Mesa Boogie - Throttle Box  [schematic]

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Re: Mesa Boogie - Throttle Box

Postby Dirk_Hendrik » 08 Jan 2019, 15:59

FloPoeKo wrote:The coil in the pictures pretty much looks like the ones they put in the amp-eq-sections,
Any thoughts?



Are you sure? ;-)
http://www.coilws.com/index.php?main_pa ... th=208_291
Sorry. Plain out of planes.

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Re: Mesa Boogie - Throttle Box

Postby Ricotjuh » 08 Jan 2019, 19:00

temol wrote:
FloPoeKo wrote:On the Inductor:

Are we 100% sure it is 250mH and not 220mH?


here is a plot from ltspice simulation. With 250mH you have 678 Hz, with 220mH - 720 Hz and with 200mH - 760 Hz.

Lsweep.jpg

T.


Would the difference of 42Hz give an audible difference?
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Re: Mesa Boogie - Throttle Box

Postby temol » 08 Jan 2019, 22:00

Even if the difference is audible, does it matter? :)
I think that the problem is the availability of coils with such a high inductance, not the difference of a few Hz.

T.
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Re: Mesa Boogie - Throttle Box

Postby FloPoeKo » 09 Jan 2019, 20:09

Dirk_Hendrik wrote:
FloPoeKo wrote:The coil in the pictures pretty much looks like the ones they put in the amp-eq-sections,
Any thoughts?



Are you sure? ;-)
http://www.coilws.com/index.php?main_pa ... th=208_291
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Re: Mesa Boogie - Throttle Box

Postby FloPoeKo » 09 Jan 2019, 20:12

OK, I think I will give it a shot and make an inductor. From what it looks, I can make it as small as 12x12mm for the footprint and 10mm in height. The pitch would likely be 7,5mm and 5mm with three pins, one can be snipped of depending on the lead pitch will be used. It will be a pot-core, not toroid though.
I´m open for any kind of suggestions.
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Re: Mesa Boogie - Throttle Box

Postby PLUT0music » 25 Jan 2019, 02:11

I see a lot of talk about the big 250mH inductor. Anybody ever had the idea, instead of using this gyrator with an actual inductor, to use the leftover opamp and building another gyrator like in the EQ?

So far i didn't build it yet either, but I did put it into my simulation program to see, if it could work.
And I got pretty close, not ideal though.

Any thoughts on that?
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Re: Mesa Boogie - Throttle Box

Postby for.try.soft » 01 Mar 2019, 13:24

According to this calculator (http://sim.okawa-denshi.jp/en/RLCbpkeisan.htm), when you move MidCut pot, you change Q of the bandpass filter from 0.1 to 10. So, it can't be done by using simple gyrator instead of coil bandpass filter.
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Re: Mesa Boogie - Throttle Box

Postby Ricotjuh » 14 Jul 2019, 20:44

For the tone potentiometer, a 20K potentiometer is required. However, I can only find a 20K W-taper that is also used with a Tubescreamer. Can I also use this for this? Or do I have to go to a 25K version?
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Re: Mesa Boogie - Throttle Box

Postby Dr.Detroit » 15 Jul 2019, 22:49

Ricotjuh wrote:For the tone potentiometer, a 20K potentiometer is required. However, I can only find a 20K W-taper that is also used with a Tubescreamer. Can I also use this for this? Or do I have to go to a 25K version?


The tone control here works the same way the Tubescreamer tone does, so a 20k W-taper should be fine.
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Re: Mesa Boogie - Throttle Box

Postby Ricotjuh » 15 Jul 2019, 23:10

Ok, thanks for your reply
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