Burning Amplifier BA-1

[Jason]

Thank you. Yes, credit card support is not something that is made very obvious by paypal. I will see what I can do to ensure it's made more clear that Visa and Mastercard work just fine!

[tinitus]

Its very easy
Send a money request through paypal
All a buyer needs is an approved credit card
It takes about 5minutes the first time
Its also the best way to avoid sending money to a wrong email account

[Jason]

Gotcha. Thanks. I've now updated the store and it should be very clear now how to pay with a CC. Cheers.

[Gyuri]

Yesterday I got the boards:

BA1&BA2 - Windows Live

Thank you for all you guys!
I do not know when these boards will be ready amplifier.
Indeed, while somewhat unexpectedly robbed me.
The tax office was the culprit.
I am slightly underestimated their expected prey.
So, not only that I had no money, but a substantial debt was incurred.
While we practically destitute.
But at least the outgoing government will be sufficient severance pay.
Then, we earn the next. :
I do not know, this was just now the forbidden politics?

Gyuri

[Tea-Bag]

Well, I got the follower up and running with two FET's. Seemed pretty simple to get rid of DC offset like this, but I didn't have it powered up too long.

Well and without the gain board there is not much gain.

[Tea-Bag]

I think lowering C203 will act as a high pass filter. But I am unsure of the Resistor value associated with it, possibly R14. I was shooting for 180-200hz for my lowthers.

Popped a Semisouth into the Q101 position, and was able to stablize bias with the fixed Q102 .6v.

Time to get a front end built.

[generg]

SOS...........SOS,

on the new frontendboard of BA1 and BA2 the marked polarity of C205 and C206 is wrong, the caps get hot. You must change the polarity!!!!!!!!

Please could anybody confirm my experience?

SOS....SOS...

[cviller]

Thanks for pointing out this error. But it is not the caps, but the supplies that are marked wrong see attachment.

[generg]

Originally Posted by cviller

Thanks for pointing out this error. But it is not the caps, but the supplies that are marked wrong see attachment.

Thanks I just remarked the same!!!!!!!


because the caps got hot again,ha ha!

[generg]

.....some news building BA-1!

My outputstage is only 3 devices deep, so I took 0,47 Ohm as a source resistor.

The voltage over the source resistor must be in my case only 0,3 Volt?
To get the bias current down, I had to start at 22 k with R 219 instead of 47 k.

I had some difficulties when setting the amp under fire, for instance I could not regulate the DC output to 0 Volt.
Later I remarked the holes to fasten the board have a very small distance to the voltage rails. My metal screws and the counterpart shortened something.
I would suggest for the second version of the boards to enlarge the distances or .... you use nonmetal parts to fasten the board.

The sound? (only the outputstage driven by pumpkin directly):

very good! really still better than F4 in many aspects, but less dynamics! (hi ZenMod)

4 Ohm loudspeaker! Mister Nelson was right, sonically more pure, but more suited for impedances at 8 Ohm.

Nevertheless I will hear the next days BA-1! Returning to F4? Don´t know yet!

Maybe J2 is coming?