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AD Audio
27-06-2020, 10:36
https://i.imgur.com/q0uXmlD.jpghttps://i.imgur.com/keLVkNk.jpg It's been a while coming but I took a week off my regular audio work to build myself a Radford sta100 as a pair of monoblocks. These are signature amps with a lot of foo inside including Black gate capacitors and Audyn true copper caps. They are point to point wired and the transformers are specced to take KT150s or KT120s, both of which thrive off the high HT of 630v and high screen voltage. The KT120s sound much better to my ears, suiting the output transformers better.

So how do they sound? I'm fortunate enough to own a pair of Silvercore 833 monoblocks and my wife has a pair of Mastersound 845 monoblocks and this amp shows both of these a clean pair of heels. It's got effortless scale and majesty, and sounds very sweet across the whole frequency range. I'd like to thank Will at Radford Revival for help and advice along the way and for speccing and supplying the transformer sets. The output transformers are rated at 100 watts continuous output. Now here's a pair of amps that will drive any Tannoys! I'm open to building some more of these or even a stereo version......

tapid
27-06-2020, 11:08
Nice one David. Sure looks splendid and I m sure sounds the same. You could even rename it the A D Ford

AD Audio
27-06-2020, 11:15
Nice one David. Sure looks splendid and I m sure sounds the same. You could even rename it the A D Ford

:):)

WESTLOWER
27-06-2020, 11:24
Had the pleasure of a dem on these yesterday.
I run an STA25 at home and these have the sweetness of the original STA range but have the power and
effortless push in abundance. These are very exciting amplifiers indeed.
Well done David a real accomplishment.

options, options....

http://i.imgur.com/0HYylD0.jpg (https://imgur.com/0HYylD0)

AD Audio
27-06-2020, 12:42
For those who like to look under the boinnet. This was before a wiring tidy up but you'll get the picture.......https://i.imgur.com/nbaAeOb.jpg
The amps are completely silent in operation.

flapland
27-06-2020, 13:21
Looks very interesting David. If you ever decided to tri-amp the speakers you could retire your Central Heating boiler.

AD Audio
27-06-2020, 13:25
Looks very interesting David. If you ever decided to tri-amp the speakers you could retire your Central Heating boiler.

:):):)

Sherwood
27-06-2020, 14:58
I am sure that these sound awesome but is there a reason for one of the transformers being at a slight angle? It seems that you have a nut under the flange of one transformer.

Out of interest, what would a pair of these cost?

AD Audio
27-06-2020, 15:47
I am sure that these sound awesome but is there a reason for one of the transformers being at a slight angle? It seems that you have a nut under the flange of one transformer.

Out of interest, what would a pair of these cost?

The eagle-eyed among you may have noticed there's no knobs either at that time :):) The transformers are mounted on silicon blocks. Cost is really determined by the chassis. I used my last Cannonball chassis from that production run for these but think around £4,500 and it won't be far out.

Audio Al
27-06-2020, 16:10
The eagle-eyed among you may have noticed there's no knobs either at that time :):) The transformers are mounted on silicon blocks. Cost is really determined by the chassis. I used my last Cannonball chassis from that production run for these but think around £4,500 and it won't be far out.

I'm here :D

Serious amp building going om here :)

AD Audio
30-06-2020, 06:35
If anyone is interested in following up re pricing, a build etc please send me your e mail address by Pm and I'll add you to the group info and follow up offline
David