Douglas,
Yes, some old vintage amplifiers simply used the chassis as a universal ground path, rather than run connections on a ground bus, tied to chassis at a single point. (I assume it was a cheaper manufacturing build that way) My point being that it sounds OK - despite multiple good design practice violations - might be something to write about. Others have reported similar perceptions with such technically sub-par equipment. How is that possible?
Yes, I am thinking power amplifiers, but Analog, yet interfaced directly to a computer via a USB DAC. The small signal part would begin at the audio DAC outputs, in turn driving more small signal circuitry that eventually drives the power output devices. There may be more to it than simply connecting half A (the DAC) to half B (The Amplifier) that's worthy of consideration. Particularly if the DAC has 4 or more outputs, each with DSP capabilities.
Yes, some old vintage amplifiers simply used the chassis as a universal ground path, rather than run connections on a ground bus, tied to chassis at a single point. (I assume it was a cheaper manufacturing build that way) My point being that it sounds OK - despite multiple good design practice violations - might be something to write about. Others have reported similar perceptions with such technically sub-par equipment. How is that possible?
Yes, I am thinking power amplifiers, but Analog, yet interfaced directly to a computer via a USB DAC. The small signal part would begin at the audio DAC outputs, in turn driving more small signal circuitry that eventually drives the power output devices. There may be more to it than simply connecting half A (the DAC) to half B (The Amplifier) that's worthy of consideration. Particularly if the DAC has 4 or more outputs, each with DSP capabilities.
OPA1678 / OPA1679 is an important newcomer!
possibly other goodies from TI at different pricepoints, OPA164x / OPA165x might be interesting
NJM8068
...
🙂
The OPA1656 (open loop gain 150dB, lower THD) is said to be better than the LM4562. But I can't check that out yet.
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I believe the guitar pre section might be popular, there are a lot of players on this site, but not many threads. A section I would like to see is on compressors, (not just for guitars) IMHO one of the hardest analogue devices to design properly, and not much info on the web. I know its a device that isnt that common these days (digital devices are usually better, but you wont find them in many guit pres or pedals) and could fill a chapter in your book ( so many types) so i dont know if its worth it for you but this info is rare so it might sell some books.
Prelude: With all due respect to Kevin, I agree.
Having a "this was a bit hissy" moment?
all about.
Hi, my name is Sync, and I find it difficult to wade through all those
Hissy and Sissy words these guy who cant design write.
Heck, it turns out they can't write worth a chit, either.
Avoid unnecessary “fancy” words; use straightforward words
Other examples:
Educators love to say SYNTHESIZE this or that.
THE realist: Folks, we've gotta MAKE a snow flake today.
Kevin, you don't have that problem though. You write the difficult way.
That it, the most difficult things to write are simple, straightforward,
and clear, that is easy to understand. To take something complex and make it simple.
THAT is the Art of Writing.
Cheers,
Having a "this was a bit hissy" moment?
Come on kevin, just say it, that is what STEM write prose is
all about.
Hi, my name is Sync, and I find it difficult to wade through all those
Hissy and Sissy words these guy who cant design write.
Heck, it turns out they can't write worth a chit, either.
Avoid unnecessary “fancy” words; use straightforward words
Other examples:
Educators love to say SYNTHESIZE this or that.
THE realist: Folks, we've gotta MAKE a snow flake today.
Kevin, you don't have that problem though. You write the difficult way.
That it, the most difficult things to write are simple, straightforward,
and clear, that is easy to understand. To take something complex and make it simple.
THAT is the Art of Writing.
Cheers,
Holy Smoke PRR,
I've reached a new level of nausea with that one.
and "visual timbre" too boot!
That is some pretty exciting stuff. It's short, it's sweet, you can burn through
it quickly.
Image the sheer excitement of pounding out and maintaining 1500 page books of telecom switch documentation. It teaches you how to become numb and dumb.
I tried to demand my manager give me something better to work on,
like marketing communication (MAR-COM) flyers, reference guides, etc.
"Those are what we give to the contractors", mgr said.
"And I get punnished for being an employee! said Aye.
Guess who became contractor?
PRR - if only you had written with an essence of au-de-fumar
Cheers,
That wasn't so bad Bonsai,
but I think these might be the most obvious,
sadly our "reviewer" missed them.
Cheers,
Attachments
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Same here.
It would also be nice if there was a reliable source for PCBs for the designs presented in the book. The 2nd edition references the Signal Transfer company, though they seem to be out of business, or at the very least extremely challenging to order from - as discussed in The Signal Transfer Company thread.
It would also be nice if there was a reliable source for PCBs for the designs presented in the book. The 2nd edition references the Signal Transfer company, though they seem to be out of business, or at the very least extremely challenging to order from - as discussed in The Signal Transfer Company thread.
What designs? not that I have the latest book versions.
If these people running "Signal Transfer company" were on the up and up, they should announce their op status instead of keeping people in the dark. Not sure why someone would be paying for a web site/host with no intentions of doing any business with it, seems odd to me.
I'm making an assumption here. In his previous books, some of the content had a realized product available for purchase from the Signal Transfer Company as either bare PCBs or kits.
The small signal stuff is mainly fragments of mixing desk, not so easy to package as a power amplifier. Some of the preamps or gain/tone controls would be amenable as self-contained projects, as would some of the power supply stuff I think.
I think pulling those 'fragments of a mixing desk' together as channel strips would be an interesting project.
I just discovered this thread and meanwhile the 3rd edition is about to be released.
Some years ago I bought the 2nd edition of Small Signal Audio Design to understand how RIAA equalisation is implemented and hopefully to find out how it could be modified into NAB or CCIR equalisation for tape head pre-amps.
As mentioned earlier there's a serious open reel tape deck revival and prices of used reel-to-reel decks have multiplied over the last decade.
Also some new decks are on the market (Ballfinger, Thorens, in near future also Metaxas) but only for extreme prices. So the tape enthousiasts are limited to the open reel tape decks mostly produced in the 70 and 80's.
Outboard tape head preamps for playback only are available, but again high prices.
As a hobby I refurbish some open reel deck models (Pioneer, Technics, Revox) but I'm sure there's room for improvement in the used tape head replay and record amplifiers.
I was delighted to read in this thread a chapter would be dedicated to tape replay in the 3rd edition.
However, going through the TOC (preview Amazon) the Tape Replay Amplifiers are only covering 2 pages in the book, so not sure if it's worth for me to purchase the 3rd edition for this reason only.
Will a practical tape replay amp be presented? With op-amp's or discrete transistor circuitry?
Some years ago I bought the 2nd edition of Small Signal Audio Design to understand how RIAA equalisation is implemented and hopefully to find out how it could be modified into NAB or CCIR equalisation for tape head pre-amps.
As mentioned earlier there's a serious open reel tape deck revival and prices of used reel-to-reel decks have multiplied over the last decade.
Also some new decks are on the market (Ballfinger, Thorens, in near future also Metaxas) but only for extreme prices. So the tape enthousiasts are limited to the open reel tape decks mostly produced in the 70 and 80's.
Outboard tape head preamps for playback only are available, but again high prices.
As a hobby I refurbish some open reel deck models (Pioneer, Technics, Revox) but I'm sure there's room for improvement in the used tape head replay and record amplifiers.
I was delighted to read in this thread a chapter would be dedicated to tape replay in the 3rd edition.
However, going through the TOC (preview Amazon) the Tape Replay Amplifiers are only covering 2 pages in the book, so not sure if it's worth for me to purchase the 3rd edition for this reason only.
Will a practical tape replay amp be presented? With op-amp's or discrete transistor circuitry?
I have recently run some tests on the NJM8068.
Unimpressive and no substitute for the 5532/4.
BTW, I assume some of you have the book by now, despite all the dislocation.
I would be happy to hear what you think of it.
There are strong indications that the new OPA1656 should have even less distortion than the LM4562. Further more in-depth tests would be worthwhile here.
That OPA1656 looks really promising. Not stupidly expensive. Nice datasheet too. Thanks for mentioning it.
The OPA1656 came out best for the autoranger update. Very good all-round opamp unless you need the very lowest noise.
Not available in DIL case though, which is no problem for me.
Jan
Not available in DIL case though, which is no problem for me.
Jan