Bottlehead Forum

Bottlehead Kits => Legacy Kit Products => Seduction => Topic started by: xcortes on August 11, 2010, 08:40:10 AM

Title: Shunt reg Mono Seduction
Post by: xcortes on August 11, 2010, 08:40:10 AM
My mono system is (Finally!) materializing. I just purchased a large lot of mono lps and a very nice field coil speaker from the Third Reich.

I have a Seduction that will use for the system but since I will only be using one channel I'd like to shunt regulate it. I'm looking for ideas on where to look at or how to implement it.

Thanks
Title: Re: Shunt reg Mono Seduction
Post by: 2wo on August 11, 2010, 12:57:22 PM
PB posted a while back about using a gas reg  tube, something I want to try.

I would thing that with only one channel there might be enough transformer capacity to run a shunt reg, if managed carefully maybe move the filament load to another transformer or wall wart. If you have a Foreplay II you could study it
Title: Re: Shunt reg Mono Seduction
Post by: Grainger49 on August 11, 2010, 01:26:35 PM
There is some voltage lost with a gas regulator like through the 10k 15W resistor in the FP III.  Hopefully changing the power supply from the Pi filter would give you that voltage.  If not a voltage doubler like the FP III might give it to you.
Title: Re: Shunt reg Mono Seduction
Post by: Doc B. on August 11, 2010, 07:12:27 PM
Gas reg heater current? Does not compute.
Title: Re: Shunt reg Mono Seduction
Post by: Paul Joppa on August 11, 2010, 08:18:51 PM
Should be quite possible; just convert one channel to dual shunt regs. Do you already have the C4S upgrade for your Seduction?
Title: Re: Shunt reg Mono Seduction
Post by: xcortes on August 12, 2010, 02:05:37 AM
Quote
Do you already have the C4S upgrade for your Seduction?

Yes I do!
Title: Re: Shunt reg Mono Seduction
Post by: Paul Joppa on August 12, 2010, 07:46:59 AM
Quote from: xcortes on August 12, 2010, 02:05:37 AM
Quote
Do you already have the C4S upgrade for your Seduction?

Yes I do!

Too bad, the connections are going to be a puzzle. The idea is simple - use one 6922 as a dual shunt reg, keeping the other as the RIAA amp. But you would need four independent current sources, and the existing board has a single input and only two bias chains. And the newest PC boards do not quite fit the screw spacing of the current Seduction.

Let me think about the possibilities for a couple days, and ping me privately. As long as you do not need the cover shield box, I'm sure we can cobble something together.
Title: Re: Shunt reg Mono Seduction
Post by: Doc B. on August 12, 2010, 08:03:59 AM
IIRC some Seduction chassis panels actually got made with additional holes for the green SRC4S style PC board near the nine pin socket holes. I don't have any specific info about when or where these might turn up, I just know that there are some out there.