R2R Shunt Volume with 3 selectable sources

[quanghao]

This design:

http://www.audiodesignguide.com/VolumeNew/index.html

HQ-R/2R VOLUME Technical Specifications:
Specifications:
– low tolerance 0.1% R-2R network with melf resistors ( resistors in parallel produce a pure resistor).
– attenuation in 64 steps - each step 1dB
– Input resistance ranges from 20k to 47K for a Rload of 47K.
– Output resistance ranges from 22K to 47K.
– 3 selectable inputs with option to edit input name
– one direct input
– display back-light programmable On/Off - if Off timeout 10s
- 20X 4 display characters for wide view
– tube menu for delaying plate voltage
- 3-modules design: Powers Supply (PS), Control and Display Unit (CDU), Relay Module (RM) in SE or Balanced modification.
-Volume attenuation by rotating optical encoder or from IR remote control.
- Input selection by rotating optical encoder or from IR remote control
- Display auto dimming with adjustable brightness level
- ONE open collector outputs for power On/Off and tube plate delay
- Main AC power on/off control
– AC power consumption, Max. 6W.


Special : The avoidance of clicks is the major improvement with respect to my original attenuator design of several years back.

in most of the design volume -32db relay at transition to -31dB, the relay volume 64 steps are emitting huge sound in the speakers, causing discomfort, not safe for the system.

I definitely settle this phenomenon, therefore, very smooth transition Volume and sound great.

This link for Video of Volume: https://www.youtube.com/watch?v=s9QEZduZavs

this complete module assembled including the aluminium remote at 250$ + shipping.

thanks


please see some other designs:

The δ1 relay-based R-2R stereo attenuator

Audio Volume Relay Attenuator with IR Control

VC-03 Volume Control

[Junie]

This seems to be a good option for my GM preamp clone, what is the size of the LCD display? I have a Chassis but I want to know if the display will fit on the front panel.

[quanghao]

Hi Junie!

this for make it!

thanks

[sumotan]

Hi Quanhao

wrote to you about this item but did not get any response from you

[quanghao]

Hi Jaffrie!

what i can help you now ?

thanks your advice!
quanghao

[sumotan]

Hi
1. Understand that there's a power on delay build inn. What is the time frame & is this adjustable ?

2. Possible to link the power on to power amp as well ?

3. What is the actuall price of the complete unit as I see $200 n $ 250

Thks

[quanghao]

Hi Jaffrie!

1. Understand that there's a power on delay build inn. What is the time frame & is this adjustable ?

The delay turn on for amplifier about 5s

The delay for the output about 10s

2. Possible to link the power on to power amp as well ?

yes, can use for your amplifier , but the relay on about 5A to 8A ( you can use other relay if your amplifier need big current )

3. What is the actuall price of the complete unit as I see $200 n $ 250

Price 250$ + shipping!
thanks

quanghao

[sumotan]

Thanks for the reply. Can the delay to programme for long power on time ?
Building an hybrid amp so need tube stage to be dc free before Ss amp stage powers on.

Also whats your paypal account

Thks

[sumotan]

Hey Quanghao

Awaiting for your reply. Wanted to order this item but in your webshop I only see an remote
listed at 199.99 is this the item ?

[RollE2k]

How does the balanced input board look?