the TLM103MT Studio Set. The ‘MT’ suffix refers to the microphone finished in black rather than silver/nickle.

Quote from a professional user

“The TLM 103 is nothing short of amazing and for the price, such an affordable way to get into the pro league. Once you have had the Neumann experience you will understand why these microphones are such an industry standard and sought after by many. From the moment that you open the elegant wooden Neumann box to the moment you put the TLM 103 to bed after a session, you’ll notice that you have been smiling from ear to ear!”

Link here for a selection of user and owner comments on the TLM103

Kenwood TS990 Resources and Files


  • User Manual – Download Here (63Mb)
  • User Manual (INCLUDES NEW 2019 V1.23 FIRMWARE UPDATES) – Download Here (93Mb)
  • Service Manual Part 1 – Download Here (8Mb)
  • Service Manual Part 2 – Download Here (10Mb)
  • In Depth Manual – Download Here (16mb)
  • Amplifier Keying – Wiring Data – Download Here (0.1Mb)
  • Kenwood Network Command System (KNS) Revision 3 – Download Here (1Mb)
  • Kenwood USB Audio Manual – Download Here (0.4Mb)
  • Kenwood PC Control Command Manual (V2.0) – Download Here (0.8Mb)
  • Virtual Comm Port Driver Setup – Download Here (0.8Mb)
  • TS 990 Brochure PDF – Download Here (2Mb)
  • Kenwood Software Links and Documentation

  • Current TS990 Software Direct from Kenwood – Link Here to Kenwood’s Site
  • TS990 – ARCP 990 V1.04 Download Here (36Mb)
  • TS990 – ARCP 990 V1.04 – Info PDF Download Here (0.2Mb)
  • TS990 – ARUA 10 V4.00 Download Here (6Mb)
  • TS990 – ARUA 10 V4.00 – Info PDF Download Here (0.2Mb)
  • TS990 – Virtual Comm Port Drivers (Win10) Download Here (1Mb)
  • TS990 – Virtual Comm Port Drivers (Win7/8) Download Here (6Mb)
  • Mods

  • MARS Mod and Expanded TX (Tnx PA2DB) – Download Here (0.1Mb)
  • Add an IF Output port to your TS990 (quite involved) – Download Here (3.3Mb)
  • Retransmit Recorded Receive Audio (Tnx WD8DAS) – Download Here (0.1Mb)
  • Transmit Output Power (Tnx WB4JWM) – Download Here (0.1Mb)
  • Noise Blanker 2 (NB2) revised functionality – Download Here (0.1Mb)
  • Current Firmware

  • PDF list of all firmware revisions (Up to V1.25 March 2020) – Download Here (4Mb)
  • The latest firmware (V1.25) March 2020 – Download Here (13Mb)
  • Firmware Tip!! – Your USB/Memory Stick should be formatted ‘FAT32’ for the TS990 to read it successfully – ‘DO NOT FORMAT NTFS’ (The TS990 does not have an NTFS file system!). When you have formatted your USB stick, place the firmware ‘zip’ file in the top-level route directory.
  • Old Firmware Versions

  • V1.24 – Download Here (13Mb)
  • V1.23 – Download Here (13Mb)
  • V1.22 – Download Here (13Mb)
  • V1.21 – Download Here (13Mb)
  • V1.20 – Download Here (13Mb)
  • V1.13 – Download Here (13Mb)
  • V1.12 – Download Here (13Mb)
  • V1.06 – Download Here (13Mb)
  • Other Resources

  • Add a second SP 990 Speaker to your line-up (Tnx ZP5BVK) – Download Here (0.1Mb)
  • Upgrade the speaker driver unit in the SP 990 – Link Here to Phonema Speakers
  • SPRING 2020: (Sorry – ran out of time for Winter 2019) SP990 Speaker enclosure modification with internals by QTA Systems, Cambridge – UK. I did some initial ‘Rough’ mods but want to put a nice document with all good quality images on here. Given the time, this project is now for early 2020.
  • TX Audio Setup by AB4BJ – Download Here (0.2Mb)
  • Join the Kenwood TS990 .io user group here – a multitude of 990 owners and real-time user information.
  • More links and resources will be added when available

    Do you have a TS990 related item to share? – if so send it to us for inclusion on this page

    This page and links last updated March 12th 2020