On the website it looks like balanced with two unmodulated current sources and the speaker clamped in between. I also heard it at Lemgo and it sounded good. The speakers ( Dieters new horns ) where unfamiliar though.
Yes, i prefer class a or tubes. They simply sound much more grainless and sweeter.
It may be the higher harmonics plus IM. Also a lot of super low distortion, high feedback amps do not like to drive a real speaker. There are intersting measurement in the new Streoplay that scratch a bit on the surface.
Yes, i prefer class a or tubes. They simply sound much more grainless and sweeter.
It may be the higher harmonics plus IM. Also a lot of super low distortion, high feedback amps do not like to drive a real speaker. There are intersting measurement in the new Streoplay that scratch a bit on the surface.
You can have a look at the patent for more information. As I see it is not a differential circuit and needs a balanced drive.
Reinhard
Reinhard
I have an idea for a ballanced power buffer too. I wish i had more time for hobby.
I just got Michaels and my Paradise in good shape.
Thank you Alfred.
On one of my boards is no spider web. Should i install it ?
I just got Michaels and my Paradise in good shape.
Thank you Alfred.
On one of my boards is no spider web. Should i install it ?
The bulb-tester has 3 lamps, one for normal usage (in series with the ... under test) and the other two are used to discharge power supply buffer capacitors. Using clear bulbs give good visual feedback.
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Hi Joachim, you are welcome.
In fact all 4 boards oscillate pretty much the same way. If you can fix it without the spider, even better!
Please note all regulators work OK, and so do the servos. One of the servos is "pumping" but thats not the servo, that is the strong oscillation that causes a changing duty cycle at the output, and the servo is hopelessly trying to fix the DC component but can't....
its a very different beast trying to put real highspeed circuits into "production".....
Tell me about it.... even when not working there is so much stuff that fills the day...
BTW, I did follow through on one of your earlier ideas, using a OPA804 to drive a power MOSFET in source follower configuration as a power amplifier. In my case I use a power resistor between source and negative supply. And I designed the circuit so that the opamp is a difference amplifier, and I use two of these power amplifiers so I can have a true balanced input.
the build is almost ready... hope I can finish it over the weekend....
PS: the power resistor from output to negative supply is not shown in the schematic, but is a 10Ohm 50W resistor.
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That looks very interesting. Frans is also working on a power amp. If i had more time we could open a power amp thread,
Alfred, Michael thinks its the buffer. One simple fix i will try first is to bootstrap the output stage with a 150pF cap.
Well
My first english teacher told us to say "well".
So I do.
Have we seen one or two power amp threads somewhere?
I am not sure.
My first english teacher told us to say "well".
So I do.
Have we seen one or two power amp threads somewhere?
I am not sure.
If so, I will join,
have a little bit of experience in this direction -
in my words: "from top of the scrap bin".
