For Sale PCBs for Super Mofo (with pucks) and for a high current filter + negative rail generator

[schultzsch]

Hello,

I have for sale the pcbs for an improved version of the Mofo and the pcbs for the power supply for it.
This one has better bias control, better high frequency performance, doesn’t need a low output impedance preamp to drive it so you can easily use valve preamps too.
There is another interesting part, the power supply which generates a negative rail through an isolated dcdc converter which gives the posibility to use SITS without worrying about the inductor’s resistance when biasing the transistor.
Both the positive rail and negative rails are filtered giving very low noise.

2x amp pcbs + 2x ps pcbs 40€
2x IXFN280N085 50€

 

[ggetzoff]

Fantastic work! Did you do this?? Did I miss this thread some how.....

I'm interested.

 

[schultzsch]

Thanks.
No, the amp is ZM’s Warbler. The power supply is Mark’s design, the AmyAlice to which I added a cap multiplier and it became A2Cmx. To the A2Cmx I added an isolated dcdc converter to be able to get a negative voltage from the positive rail and it became A2Cmx-V(which I shown in this sale thread)

I published something in the Warbler thread for the amp.
For the A2Cmx(without the new added part) I created a dedicated thread when I developed that pcb.

 

[schultzsch]

I have added a thd measurement at 25W/8r to show what the amp can do if you have the appropriate cooling.

 

[ggetzoff]

Did you do a 4R load plot?

 

[schultzsch]

I attached a few to the first post

 

[schultzsch]

Today I managed to get a bit more voltage out of my preamp and got to 33W on the output of the amp into 8r. I did 3 measurements where you can see that at 3.8A the higher order harmonics raise more than at 3.6A which indicates that 3.5-3.6A would be a maximum for the choke. Added the attachments to the first post.

 

[ggetzoff]

Very cool. You’ve done an amazing job with this. 4R load looks good with distortion products all the way up, nice stair step from H2 onwards.

I guess you better send me a set. Battery powered Tokin amp!

 

[ggetzoff]

I just got this linestage and I love it. First line stage I’ve ever had that is truly “wire with gain” yet natural sounding. Swings huge p-p vac.

https://www.schiit.com/products/kara

 

[schultzsch]

Thanks Greg.

Looks nice and cheap too for the offered performance. It opens a lot of roads if I can say so.

 

[ggetzoff]

Lucian, the Kara preamp is a game changer for sure with the p-p swing and how transparent it is.

 

[schultzsch]

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