Audio Innovations 6b4g monos

Up for sale these great sounding mono amps from Audio innovations These have been sitting around doing nothing for yrs stopped using them when i brought a Border patrol SE300B.They are fully working.
I do not know very much about them to be honest so maybe someone can tell me.I used to use them bi-amped with a 1st Audio to drive a pair of Audio note speakers.Not sure what they are worth.But would be happy with £600.00 collected.Can post more pics if anyone is interested.


I’ll take these please?


Not sure what the particular paint finish is all about.Originally a few pairs of these were made (in the S800 chassis) while the company was waiting for the stereo chassis that the First Audio eventually went into.

These used the S300 power transformer and a Savage output transformer but were based on the same circuit that eventually was used in the stereo version. Quite high input sensitivity although it’d be relatively easy to attenuate the input if a higher gain linestage was being used.


Paint job was done by the previous owner you ether like it or hate it.I also still have the 1st Audio but liked the 6b4g a bit more, seemed to have a sweeter mid and top.Need to do some work on the 1st audio before selling as its the octal 2a3 but one of them has died.

I was also interested to see the other ones listed in the ebay thread which appear to have C core power transformers fitted & wooden sleeves.

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Yes i saw them they look interesting looks like valve rectifier has been added as well,would like to hear them to see how they sound. If i had kept using mine i did intend to do them up with a nice wooden case,but the Border patrol came along.

They were mine, you fixed them up for me!

I think I sold them to Tom, who got the wooden chassis built, possibly by Russ C.


Now sold thanks