Salas
Here a picture of my actual power amps:
The mid horns and the tweeter are protected against DC with the big black caps, bypassed by sovjet caps.
One of those big caps is more expensive than one of the stereo t-amp boards...
Franz
Here a picture of my actual power amps:
An externally hosted image should be here but it was not working when we last tested it.
The mid horns and the tweeter are protected against DC with the big black caps, bypassed by sovjet caps.
One of those big caps is more expensive than one of the stereo t-amp boards...
Franz
Unfortunately good coupling capacitors are a layout and pocket killer. So I try to be inventive by carefully mixing what I have in my hobby box right now. Did many auditions against DC coupling to use that mix. I hope it will co work decently on that new phono board in the end. Has enough work to be done underneath the perf board still. Near finishing your reg?
Not yet.
Next, I will make two stripeboards with a delay circuit, based on NE555, to get rid of the power up and down problem of the crossover by grounding the outputs of the active crossover.
Then, I can proceed safely to the shunt regulator.
And dont forget: I had to measure and adjust the levels and phases of my active crossover in the last two days.
Franz
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You watch football and blow vuvuzelas, I experiment on phono.
Nice & neat master work as expected
What kind of output caps are you using?
Are you bypassing polipropylene ouput caps with teflon caps?
All RIAA caps are russians teflon not silver mica....T-1 15nF instead 16nF, 47nF are russians & real value is 47nF, I can't see russian model?
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About output caps I don't know the maker. They are pull outs from a Chinese kit, they just have ''MPP'' on them. They happened to mix nicely with FT-1 bypass in my preliminary experiments on a DCB1's doubled output for DC VS Capacitors comparisons. In the RIAA I use ceramic C0G/NP0 as I wrote. They proved very decent subjectively and save layout size. Teflon is superior, I have compared, and it would be best if someone uses Teflon for Riaa filter too. This CCT has different values, lower impedance filter, so I got 30 33nF 50V 10% C0Gs and found exact values via paralleling. Its an experimental board, has many tweaks. Another problem for using expensive caps for the filter is having enough for reaching exact and matched values.
They are pull outs from a Chinese kit, they just have ''MPP'' on them. They happened to mix nicely with FT-1 bypass in my preliminary experiments on a DCB1's doubled output for DC VS Capacitors comparisons. In the RIAA I use ceramic C0G/NP0 as I wrote. They proved very decent subjectively and save layout size. Teflon is superior, I have compared, and it would be best if someone uses Teflon for Riaa filter too. This CCT has different values, lower impedance filter, so I got 30 33nF 50V 10% C0Gs and found exact values via paralleling. Its an experimental board, has many tweaks. Another problem for using expensive caps for the filter is having enough for reaching exact and matched values.
I use 9.5mA cascoded quads then 8.5mA 2nd stage then 7.6mA buffer with source CCS like B1. If it will pull as expected it may go 61.5dB. Don't know yet. Needs copper side wiring work, measurements, enclosure, and its 40C these days. I am experimenting on less noise possible and I hope that the high current 1.1k impedance first stage will prove gutsy enough to drive the 22K filter and charge up its 100nF caps with decent slew rate. Its a Guinea pig right now.
No worries, I do it all the time.
It will either do something better or it will wimp out on the lower impedance and sound like a tacky plastic vuvuzela.
Necessarily so. Its experimental and I don't know its best bias, since it will affect the buffer too. I have trimmers for the first stage in the back pocket also, if it will pull differently enough between channels. As for vuvuzela.... Mount a couple to waveguide your tweeters If you want your HF to give you err.. a buzz that is.
Mount a couple to waveguide your tweeters If you want your HF to give you err.. a buzz that is.
Spooky
I guess there might be someone that can pull real tunes out of the thing.
I used to see those on top of the big trucks (metal crome ones).
PS: I am not really into football so sometimes I do not grasp the funny parts imediately.
I am looking forward to read your comments about those ceramic caps.
As for the teflon bypasses, what are the values ?
I guess there might be someone that can pull real tunes out of the thing.
I used to see those on top of the big trucks (metal crome ones).
PS: I am not really into football so sometimes I do not grasp the funny parts imediately.
I am looking forward to read your comments about those ceramic caps.
As for the teflon bypasses, what are the values ?
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Spooky
I guess there might be someone that can pull real tunes out of the thing.
There is always hope, well it takes some practice from the guy to the left to reach the guy to the right, but loving it is all it takes.
Attachments
http://www.diyaudio.com/forums/parts/168423-c0g-np0-coupling-caps.html
The FT-1 Teflon are 22nF each.
There is always hope, well it takes some practice from the guy to the left to reach the guy to the right, but loving it is all it takes.
No hope
, needs more than some practice to play like the master Miles Davis