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devilsindetails 17th November 2011 01:17 AM

HELP! Capacitor specs for Sonic Frontiers SFC-1 Control Amplifier
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Hey Gang....I have a Sonic Frontiers SFC-1 Control Amplifier (4x EL34, 1x12AT7, 2x12AU7) that requires new main caps (circled in red on the attached pic).

While I have the voltage specs for these (450v) I have no idea how many uF.

There are no spec markings on the exterior of these huge can caps, save for a manufacturing number of 658 9302 319.

Anyone out there have any experience with these. Lots of owner's manual information but no service manual or schematics.

Thanks Leo

speakerfritz 17th November 2011 05:37 PM

hi, may I ask what makes you say it needs new main caps?

devilsindetails 17th November 2011 06:29 PM

Gets the typical "thump" at speaker output after startup delay (signal output for five seconds) and then thumps again cutting out one channel, then another thump cutting out the other channel.

That seems to tell me the caps are energizing and discharging too quickly on startup and then losing whatever capacitance they have entirely. Yes ? No?

steven2583 17th November 2011 06:55 PM

Call or email a tech at Parts Connexion. They do mods on the Sonic Frontier units.

devilsindetails 18th November 2011 02:32 AM an e-mail from Chris Johnson but these caps remain a bit of a mystery...they are guessing somewhere between 1200-1500 uf at 350 volts but as these puppies will be tres-expensive I would like something a little more definitive. I know I can up the voltage capacity without any harm but the uf ratings would seem to be more critical to determine exactly.

ticknpop 18th November 2011 02:47 AM

The cap value in uf isn't critical 1200-1500 uf range is fine. These caps would be less than $20.00 each at Digikey. I'd do the rest of the smaller electrolytics at the same time. Try to find a 105 C cap for longer life of the same value and physical diameter. Panasonics are a good bet.

devilsindetails 18th November 2011 03:02 AM

Thanks..when you say 105c are you talking about the temperature rating?

Braga 25th January 2012 04:35 PM

They look exactly the same as the SFS 40 power amp. main caps.
Value is 1700uF/300 V x 2 in series.

DF96 25th January 2012 05:26 PM

Sounds more like protection circuitry than reservoir caps.

Jebem 25th January 2012 09:40 PM

Try Anthem - I believe they own the old Sonic Frontiers brand.
About Anthem - Welcome to the New Official Anthem® Audio Video Website.

they have the operator manual for download as well:

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