Rick: I guess I'm ready. Although I'd like to get a E1DA Cosmos ADC for testing. My Old HP3580A Spectrum Analyzer is a bit long in the tooth.
This will take some months I would estimate.
This will take some months I would estimate.
Bob uses his distortion magnifier with his SA
Another project for me
We been at it for a few years now so take your time
Another project for me
We been at it for a few years now so take your time
Not sure if you're still looking for someone to try things out?
I have all the parts listed in the book - not connectors etc.
Else would be happy to pay for untested prototype boards!
Let me know. Many thanks
Simon
I have all the parts listed in the book - not connectors etc.
Else would be happy to pay for untested prototype boards!
Let me know. Many thanks
Simon
Machining is done, PCBs are mostly assembled (small signal BJT only items left). Chassis wiring is next, then testing. PCBs are very nice.
Good to hear your are progressing along.
You were asking about TMC comp so I asked Bob,
The answer to the TMC question is historical irony. The BC-1 as described in my second edition was intended as a fairly simple introductory amplifier design with not too many bells and whistles. I had no idea it would end up performing so well. I think I did experiment with TMC on it at one point quite awhile back. Its not difficult to fit it with TMC - one just splits the Miller capacitor and hangs the junction in mid-air, then connects the junction through a resistor to the output ahead of the coil. I don't recall what the values were. I had also used it as a test bench for fooling around with the DoubleCross output stage.
I have since run some simulations with TMC on the BC-1 design. I referenced the paper on TMC/TPC in Linear Audio v6. I will also run some tests.
You were asking about TMC comp so I asked Bob,
The answer to the TMC question is historical irony. The BC-1 as described in my second edition was intended as a fairly simple introductory amplifier design with not too many bells and whistles. I had no idea it would end up performing so well. I think I did experiment with TMC on it at one point quite awhile back. Its not difficult to fit it with TMC - one just splits the Miller capacitor and hangs the junction in mid-air, then connects the junction through a resistor to the output ahead of the coil. I don't recall what the values were. I had also used it as a test bench for fooling around with the DoubleCross output stage.
I have since run some simulations with TMC on the BC-1 design. I referenced the paper on TMC/TPC in Linear Audio v6. I will also run some tests.
Alas, the circuit for BC-1 doesn't appear to be in my 2011 1st edition 😢
Would it be OK to post a pic of the schematic?
Would it be OK to post a pic of the schematic?
Bob Cordell made a BC-1 presentation at a 2019 burning amp event that is available on YouTube, it has the schematic
If you search YouTube for BobCordell it shows up.
If you search YouTube for BobCordell it shows up.
Well we are finally there with a few builds complete and a few BC-1 still being built and beta tested by two members that have taken on the challenge. They been given a set of pcbs to build and review the documentation.
It’s been a while I have forgotten but we will eventually make the design available. I won’t be giving out the fab data but we can make arrangements offline if you like to take it on. I’ll have to order more pcbs since I am all out of the first batch.
It’s been a while I have forgotten but we will eventually make the design available. I won’t be giving out the fab data but we can make arrangements offline if you like to take it on. I’ll have to order more pcbs since I am all out of the first batch.
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Looks good Zoji6645, worth all the effort and $?
I run my tuner straight into the BC-1 amp, it has a volume control.
No, I mean why the BC1 is divided into 2 pcbs.
https://www.diyaudio.com/community/attachments/bc-1-assembled-pcbs-2-jpg.1086035/
https://www.diyaudio.com/community/attachments/bc-1-assembled-pcbs-2-jpg.1086035/
