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Outboard 12v audio amplifer recommendations?

I live off-grid, all solar power. Have been using vintage Polk Audio monitor speakers for a clear natural receive sound plugged into the back of the K3. Am preparing for the 6500 to arrive and reluctantly bought a pair of Bose Companion Series iii amplified speakers because for some reason unknown to me the Flex has no onboard audio out amplifier. Tried these Bose speakers and honestly, they sound terrible. They have no highs, are way too bassy natured and marginal clarity that in no way am i going to spend hours listening to. There are better amplified speakers out there, but most do not operate off of 12vdc. Decided to spring for an outboard amp to drive my existing speakers. I know there has to be a decent 12v stereo amp out there that has a metal case that can be grounded to act like a faraday cage and keep RFI to a minimum, and that can run seamlessly to where you only need to adjust the radio volume to control speaker volume, without needing to touch the amp. Any suggestion by you audiophiles in the forums? Is this a practical solution in your opinions? Thanks..


  • WA2SQQ
    WA2SQQ Member ✭✭
    edited January 2017
    Look to the large variety of PC speakers.
  • K7NXT
    K7NXT Member
    edited December 2015
    Agreed, and the "bluetooth" connected speakers for iphones are amplified. Many have a wired input option. I use a Bose Soundlink 3 with my Flex 6500.  Bill, K7NXT
  • Walt
    Walt Member ✭✭
    edited July 2017
    I have two Pyle 12 vdc amps working at this shack - they sound great and are low priced.  Use Amazon to search for Pyle amps.  You will find several under $50.  Then you can pick your own speakers.  I bought a few from amazon also - sit behind the monitor and do well.  Everything runs 24/7 and have for the last 4 years (Flex only running for 18 months . . )


  • EA4GLI
    EA4GLI Member ✭✭✭
    edited November 2016
    No RF issues?
  • Walt
    Walt Member ✭✭
    edited December 2016
    No RF issues - no RF suppression - but I need to explain, I only run 100 watts and my remote LDG RT-100 antenna tuner and little antenna wire is located out in the yard, with an RF choke and buried feedline coming into the shack. 

    So no big 2KW amp or antenna tuner going to high-SWR coax within 3 ft. of the audio amp. which may occur in other stations.

    Hope that helps.  Also use a Lepai TA2020 that I bought from amazon for $25.

    Good luck !

  • Phil - N6ERP
    Phil - N6ERP Member
    edited October 2016
    Very Interesting !!-Thank You.. That's exactly what I was searching for.. Awesome..
  • Mark_WS7M
    Mark_WS7M Member ✭✭✭
    edited December 2015
    Phil, I commend you for being off grid.  That is amazing.  I wish I could get off grid.  My power company is **** the life out of us.

    My ex-boss who is a multimillionaire removed his house in CA about 5 years ago and got in on the solar panel trend.  Basically state of CA paid for his solar system (almost, he is shrewd business man) and now days his electricity runs him about $200 per year.  Most of the time he's getting paid by the power company rather than paying them like I do.

    Sigh... I would love to get there!
  • EA4GLI
    EA4GLI Member ✭✭✭
    edited November 2016
    Ah ok. I have tried several pieces of audio close to the radio and it is very difficult not to have some rf bleed into the equipment. It makes sense in your installation as it is very well built to avoid RF. In mine, even the length of the rca cables connecting to the bose speakers can have an effect on getting some rf in the shack.
  • Mike
    Mike Member
    edited December 2015
    Check this out. http://us.banggood.com/wh_buy/Usa/Amplifier.html Plenty of choices. Some are even Class D amplifiers that don't waste power generating much heat. I've ordered from here before, never had a  problem, but delivery sometimes takes a while, especially if the item comes directly from China instead of the US Warehouse. I think all these items are in the US warehouse. --Mike, WV2ZOW
  • Norm - W7CK
    Norm - W7CK Member ✭✭
    edited February 2017
    What voltage is your off-grid battery bank?  Mine is a very small 12v dc home-built system.  I have 4 140w panels into a charge controller which charges the 12v battery system made up of 4 golf cart batteries.   Its mostly to run my ham shack, computers, etc.

    One issue I have is the fact that if I attach equipment directly to the battery bank, the voltage can vary quite a bit.  Especially during the day when the charge controller is going full bore!   15v is the max I've ever seen, but that is still more than most of these little amplifiers are rated for.

    What is the voltage range you see from your solar system?
  • Jim  KJ3P
    Jim KJ3P Member ✭✭
    edited June 2020

    You might try a Lepai LP-2020A+ amplifier.  These are amazing little boxes...I've had one driving a pair of large Advent speakers (!) in the TV room for two years.  Awesome sound for such a small inexpensive device.  About $26 on Amazon.

    Never any RF problems here, but of course all RF situations are not created equal.

       --jim KJ3P

  • Ken - NM9P
    Ken - NM9P Member ✭✭
    edited December 2016
    I used one of those Lepai 2020+ amps to drive a pair of Dayton AUdio bookshelf speakers.  They sounded good, but since my vertical was just outside my window at the time, I had some RFI problems that numerous Ferrite beads didn't solve.  So I changed to a set of Bose Companion 2 Series 3.  I really like these!  they also have dual simultaneous inputs so I can connect my computer on one input and the 6500 on the other...no switching required.

    I did find that I had a ground loop problem that was fixed by a $9.95 stereo ground loop isolator, which is essentially two audio transformers that isolate the ground leads between the amp, the computer, and the 6500.

    Someday I will try the Lepai/Dayton Audio combination again using the ground loop isolator and see if that works.

    Ken - NM9P

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