digital volume control

aardvarkash10 · 8th December 2008, 07:34 AM

anyone implimented a digital (or other SS) volume control in their tube amplification? I'm thinking it would provide a relatively simple and clean faceplate solution and easily interface with remote control. Especially like the look of the IC based solutions eg Maxim or similar. Comments please.

analog_sa · 8th December 2008, 08:41 AM

DS1666 with push buttons. About to do it with a rotary encoder.

Not as bad as i anticipated. Better than cheap pots and at least no opamps inside. Should be easy to integrate a remote. And ARC uses it in their REF preamps.

kuroguy · 8th December 2008, 12:02 PM

6 relays, 12 resistors, one uln2001 and a microcontroller. gives 64 steps and I've picked the resistors for 1 db steps. Could easily change the attenuation per step and increase to 128 or even 256 steps if I wanted. Microcontroller is a BasicX24, but could be a pic instead. gonna use buttons for vol up and down, but could easily use a linear variable resistor connected to the microcontroller ADC to adjust volume too.

SRMcGee · 8th December 2008, 12:10 PM

aardvarkash10:

Do you mean like this? This is an Aikido preamplifier (preamp on the left, power supply on the right) with a Dantimax remote control system.

Regards,
Scott

aardvarkash10 · 8th December 2008, 06:59 PM

very nice solution scott - sorta raises the bar on my expectations! Yeah, I aslo considered relays and resistor networks, but it seems a lot of additional effort and a big opportunity for Mr StuffUp to enter the picture. Maybe at a later date! Thanks for the DS1666 solution - looks like the sort of thing I was after. Cheers all.

gingertube · 9th December 2008, 01:57 AM

I get the Dallas / Maxim Engineering Journal and Design Guides sent to me in my day job.

3 more to look at (their descriptive prose, my comments):

#1
"Simplest Pushbutton Interface Controls Audio Volume and Balance" - MAX5457
My notes:
2 independent 10K Ohm potentiometers, will need buffer to drive that impedance
32 tap audio taper, steps of 2dB
UP, DOWN, MODE, MUTE(-90dB) Push Buttons
MODE toggles between Balance and Volume, there is a LED driver to indicate the mode.
Shutdown pin (active low) - stores last wiper position.
Same thing with separate Volume and Balance Up Down switches is MAX5456

#2
"Push Button Audio-Control IC Mixes Two Independent Stereo Sources" - MAX5406
My notes:
VOL UP/Down Switches
BALANCE L/R Switches
BASS UP/DOWN Switches (external Cap to set operating freq)
TREBLE UP/DOWN Switches (external Cap to set as above)
"AMBIENCE" Switch (artificially "enhances" stereo separation)
MUTE Switch
50K Input Impedance
32 step audio taper, 2dB per step
Pseudo Stero for Mono Sources
Sub Woofer Output
Shutdown store last Wiper Settings.

#3
"Rotary Encoder IC Controls Volume and Balance without uC" - MAX5440
My notes:
Integrated low power <0.003% THD Buffers
5 segment LED Setting Indicator shows Volume or Balance
-12dB Power on Reset
32 Tap Audio Taper
-90dB Mute.

Cheers,
Ian

analog_sa · 9th December 2008, 05:56 AM

Surprising suggestions Gingertube: all seriously lo fi.

Koifarm · 9th December 2008, 01:41 PM

A lot of people use the one i link below, myself included.

For Share: Remote Volume Control KIT

Boris_The_Blade · 9th December 2008, 02:59 PM

http://www.profusionplc.com/pro/gex/...rtno=MAS6116AA

A copy of the (discontinued) Wolfson WM8816.

peterr · 10th December 2008, 10:05 AM

Guido Tent sells THIS

8th December 2008, 06:59 PM	#5
aardvarkash10 diyAudio Member Join Date: Mar 2007 Location: Auckland, NZ	thanks guys very nice solution scott - sorta raises the bar on my expectations! Yeah, I aslo considered relays and resistor networks, but it seems a lot of additional effort and a big opportunity for Mr StuffUp to enter the picture. Maybe at a later date! Thanks for the DS1666 solution - looks like the sort of thing I was after. Cheers all. __________________ Yes, conservatism thrives on low intelligence and poor information. But the liberals in politics... continue to back off, yielding to the supremacy of the stupid. It's turkeys all the way down. - George Monbiot, guardian.co.uk, 6 Feb 2012

10th December 2008, 10:05 AM	#10
peterr diyAudio Member Join Date: Apr 2002 Location: Amsterdam	Guido Tent sells THIS __________________ Keep an open mind. It helps. Peter

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: Advanced Search

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Digital Volume Control	soundNERD	Chip Amps	17	3rd June 2011 08:00 PM
Digital volume control	day1118	Digital Line Level	8	21st November 2008 08:11 PM
Digital volume control	maharadza	Digital Source	9	8th April 2006 04:59 PM
Which VCA for Digital volume control	gmphadte	Analogue Source	8	30th September 2004 11:21 AM
Digital Volume control for in Car use	dunderchief	Digital Source	7	28th March 2004 12:08 AM

New To Site?	Need Help?
Register to Participate Search Privacy Statement Contact Us	Frequently Asked Questions Did you forget your password? Mark Forums Read

8th December 2008, 07:34 AM	#1
aardvarkash10 diyAudio Member Join Date: Mar 2007 Location: Auckland, NZ	digital volume control anyone implimented a digital (or other SS) volume control in their tube amplification? I'm thinking it would provide a relatively simple and clean faceplate solution and easily interface with remote control. Especially like the look of the IC based solutions eg Maxim or similar. Comments please. __________________ Yes, conservatism thrives on low intelligence and poor information. But the liberals in politics... continue to back off, yielding to the supremacy of the stupid. It's turkeys all the way down. - George Monbiot, guardian.co.uk, 6 Feb 2012

8th December 2008, 08:41 AM	#2
analog_sa diyAudio Member Join Date: Aug 2002 Location: Sofia	DS1666 with push buttons. About to do it with a rotary encoder. Not as bad as i anticipated. Better than cheap pots and at least no opamps inside. Should be easy to integrate a remote. And ARC uses it in their REF preamps.

8th December 2008, 12:02 PM	#3
kuroguy diyAudio Member Join Date: Sep 2007	6 relays, 12 resistors, one uln2001 and a microcontroller. gives 64 steps and I've picked the resistors for 1 db steps. Could easily change the attenuation per step and increase to 128 or even 256 steps if I wanted. Microcontroller is a BasicX24, but could be a pic instead. gonna use buttons for vol up and down, but could easily use a linear variable resistor connected to the microcontroller ADC to adjust volume too.

9th December 2008, 01:57 AM	#6
gingertube diyAudio Member Join Date: Oct 2004 Location: Adelaide South Oz	I get the Dallas / Maxim Engineering Journal and Design Guides sent to me in my day job. 3 more to look at (their descriptive prose, my comments): #1 "Simplest Pushbutton Interface Controls Audio Volume and Balance" - MAX5457 My notes: 2 independent 10K Ohm potentiometers, will need buffer to drive that impedance 32 tap audio taper, steps of 2dB UP, DOWN, MODE, MUTE(-90dB) Push Buttons MODE toggles between Balance and Volume, there is a LED driver to indicate the mode. Shutdown pin (active low) - stores last wiper position. Same thing with separate Volume and Balance Up Down switches is MAX5456 #2 "Push Button Audio-Control IC Mixes Two Independent Stereo Sources" - MAX5406 My notes: VOL UP/Down Switches BALANCE L/R Switches BASS UP/DOWN Switches (external Cap to set operating freq) TREBLE UP/DOWN Switches (external Cap to set as above) "AMBIENCE" Switch (artificially "enhances" stereo separation) MUTE Switch 50K Input Impedance 32 step audio taper, 2dB per step Pseudo Stero for Mono Sources Sub Woofer Output Shutdown store last Wiper Settings. #3 "Rotary Encoder IC Controls Volume and Balance without uC" - MAX5440 My notes: Integrated low power <0.003% THD Buffers 5 segment LED Setting Indicator shows Volume or Balance -12dB Power on Reset 32 Tap Audio Taper -90dB Mute. Cheers, Ian

9th December 2008, 05:56 AM	#7
analog_sa diyAudio Member Join Date: Aug 2002 Location: Sofia	Surprising suggestions Gingertube: all seriously lo fi.

9th December 2008, 01:41 PM	#8
Koifarm diyAudio Member Join Date: Aug 2005	A lot of people use the one i link below, myself included. For Share: Remote Volume Control KIT

9th December 2008, 02:59 PM	#9
Boris_The_Blade diyAudio Member Join Date: Mar 2007	http://www.profusionplc.com/pro/gex/...rtno=MAS6116AA A copy of the (discontinued) Wolfson WM8816.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)