Solid state phase inverter?

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azatplayer
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Solid state phase inverter?

Post by azatplayer »

Anyone had a go at using mosfets for phase inverting?
Reading and about to try some curious implementation of fets as followers. Will report what i hear, but im also interested in phase inverter use as well.
I think as long as theyre not used where usable gain is being made, they could be very useful, both cheap to obtain and last forever, as well as accurate reproduction of preceding stages.
Maybe heresy, but who's afraid of a little fire ;)
printer2
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Re: Solid state phase inverter?

Post by printer2 »

I would think being able to replace the cathode follower with a mosfet source follower means the Cathodyne should be no problem.
teemuk
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Re: Solid state phase inverter?

Post by teemuk »

Blackstar (HT-series) amps do it. They use a MOSFET LTP with a constant current source tail. The earliest Vox Valvetronix amps also had a MOSFET PI before the 12AX7 power amp emulation stage. I think I've seen a few others too but can't remember what they were.
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Structo
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Re: Solid state phase inverter?

Post by Structo »

You will be banned from the forum if you use any semiconductors in the signal path. :shock:


J/K but why do you want to replace tubes with silicon?
(which have a crystal lettuce structure) :P
Tom

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JazzGuitarGimp
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Re: Solid state phase inverter?

Post by JazzGuitarGimp »

Structo wrote:but why do you want to replace tubes with silicon?
(which have a crystal lettuce structure) :P
Shouldn't we be using the TLA (three letter acronym, which is a TLA in its own right...) 'CLS' for this term? :lol:
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LeeMo
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Re: Solid state phase inverter?

Post by LeeMo »

Music Man used a CLS (Mosfet) PI in their amps.
http://www.freeinfosociety.com/electron ... php?id=560

LeeMo
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LeftyStrat
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Re: Solid state phase inverter?

Post by LeftyStrat »

In addition, don't forget the transformer PI.
It's never too late to have a happy childhood.
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Reeltarded
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Re: Solid state phase inverter?

Post by Reeltarded »

I used to watch transformer PI. I loved that show. His friend with the helicopter and that english guy on the estate and he would look like a 308 and drive around then turn into a robot.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
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LeftyStrat
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Re: Solid state phase inverter?

Post by LeftyStrat »

Reeltarded wrote:I used to watch transformer PI. I loved that show. His friend with the helicopter and that english guy on the estate and he would look like a 308 and drive around then turn into a robot.
Though having a mustache on a transformer can get pretty stinky, especially if you don't wash out the food particles.
It's never too late to have a happy childhood.
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Reeltarded
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Re: Solid state phase inverter?

Post by Reeltarded »

The local tea club connection to the king of a place you never heard of will be the foil.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
azatplayer
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Re: Solid state phase inverter?

Post by azatplayer »

I loved that show too, never did like much he did after it tho.
Timvox1
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Re: Solid state phase inverter?

Post by Timvox1 »

azatplayer wrote:I loved that show too, never did like much he did after it tho.
Blue Bloods is a pretty good show.
stephenl
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Re: Solid state phase inverter?

Post by stephenl »

I played around with an LND150 as a cathodyne, it worked very well. You just have to design it so it doesn't get overdriven. It was completely transparent to my ears.

In my case, I used it to feed both inputs of a LTPPI, ala Marshall Major, to drive the PA harder.
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rp
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Re: Solid state phase inverter?

Post by rp »

Structo wrote:J/K but why do you want to replace tubes with silicon?
(which have a crystal lettuce structure) :P
Go to the local library and do a search, tubes are finished, this transistor thing is going to change everything. Soon everyone will have personal computers the size of an attache case and you'll be able to use a payphone with a credit card!
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Structo
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Re: Solid state phase inverter?

Post by Structo »

Hehehe, I remember in school many moons ago that soon paper money won't exist and they we would all use a plastic card to make purchases.

We just shook our heads at the absurdity of it. :D :shock:
Tom

Don't let that smoke out!
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