Bottlehead Forum

Bottlehead Kits => S.E.X. Kit => Topic started by: ssssly on June 03, 2010, 02:11:21 AM

Title: Replacing Rpsu with stock plate chokes?
Post by: ssssly on June 03, 2010, 02:11:21 AM
I am in the process of building a SEX amp with the MQ upgrade iron and C4S and have been looking for something to do with the stock plate chokes.

After reading this post http://www.bottlehead.com/smf/index.php/topic,160.0.html I am leaning toward replacing Rpsu with the stock plate chokes.

Is there any conceivable reason that this would be a bad idea?



 
Title: Re: Replacing Rpsu with stock plate chokes?
Post by: tbbenton on June 03, 2010, 03:20:21 AM
Is there any conceivable reason that this would be a bad idea?
From my limited experience, I'd say watch your placement so you don't introduce hum.
Title: Re: Replacing Rpsu with stock plate chokes?
Post by: Dyna Saur on June 03, 2010, 03:29:11 AM
The stock plate chokes have a somewhat higher DC resistance (around 768 ohms) than the stock Rpsu, but the slight voltage drop (around 4VDC) should not be a problem. Just finding space to mount them under teh chassis, after the upgrade may be a bit of a daunting task.   AS mentioned previously, just be careful that their placement doesn't introduce any unwanted inductively (magnetically) coupled hum problems.   

Or, use them (as I did) in a homebrew parallel feed small SET amp design.

/ed B in NC
Title: Re: Replacing Rpsu with stock plate chokes?
Post by: Paul Joppa on June 03, 2010, 11:42:48 AM
Check the "Hammond choke" thread under Seduction for another application of those old SEX plate chokes....
Title: Re: Replacing Rpsu with stock plate chokes?
Post by: ssssly on June 03, 2010, 04:56:45 PM
The shunt reg does sound like an interesting idea. However, I must say, designing it from scratch to fit the circuit is a bit above my knowledge level.

If someone would walk me through it I'd be more than happy to build it and report back how it sounds though :)
Title: Re: Replacing Rpsu with stock plate chokes?
Post by: Paul Birkeland on June 03, 2010, 05:31:10 PM
The shunt regulator in the SEX circuit isn't the greatest idea, as the current headroom in the power transformer just isn't there.