100W Ultimate Fidelity Amplifier

[still4given]

thank you, disturb you tell me the value of 2 transistors

The schematic says BD241, BD242. I used MJL15030, MJL1503. Please check post 8917. There is a missing connection in your layout

 

[xrk971]

Sorry for not getting it - but where does the pot selector drive circuit connect to the above analog switch circuit?
Thanks.

 

[apexaudio]

Sorry for not getting it - but where does the pot selector drive circuit connect to the above analog switch circuit?
Thanks.

You must use array of 3 audio switch and connect 120k to BC337 colector instead to gnd switch. Outputs from 3 audio switch connect in parallel (3 left and 3 right).

 

[apexaudio]

Greetings mr.apex sir
Pls share audio switch with 4066 ic crcuit

You can find many circuits with 4066 on the net.

 

[sownel]

You must use array of 3 audio switch and connect 120k to BC337 colector instead to gnd switch. Outputs from 3 audio switch connect in parallel (3 left and 3 right).

Greetings mr.apex sir
Pls share ic switch with cd4066

 

[xrk971]

Sorry for not getting it - but where does the pot selector drive circuit connect to the above analog switch circuit?
Thanks.

 

[apexaudio]

Sorry for not getting it - but where does the pot selector drive circuit connect to the above analog switch circuit?
Thanks.

 

[pinnocchio]

Got my P30zf PCB from the fab

They look good!

Do

 

[still4given]

Nice!

 

[xrk971]

Apex Audio,
Thank you!

 

[apexaudio]

Got my P30zf PCB from the fab

They look good!

Do

Nice pcb, look like you will be first to test this pcb.
Regards

 

[pinnocchio]

Nice pcb, look like you will be first to test this pcb.
Regards

Hi Mile,

Since you're the designer of the circuit and Alex of the PCB, I'd like to offer you both a free set. Just PM me your postal address and I will send you.

Thanks!
Do

 

[apexaudio]

Hi Mile,

Since you're the designer of the circuit and Alex of the PCB, I'd like to offer you both a free set. Just PM me your postal address and I will send you.

Thanks!
Do

Thank you, Olaf made and test P20 preamp with same topology and this P30ZF is final version.
Regards

 

[thimios]

Got my P30zf PCB from the fab

They look good!

Do

Amazing!

 

[mprivitera1]

pream apex P30

Hello guys,

a question for pream apex P30, I can put BC550C for it?
Thank you

 

[erik777]

Let us know how it compares to the other pre amps you have. Looks nice

Got my P30zf PCB from the fab

They look good!

Do

 

[gaborbela]

Let us know how it compares to the other pre amps you have. Looks nice

 

[Hadighorbani]

Audio switch with transistors.

hi
do you test this one swich?
is this worked perfect without bad quality in output sound?

 

[xrk971]

hi
do you test this one swich?
is this worked perfect without bad quality in output sound?

I am thinking of building this on veroboard to test out. BC550/560's are some of the finest small signal BJT's used in many state of the art low-noise, low-distortion pre-amps so I suspect they do not degrade the signal when used correctly.

I wonder if a LED and 4.7k in series resistor can be used to give visual indication of which switch is active?

 

[AndrewT]

You may find that jFETs work better for switching duty.

There was a Thread some years ago in which was mentioned an alternative switching arrangement that eliminated the distortion due to any non linearities across the switch.
I wish I could remember these things !