Hybrid Circlotron Amplifier with only 3 components on the signal path

[audiodesign]

Hybrid better than SE vacuum tube amp. ?

Look my simple design in testing phase

Hybrid Amplifier by Andrea Ciuffoli

[DF96]

The "signal path" is a concept which, as normally used, is meaningless. I can see at least 8 components which could affect the signal, quite apart from the power supply.

[banat]

Originally Posted by audiodesign

Hybrid better than SE vacuum tube amp. ?

Look my simple design in testing phase

Hybrid Amplifier by Andrea Ciuffoli

Cool & Elegant Hibrid Circlotron Amp Design

Go Forward

[audiodesign]

Originally Posted by DF96

The "signal path" is a concept which, as normally used, is meaningless. I can see at least 8 components which could affect the signal, quite apart from the power supply.

This is true!

I am considering only the main components: tube, interstage transf. and mosfet.

If I compare this project to others this is a not common design, also my PF2007 system is more complex because need the output capacitor.
PF2007: the system

I see as large influence in the sound the cathode capacitor that I cannot eliminate but it can be considered an advantage because you can use it to modify the sound.

Some candidates are:
1) Sanyo OS-Con - very neutral but a little bit too hard
2) ELNA Cerafine - very smooth, good to lay normal CD
3) ELNA Silmic II - less smooth of Cercafine but still too much

In my last GM70 SE dc coupled
GM70 amplifier with Fiat transformers
I have got a good benefit using a led ( in the optocoupled) instead of cap/res. on cathode but here I cannot apply it because the low frequecny band will be too much compromised.

[hidnplayr]

Nice work!
I have been wanting to build something like this using BUZ901's and 2xECF80 in a long tailed pair, with cathode followers.

[audiodesign]

In my test 2SK1058 are much better than BUZ900P.

[audiodesign]

In my test 2SK1058 are much better than BUZ900P.

The minimum distortion with BUZ900P is at the bias point 30V DC and 900mA at any output level.

Using the 2SK1058 the minimum distortion is at the bias point 30V DC and 1600mA and the level is 60-70% less than BUZ with the same input stage.

You cannot use IRF types and 2SK1529 because these need a thermal compensation circuit.

[audiodesign]

I am tesing soon the new Profusion lateral mosfet to reduce output impedance.

Profusion plc, Audio Semiconductors and Components

The final chassie will be HiFi-2000 H=210mm

The power supply probably will be increased to 40V DC.

[tympani1d]

Will boards and kits be available?

[audiodesign]

yes, probably a pcb will be necessary for the protection circuit and filaments-bias power supply.

I think will be possible also use protection modules available on Ebay.

A complete set of all parts and shop will be available.