Anonanimal
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^----- Hahaha!
A nice(?), simple chip amplifier
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cobaltmute
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Quote:
totally off topic for the thread (and apologies for that), but what do you use to draw these schematics?
Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif 
|
totally off topic for the thread (and apologies for that), but what do you use to draw these schematics?
nattonrice
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They do look like something from the 40's =P
Steve Eddy
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Well, I first started creating the symbols in AutoCAD some 20 years ago or so, and then some years later ported them into a vector graphics program similar to CorelDRAW called Xara (and at the time I bought it many years ago, Xara was owned by Corel).
I still use the same process and programs today.
se
| Originally Posted by cobaltmute /img/forum/go_quote.gif totally off topic for the thread (and apologies for that), but what do you use to draw these schematics? |
Well, I first started creating the symbols in AutoCAD some 20 years ago or so, and then some years later ported them into a vector graphics program similar to CorelDRAW called Xara (and at the time I bought it many years ago, Xara was owned by Corel).
I still use the same process and programs today.
se
Steve Eddy
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Being something of an anachronist, I was influenced by schematic drawings from the 30's and 40's when I created the symbols that I use.
se
| Originally Posted by nattonrice /img/forum/go_quote.gif They do look like something from the 40's =P |
Being something of an anachronist, I was influenced by schematic drawings from the 30's and 40's when I created the symbols that I use.
se
IPodPJ
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Is that really your father?
Steve Eddy
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Naah. Just me being a smartass.
se
| Originally Posted by IPodPJ /img/forum/go_quote.gif Is that really your father?
|
Naah. Just me being a smartass.
se
cobaltmute
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Quote:
That explains why they look like art. I do like the look.
| Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Well, I first started creating the symbols in AutoCAD some 20 years ago or so, and then some years later ported them into a vector graphics program similar to CorelDRAW called Xara (and at the time I bought it many years ago, Xara was owned by Corel). I still use the same process and programs today. se |
That explains why they look like art. I do like the look.
00940
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Quote:
Open loop diamond buffer (that's what the BUF634 is) ? You'll have to deal with DC offset.
| Originally Posted by Koyaan I. Sqatsi /img/forum/go_quote.gif Holly came from Miami, F.L.A. Hitch-hiked her way across the USA Plucked her eyebrows on the way Shaved her legs and then he was a she She says, Hey babe Take a walk on the wild side Hey honey Take a walk on the wild side 
se |
Open loop diamond buffer (that's what the BUF634 is) ? You'll have to deal with DC offset.
diditmyself
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With OPA627 you can't go (much) wrong. This could be a fine sounding amp.
Some suggestions:
1. I think the gain is far to high. You'll have problem adjusting the volume and the amp will be noisy.
2. If your source doesn't have DC on it's output (it's probably already capacitor coupled) you dont need the C1 cap. I think an input resistor will do more good.
3. If you're using a 50k pot, the R1 resistor should be something like 470k to 1M.
4. A resistor between opamp and buffer might increase the stability. Use something like 47R to 100R.
5. How the return currents are handled is as important as L/R channels. 3-channel topology, IC-regulators, large and good capacitors - the choice is yours, but make it good. I know what I like but I'm not going to start a war in this thread.
6. Why not use a PIMETA v2 board? Room for fancy capacitors? With a DC-coupled 3 ch amp, who cares about capacitors!
Some suggestions:
1. I think the gain is far to high. You'll have problem adjusting the volume and the amp will be noisy.
2. If your source doesn't have DC on it's output (it's probably already capacitor coupled) you dont need the C1 cap. I think an input resistor will do more good.
3. If you're using a 50k pot, the R1 resistor should be something like 470k to 1M.
4. A resistor between opamp and buffer might increase the stability. Use something like 47R to 100R.
5. How the return currents are handled is as important as L/R channels. 3-channel topology, IC-regulators, large and good capacitors - the choice is yours, but make it good. I know what I like but I'm not going to start a war in this thread.
6. Why not use a PIMETA v2 board? Room for fancy capacitors? With a DC-coupled 3 ch amp, who cares about capacitors!
Steve Eddy
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Thanks.
se
| Originally Posted by cobaltmute /img/forum/go_quote.gif That explains why they look like art. I do like the look. |
Thanks.
se
Steve Eddy
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Quote:
True enough. It was a bit too flippant of me to tack on the BUF-634 label like that. I was only intending to get the basic idea across rather than produce a buildable schematic.
I've edited the image to make it more generic.
se
| Originally Posted by 00940 /img/forum/go_quote.gif Open loop diamond buffer (that's what the BUF634 is) ? You'll have to deal with DC offset. |
True enough. It was a bit too flippant of me to tack on the BUF-634 label like that. I was only intending to get the basic idea across rather than produce a buildable schematic.
I've edited the image to make it more generic.
se
diditmyself
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Quote:
No problems. Just add a resistor or CCS to the input to balance the bias currents.
| Originally Posted by 00940 /img/forum/go_quote.gif Open loop diamond buffer (that's what the BUF634 is) ? You'll have to deal with DC offset. |
No problems. Just add a resistor or CCS to the input to balance the bias currents.
PJPro
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Quote:
Yeah, I know where you're coming from. I'd prefer a bit more space sometimes.
| Originally Posted by Slash47 /img/forum/go_quote.gif .......I personally don't like the lack of space on some ready made PCB's..... |
Yeah, I know where you're coming from. I'd prefer a bit more space sometimes.
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