Hi all,
I appreciate your responce and I thank you for the ideas you shared... Its enough for me to start to do researching.
Thanks again,
joe
|
Hi all,
I appreciate your responce and I thank you for the ideas you shared... Its enough for me to start to do researching.
Thanks again,
joe
|
Throw a few things together on a piece of vero board, couple of lines of code in a 16f628 (my favorite pic), hookup a source input and give your ears a whirl. Worst that can happen is it doesn't work as good expected, dust yourself off and try again
|
Hmm, it has higher THD and is controlled by analog voltage. So a DAC is really needed. More noise source and more difficult PCB. I can assure you Steve, it is a HI-FI device. I am high fidelist myself too.Originally Posted by mister_e
Very nice indeed! This is what can be called art!
Yes, but I suppose that is a dominant rule in almost all electronics designs though. Good ground, capacitors on power lines, and seperatew analog and digital voltage sources to name a few. The vero board I can guess will not give optimum results in this case. It is not a LED test circuit...
Ioannis
|
I think star point earthing is pretty much industry standard for quality audio circuitry. Best way to avoid the dreaded earth loop.
|
Never mind Art - that's Engineering... I actually spent about ten minutes admiring that design... it is so way ahead of it's time it's almost uncanny...
It's not multi-channel audio, but just consider... Centre Bass Speaker (today we'll have a Centre Bass and we call it a Woofer), Centre High Range (today we have centre tweeters), Left & Right Mid-Range... all the elements of what today is 'Home Cinema'.
Motorised Turret Tuner - that's about five years ahead from when MANUAL one's were introduced into TV sets... never seen a Turret Tuner in a plain radio receiver from a western manufacturer... let alone a motorised one!
Cable Remote... Volume, Tuning and Wavechange and even Dial-Lights (how many Remotes do you have in your house with integral illumination?)... and look how THIN the cable to the Remote is... OK, it is done by wire (ie mechanical), but that's not the point.
B7G & B9A valves - when in the West most manufacturers were still fitting Octal...
The more you look at it, the more innovation you find... this is World-beating leading-edge technology of it's day - and for a domestic consumer market... it's a shame, so few people will look at that and realise what's actually there... just another square wooden box with valves inside...
|
It looks like the people assembling that great radio, really liked what they were doing!
Imagine to have a production of this thing made by bare hands!
|
My two cents.
I wish I had seen this thread earlier as I would have given a thumbs up for the PGA2320 Volume control chip from TI. I have one of them running my Gainclone amp and couldn't be happier with it although I don't consider myself an Audiophile by any means.
I control it with 3 pushbuttons, increase gain, decrease gain and a third for Mute, all running from a 16f876.
Here are a few pictures.
The first is the PGA in action. The thing to the left is a programming dongle I use to cram stuff into the bootloader and the heavy white wire goes to a LM34 to take the temperature of the Amp chip.
The second is of the amp itself, a dual mono.
The third is a 7 segment display I'm toying with to show gain.
|
Not getting into the advisability of using (or not) a semiconductor for controlling the volume, my vote goes to the DS1869 http://www.maxim-ic.com/appnotes.cfm/an_pk/168
Its perhaps the simplest a digital volume control can get and has been working flawlessly for a couple of years in one of my apps.
Regards,
Anand
Members who have read this thread : 1You do not have permission to view the list of names.
Posting Permissions
Bookmarks