Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: Leevi on March 10, 2012, 03:36:10 pm

Title: SS choke
Post by: Leevi on March 10, 2012, 03:36:10 pm

Does anyone have experience/comments in SS choke?

http://www.ebay.de/itm/Elektronik-Drossel-Mosfet-Gyrator-Solid-State-Choke-/110646193972#ht_3649wt_962 (http://www.ebay.de/itm/Elektronik-Drossel-Mosfet-Gyrator-Solid-State-Choke-/110646193972#ht_3649wt_962)

/Leevi

Title: Re: SS choke
Post by: PRR on March 10, 2012, 03:54:43 pm

No energy storage.

A real choke, if the load current is cut-off, the choke voltage will kick-up above the supply voltage.

This can only kick-up a couple volts, not even to the supply voltage.

It will kill ripple buzz. It may not have the guitar dynamics of a real choke.

2 bucks. Try it.

Title: Re: SS choke
Post by: Leevi on March 10, 2012, 04:55:24 pm

Quote

2 bucks

That is just an empty board. A complete choke costs some more:

http://www.ebay.de/itm/Elektronische-Drossel-Mosfet-Gyrator-SS-Choke-200mA-/110794732851?pt=LH_DefaultDomain_77&hash=item19cbe17533#ht_3435wt_962 (http://www.ebay.de/itm/Elektronische-Drossel-Mosfet-Gyrator-SS-Choke-200mA-/110794732851?pt=LH_DefaultDomain_77&hash=item19cbe17533#ht_3435wt_962)

Leevi

Title: Re: SS choke
Post by: kagliostro on March 10, 2012, 05:36:57 pm

Merlin explain how to calculate this kind of choke in his PS Book

Gyrator (http://en.wikipedia.org/wiki/Gyrator)

Kagliostro

Title: Re: SS choke
Post by: jazbo8 on March 10, 2012, 08:04:30 pm

I have not tried the gyrator yet, but it seems more suitable for plate load application, as PRR already hinted at, also see http://www.diyaudio.com/forums/tubes-valves/183476-electronic-choke-3.html#post2475782 (http://www.diyaudio.com/forums/tubes-valves/183476-electronic-choke-3.html#post2475782), in any case, nothing beats actual testing, has anyone tried using it as replacement choke in the power supply?

Jaz

Title: Re: SS choke
Post by: jjasilli on March 11, 2012, 09:15:37 pm

This is new to me, but I googled this:  http://www.antiquewireless.org/otb/resto0504.htm (http://www.antiquewireless.org/otb/resto0504.htm)

Seems to me this is not a choke but rather a voltage regulator. Voltage regulation will suppress ripple and other noise.  But as PRR points out, it lacks the reactance of a choke. 

Title: Re: SS choke
Post by: Leevi on March 12, 2012, 09:58:41 am

I ordered couple of units, let's see how it works.
Anyway it's lighter and cheaper than a real choke.
/Leevi

Title: Re: SS choke
Post by: Leevi on March 21, 2012, 01:03:13 pm

I installed one board in an SE amp and placed it after the rectifier and first filter cap
and took B+ from the output of the device i.e. all current needed by the amp goes
through the "choke"-circuit.

I didn't notice any difference in the sound. Maybe it eliminated some hum.
Probably this is more beneficial in the amps where the hum level is higher.

/Leevi

Title: Re: SS choke
Post by: jazbo8 on March 21, 2012, 06:57:20 pm

Try putting it (or them) on the plates of the pre-amp and PA driver, where it should have a more dramatic effect. Please keep us posted on your experiment.

Thanks,
Jaz