My Sigma Build
Hi all,
Thanks to Dr Bora's advices, I have completed my Sigma Lateral-MOSFET amplifier and had been listening to it for a couple of weeks. I am impressed with the sound quality and it is one of best amplifiers that I have listened to on my home setup.
The bass is tight and controlled; the vocal is sweet & clear and the high is detailed. Overall the amp is musical and it does not exhibit any harshness at any frequency. I love the sound of this amplifier.
I used the Sigma schematics as published on :::Borina Amaterska Svastara:::
I used the recommended semi devices as detailed in the schema & I made my own PCB.
My supply voltage is 63V
I biased the output MOSFET to 100mA
The amp is dead quiet with no hiss or AC hum.
There is no turn-on or turn-off thumps.
I used an old E-I core transformer & the acoustic noise from this transformer is the most annoying source of noise of this build.
Cheers, Stanley
Hi all,
Thanks to Dr Bora's advices, I have completed my Sigma Lateral-MOSFET amplifier and had been listening to it for a couple of weeks. I am impressed with the sound quality and it is one of best amplifiers that I have listened to on my home setup.
The bass is tight and controlled; the vocal is sweet & clear and the high is detailed. Overall the amp is musical and it does not exhibit any harshness at any frequency. I love the sound of this amplifier.
I used the Sigma schematics as published on :::Borina Amaterska Svastara:::
I used the recommended semi devices as detailed in the schema & I made my own PCB.
My supply voltage is 63V
I biased the output MOSFET to 100mA
The amp is dead quiet with no hiss or AC hum.
There is no turn-on or turn-off thumps.
I used an old E-I core transformer & the acoustic noise from this transformer is the most annoying source of noise of this build.
Cheers, Stanley
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I am very happy for you and glad that it fulfilled your expectations! That is an excellent amp of higher class range and you won’t be ashamed to power it next to most brand name amps!
Thanks for your trust and devotion.
Bora
Thanks for your trust and devotion.
Bora
DR Bora, sir,
i am interested with that X-Over, if you have the design of all this 3Way X-Over, may i have the PCB layout and Component Layout, i wanna make it for tone control (the output will get together as just one output), is that ok, i hope you can give me some sugestion on that modification, please.
thank you sir.
You can have PCB and layout files for 3Way X-over if you mail me on my direct E-mail.
I am not sure that I understand what you are going to do because that is not a tone control and there is no point of joining together outputs from this module!? This unit should go after some kind of preamp (with or without tone control) and outputs should go to 3 separate power amps to drive three separate drivers in 3 Way Box to avoid passive crossover.
I am not sure that I understand what you are going to do because that is not a tone control and there is no point of joining together outputs from this module!? This unit should go after some kind of preamp (with or without tone control) and outputs should go to 3 separate power amps to drive three separate drivers in 3 Way Box to avoid passive crossover.
You can but it is very likely that you will have problems with stability! IRFP260 WOULD NOT give you more power as you think. You can change any component in any design if you want or think it is better for you, but then don't blame design or designer if you fail!
Attachments
This is a PCB common for both Legend BASIC and Legend Stage Master. If you pay attention you will notice that there are same unused positions for additional output devices to allow upgrade later if you need that.
thank u victor for this pcb.
is this new version or old version?
did u made this amp?
how many watts for this amp?
what is maximum voltage of dc?
there are two pots in this pcb and i think one is for bias and other one is for dc offset am i correct.
how to adjust these pots pls explain.
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