I am looking arround to RC volume control kits, at best include envelope (enclosure) and RC transmitter hand set unit (motor pot or dig. controlled). Please note: Not digital attenuator, but digital controlled attenuator.
On ebay there are a wide range of bidders without envelope and only partly solutions (either only RC transmitter/receiver unit or only volume control unit with SPI controlled pins), but I want to have a completly kit like Vellemann K8022.
At follow this no longer available Vellemann Kit and some other examples:
A: RC Motor Analog-Potis
1) Velleman K8022 PASSIV Preamp with remote control
K8022 Passiver Vorverstärker mit RF-Fernbedienung im Sly-electronic Shop Berlin
http://www.sly.de/bbilder/k8022.jpg
Fernsteuersender Handsender 2 Kanal VM130T - Lüdeke Elekronic Elektronikhandel
http_www_velleman.eu/distributor/products/view/?id=345984
associated RC transmitter:
http_www_velleman.eu/distributor/products/view/?id=374092
2) RCLL, Remote Controlled Line Level Volume Control
Audioplex RCLL-1 Remote Controlled Line Level VC
http://www.audioplex.com/RCLL1 revised.pdf
3) MK161 - IR 2 Channel Remote Receiver Kit
MK161 - IR 2 Channel Remote Receiver Kit - Ramsey Electronics
4) MV-04 motorize remote volume control
DIYCLUB
5) Remote control audio kit
Dantimax - Remote control audio kits
B. Remote Controlled Switched Resistors by Relay
1) The remote control paratactic volume control
http://www.diyaudio.com/forums/solid-state/56009-remote-control-paratactic-volume-control.html
2) Audio Volume Relay Attenuator with IR Control
Audio Volume Relay Attenuator with IR Control
3) Remote volume control board, using relay - Halcro also use relay on their DA10 pre amp
DIYCLUB
4) VolControl, Volume/attenuator control board
Dantimax (elektronik) - Control_boards
5) TentLabs Volume control
Volume control
more kits:
DIYCLUB
C) Semiconductor switches (C-MOS series)
1) Remote Controlled Stepped Attenuator
Welborne Labs Remote Controlled Attenuator
2) RC-16 Remote Volume Control (looks like that one from Cyrus III and Cyrus IIIi / Cyrus 3i)
http://www.oxmoor.com/files/cut sheets/DCA-2 RC-16 cut sheet.pdf
RC-16 Remote Volume Control - Oxmoor Professional Audio Products
And here several IC solutions for volume control application:
Digital Potentiometer
Digital Potentiometers and Capacitors (ISL22317)
Digital Volume Control
Volume Control - Volume Controls (CS3318)
2-Channel 78 dB Audio Attenuator
LM1972 - Micro-Pot 2-Channel 78 dB Audio Attenuator with Mute
Stereo Audio Volume Control (PGA2310-2311-2320-4311)
Audio - Volume Control - PGA2310 - TI.com
Electronic Audio Attenuator dc controlled (MC3340)
http://www.datasheetcatalog.org/datasheet/motorola/MC3340.pdf
MAS9116 - Stereo Digital Volume Control
MAS9116 pdf, MAS9116 description, MAS9116 datasheets, MAS9116 view ::: ALLDATASHEET :::
Dual-Channel Digital Volume Control with CMOS switch 4066
http://www.electronicsforu.com/efylinux/circuit/feb2003/aug99_dualchannel.pdf
Digital controlled stereo audio processor TDA7313 (ST)
http://ampslab.com/PDF/tda7313.pdf
http://www.st.com/stonline/stappl/p...type=4&tname=TL_DATASHEET_TREE_X_DOC&latest=N
Maxim DS8102 - the new volume control chip
http://datasheets.maxim-ic.com/en/ds/DS1802.pdf
DS8102 Dual Delta-Sigma Modulator and Encoder - Overview
DIY: high end DAC and digital volume control | Flickr - Photo Sharing!
TDA7439 (Linn Kolektor) THREE BANDS DIGITALLY CONTROLLED AUDIO PROCESSOR (ST)
http://www.datasheetcatalog.org/datasheet/stmicroelectronics/4291.pdf
In the attachement various CMOS solution schematics.
I want to have a good overview about completly kits like the no longer available Vellemann K8022.
Thank you for additional proposals.
(copyrighted images removed by moderators)
On ebay there are a wide range of bidders without envelope and only partly solutions (either only RC transmitter/receiver unit or only volume control unit with SPI controlled pins), but I want to have a completly kit like Vellemann K8022.
At follow this no longer available Vellemann Kit and some other examples:
A: RC Motor Analog-Potis
1) Velleman K8022 PASSIV Preamp with remote control
K8022 Passiver Vorverstärker mit RF-Fernbedienung im Sly-electronic Shop Berlin
http://www.sly.de/bbilder/k8022.jpg
Fernsteuersender Handsender 2 Kanal VM130T - Lüdeke Elekronic Elektronikhandel
http_www_velleman.eu/distributor/products/view/?id=345984
associated RC transmitter:
http_www_velleman.eu/distributor/products/view/?id=374092
2) RCLL, Remote Controlled Line Level Volume Control
Audioplex RCLL-1 Remote Controlled Line Level VC
http://www.audioplex.com/RCLL1 revised.pdf
3) MK161 - IR 2 Channel Remote Receiver Kit
MK161 - IR 2 Channel Remote Receiver Kit - Ramsey Electronics
4) MV-04 motorize remote volume control
DIYCLUB
5) Remote control audio kit
Dantimax - Remote control audio kits
B. Remote Controlled Switched Resistors by Relay
1) The remote control paratactic volume control
http://www.diyaudio.com/forums/solid-state/56009-remote-control-paratactic-volume-control.html
2) Audio Volume Relay Attenuator with IR Control
Audio Volume Relay Attenuator with IR Control
3) Remote volume control board, using relay - Halcro also use relay on their DA10 pre amp
DIYCLUB
4) VolControl, Volume/attenuator control board
Dantimax (elektronik) - Control_boards
5) TentLabs Volume control
Volume control
more kits:
DIYCLUB
C) Semiconductor switches (C-MOS series)
1) Remote Controlled Stepped Attenuator
Welborne Labs Remote Controlled Attenuator
2) RC-16 Remote Volume Control (looks like that one from Cyrus III and Cyrus IIIi / Cyrus 3i)
http://www.oxmoor.com/files/cut sheets/DCA-2 RC-16 cut sheet.pdf
RC-16 Remote Volume Control - Oxmoor Professional Audio Products
And here several IC solutions for volume control application:
Digital Potentiometer
Digital Potentiometers and Capacitors (ISL22317)
Digital Volume Control
Volume Control - Volume Controls (CS3318)
2-Channel 78 dB Audio Attenuator
LM1972 - Micro-Pot 2-Channel 78 dB Audio Attenuator with Mute
Stereo Audio Volume Control (PGA2310-2311-2320-4311)
Audio - Volume Control - PGA2310 - TI.com
Electronic Audio Attenuator dc controlled (MC3340)
http://www.datasheetcatalog.org/datasheet/motorola/MC3340.pdf
MAS9116 - Stereo Digital Volume Control
MAS9116 pdf, MAS9116 description, MAS9116 datasheets, MAS9116 view ::: ALLDATASHEET :::
Dual-Channel Digital Volume Control with CMOS switch 4066
http://www.electronicsforu.com/efylinux/circuit/feb2003/aug99_dualchannel.pdf
Digital controlled stereo audio processor TDA7313 (ST)
http://ampslab.com/PDF/tda7313.pdf
http://www.st.com/stonline/stappl/p...type=4&tname=TL_DATASHEET_TREE_X_DOC&latest=N
Maxim DS8102 - the new volume control chip
http://datasheets.maxim-ic.com/en/ds/DS1802.pdf
DS8102 Dual Delta-Sigma Modulator and Encoder - Overview
DIY: high end DAC and digital volume control | Flickr - Photo Sharing!
TDA7439 (Linn Kolektor) THREE BANDS DIGITALLY CONTROLLED AUDIO PROCESSOR (ST)
http://www.datasheetcatalog.org/datasheet/stmicroelectronics/4291.pdf
In the attachement various CMOS solution schematics.
I want to have a good overview about completly kits like the no longer available Vellemann K8022.
Thank you for additional proposals.
(copyrighted images removed by moderators)
Last edited by a moderator:
Take a look at this one:
http://www.diyaudio.com/forums/analog-line-level/184455-preamplifier-lineup-fotios-fun.html
Fotios' homepage: http://www.eal.gr/MICROS.htm
Best regards - Rudi_Ratlos
http://www.diyaudio.com/forums/analog-line-level/184455-preamplifier-lineup-fotios-fun.html
Fotios' homepage: http://www.eal.gr/MICROS.htm
Best regards - Rudi_Ratlos
the lcduino system might be able to do what you want. its now shipping as DIY board sets (and some harder to find parts). you buy the rest of the parts and solder. no case - you do your own case.
The LCDuino-1 Display I/O Processor
it has a choice of vol control engines: PGA for solid state (which I guess you don't like; for whatever reason...) and also relay based (pure analog; but controlled digitally). there may also be other engine plugins later but these are the 2 we support today. there is also i/o switch functionality if you want it. ir uses IR for learning but also has a web back-end coming soon.
is open source code and perhaps one of the more advanced vol control systems out there (yes, I wrote the code, lol).
The LCDuino-1 Display I/O Processor
it has a choice of vol control engines: PGA for solid state (which I guess you don't like; for whatever reason...) and also relay based (pure analog; but controlled digitally). there may also be other engine plugins later but these are the 2 we support today. there is also i/o switch functionality if you want it. ir uses IR for learning but also has a web back-end coming soon.
is open source code and perhaps one of the more advanced vol control systems out there (yes, I wrote the code, lol).
Hi,
I am currently looking for (more or less) the same, just I want to mimic a 12-24 stepped attenuator ladder type. If anyhow possible it should be controlled by up/down switches so I can use a volume button like in the ARC reference preamp.
after a lot of research I am down to these 3 solutions, the Lite Audio V3 (your link to DIY Club) that has the control buttons but is r-2r not ladder tape. DIY gene have it and they also have a nice preamp chassis: Hi End preamplifier Chassis case, Full Aluminum/MK12
This one: Ultimate Remote Volume Control/Selector System | Diy HiFi Supply
I like the LEDs, but it is based on the DS1666 and a bit expensive and has a rotary encoder to manually control the volume.
This I like best but they have not responded to my technical information requests: Parallel remote control potentiometer - $99.95 : hifidiy.net
It is ladder type but it seems to have only 12 steps and I do not know if it can be cascaded. Should be possible to solder a led to each relay to implement the same LED position indication like the DIYhifisupply device.
Maybe this could help you
regards Tom
I am currently looking for (more or less) the same, just I want to mimic a 12-24 stepped attenuator ladder type. If anyhow possible it should be controlled by up/down switches so I can use a volume button like in the ARC reference preamp.
after a lot of research I am down to these 3 solutions, the Lite Audio V3 (your link to DIY Club) that has the control buttons but is r-2r not ladder tape. DIY gene have it and they also have a nice preamp chassis: Hi End preamplifier Chassis case, Full Aluminum/MK12
This one: Ultimate Remote Volume Control/Selector System | Diy HiFi Supply
I like the LEDs, but it is based on the DS1666 and a bit expensive and has a rotary encoder to manually control the volume.
This I like best but they have not responded to my technical information requests: Parallel remote control potentiometer - $99.95 : hifidiy.net
It is ladder type but it seems to have only 12 steps and I do not know if it can be cascaded. Should be possible to solder a led to each relay to implement the same LED position indication like the DIYhifisupply device.
Maybe this could help you
regards Tom
I'm curious, have you look at the lcduino system? why do you insist on ladder? attenuation is attenuation - I don't get why you care how its done.
you can have 127 steps of half db with the delta1/lcduino system. it has the most advanced sofware out there (ob disc: I wrote it, lol). it is also extremely affordable (we went out of our way to use low cost components and not require SMD construction, so its easy to build).
finally, its all open source so you can take its current software base and change if it you need to (but it already does more than any other vol control out there.)
you can have 127 steps of half db with the delta1/lcduino system. it has the most advanced sofware out there (ob disc: I wrote it, lol). it is also extremely affordable (we went out of our way to use low cost components and not require SMD construction, so its easy to build).
finally, its all open source so you can take its current software base and change if it you need to (but it already does more than any other vol control out there.)
Hi,
I guess it is some kind of audiophile paranoia. Having soldered the resistors to some stepped attenuators, I know the ladder type is working perfectly for me.
That is much more than I need. And - at least for me - it is too complex to understand how everything works. Troubleshooting in case of malfunction is hardly possible for me (however, given the price, it might be more clever to purchase a new one). You replaced the caps on your switch, I replaced the caps on my Supermicro dual Socket370 Board some years ago for the same reason. I like to be able to fix things myself.
That is a real big advantage! I did not realise that before. I guess I should be able to build a replacement for the Delta1 to implement a 12 - 24gang ladder type attenuator. and eventually change the software according to make it work. It is still overkill, I know there are chips out there with a simple +/- interface (2 pins connect 1 to ground is +, connect 2 to ground is -) and around 30 output pins at 5V or 12V to drive relays (or LEDs or whatever). I had the resources for such a solution about 5 years ago but lost it.
I will report, maybe I will give the LCDuino a try.
Thanks for mentioning it again,
regards, Tom
I guess it is some kind of audiophile paranoia. Having soldered the resistors to some stepped attenuators, I know the ladder type is working perfectly for me.
That is much more than I need. And - at least for me - it is too complex to understand how everything works. Troubleshooting in case of malfunction is hardly possible for me (however, given the price, it might be more clever to purchase a new one). You replaced the caps on your switch, I replaced the caps on my Supermicro dual Socket370 Board some years ago for the same reason. I like to be able to fix things myself.
That is a real big advantage! I did not realise that before. I guess I should be able to build a replacement for the Delta1 to implement a 12 - 24gang ladder type attenuator. and eventually change the software according to make it work. It is still overkill, I know there are chips out there with a simple +/- interface (2 pins connect 1 to ground is +, connect 2 to ground is -) and around 30 output pins at 5V or 12V to drive relays (or LEDs or whatever). I had the resources for such a solution about 5 years ago but lost it.
I will report, maybe I will give the LCDuino a try.
Thanks for mentioning it again,
regards, Tom
the r-2r style has also worked very well for me, too
I've built at least 10 of them and its just math, really. there's nothing to not work about it. we have a web calculator that does the R selection for you. you pick the # of relays you want (the # of steps) and also the step size (half db, full db, tenth db, whatever). you then buy the R's from that calculator and stuff the boards. oh, and you tell the firmware (via menus) what you built, how many bits and what the step-size is. I usually built 8 bits and half db steps so that gives me 127db of range. way more than you need; but the firmware also lets you set a lower and upper bound and tie those to the min/max of the volume pot (the control element; no audio passes thru it). if you want to use only -80 thru -7, say, you tell the system that (also via menus) and now your 'lock to lock' on the pot is the range you selected. very handy, I think (but again, I wrote it and so I'm highly biased..)one of the goals of the lcduino/volumaster project was to make it as transparent as possible, so you could see thru into the system and change/fix what you need; now or later on. the code does a lot but just ask if you have any questions. we have a support forum for the lcduino series of controllers and plugins.
you will like the lcduino system, then. the hardware and software is all open. all fixable. the arduino that its based on is also fully open and fixable/patchable.
see The delta1 Relay-based R-2R Stereo Attenuator and click on 'resistor calc' on the left. if you want less bits, tell it! no big deal; just install less relays and less R's. jumper from where you left off to 'the other end' of the board (where the other i/o port is) and tell the software. my early builds were 7 relays and 1db steps. if you wanted to save more, go for 6 relays and 1db steps. your choice. you can always add the 'missing' relays and R's later and then just go into menu mode, change the # of bits and it will just plain work. all at runtime, no rebuilding of firmware needed.
This URLs offers only special parts such as pre-programmed MCU and PCB only for diy:
2-channel relay attenuator
http://www.electronicsinfoline.com/...volume_relay_attenuator_with_ir_control.shtml
RelaiXedPassive -- Documentation
https://www.youtube.com/watch?v=Q8aTsjVRDDk
This one use also a small integrated power output stage:
Custom -HIFI Remote Desktop Remote Amplifier PGA2311 fidelity amplifier volume Sanken SK3875 - Taobao Agent Shopping Service in China - Electronics Components Store Taobao
any experiences?
This is my favorite kit, but there is unfortunately a new URL, but this I don't know:
Clickless-Audio-Attenuator.Com: Clickless audio attenuator
Who knows a new web address?
Similar kits:
http://www.tentlabs.com/Products/page31/page31.html
This one consists of several parts for individual using
http://electronics.dantimax.dk/Kits/Control_boards/index.html
http://electronics.dantimax.dk/Kits/Selectors_-_attenuators/11016111312.html (PGA2310 volume control chip PCB)
http://electronics.dantimax.dk/Kits/Control_boards/11016844882_2.html (image display PCB
http://electronics.dantimax.dk/Kits/Control_boards/11016844882.html (operating and display PCB)
http://electronics.dantimax.dk/Kits/1_11450334592.html (RC Transmitter PCB)
http://electronics.dantimax.dk/Kits/11450334592_3.html envelope for RC Transmitter
go also to
http://www.diyaudio.com/forums/parts/92916-dantimax-based-preamp.html
for detail informations
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check out also this thread and the mentioned URLs:
http://www.diyaudio.com/forums/soli...rc-motor-volume-contr-alps-2.html#post4253289
http://www.diyaudio.com/forums/soli...rc-motor-volume-contr-alps-2.html#post4253289
Overview RC Attenuators, sorted
1) RC Attenuator with ICs and Display
Dantimax (elektronik) - Control_boards (both relais+PGA2310, both LCD/LED, various kits)
PGA2311 LCD Volume Remote Control+GOLD RCA Jeff Rowland | eBay (PGA2311, LCD, 70,- €)
PGA2311 Volume Stereo Pre Amplifier Preamp Board with Remote Control and LCD | eBay (PGA2311 LCD, 33 $)
Custom -HIFI Remote Desktop Remote Amplifier PGA2311 fidelity amplifier volume Sanken SK3875 - Taobao Agent Shopping Service in China - Electronics Components Store Taobao (PGA2311, LED, include Power output stage and envelope, 121 $)
CS3310 Crystal Volume Remote Control Preamplifier Kit | eBay (CS3310 LCD, 30 $)
High-End Preamp-Modul mit PGA2311 (Display) (PGA2310, LCD, 70€)
2) RC Attenuators with Relais and Display
Audio and Video | Audio Volume Relay Attenuator with IR Control (relais, LED, price unknown)
2-channel relay attenuator (relais, dot matrix, diy)
Clickless-Audio-Attenuator.Com: Clickless audio attenuator (relais, LED, price unknown)
RelaiXedPassive -- Documentation (relais, LED, only MCU and PCB available)
https://www.youtube.com/watch?v=Q8aTsjVRDDk (relais, LED diy)
Audio and Video | Audio Volume Relay Attenuator with IR Control (relais, LED, price unknown)
DIYCLUB (relais LED 180,- $)
Volume control (relais, LED, 240 €)
2-channel relay attenuator (relais, dot matrix, diy)
The δ1 relay-based R-2R stereo attenuator (relais LCD, various kits)
DIY Kit : hifidiy.net (relais without control board)
Dantimax (elektronik) - Control_boards (both relais+PGA2310, both LCD/LED various kits)
3) RC Attenuator without display (OMNITRONIC LH-125 IC, 50,-- €, include envelope)
Steinigke Showtechnic GmbH | LH-125 IR-Lautstärkeregler | Online Plattform
4) RC Attenuator without display (other)
http://www.conrad-electronic.co.uk/ce/en…-volume-control (vellemann mk163, 16€, sold out)
Velleman nv - International - Overview (vellemann MK163/MK164, TC9143, no longer available)
Introduction and Overview (DS1666 without integrated op-amp)
HD-64 Stufenpotentiometer, Stepped Attenuator, Nur 6 Relais und 6 Spannungsteiler im 6-Bit Binärcode (rel, pot)
Creek OBH-12 Inside - you could use these guts in a DIY project (Creek OBH12/22 pot 600 € include envelope)
https://www.hifituning24.de/zubehoer/fernbedienungen/13501/index.php (pot, 70 €)
1) RC Attenuator with ICs and Display
Dantimax (elektronik) - Control_boards (both relais+PGA2310, both LCD/LED, various kits)
PGA2311 LCD Volume Remote Control+GOLD RCA Jeff Rowland | eBay (PGA2311, LCD, 70,- €)
PGA2311 Volume Stereo Pre Amplifier Preamp Board with Remote Control and LCD | eBay (PGA2311 LCD, 33 $)
Custom -HIFI Remote Desktop Remote Amplifier PGA2311 fidelity amplifier volume Sanken SK3875 - Taobao Agent Shopping Service in China - Electronics Components Store Taobao (PGA2311, LED, include Power output stage and envelope, 121 $)
CS3310 Crystal Volume Remote Control Preamplifier Kit | eBay (CS3310 LCD, 30 $)
High-End Preamp-Modul mit PGA2311 (Display) (PGA2310, LCD, 70€)
2) RC Attenuators with Relais and Display
Audio and Video | Audio Volume Relay Attenuator with IR Control (relais, LED, price unknown)
2-channel relay attenuator (relais, dot matrix, diy)
Clickless-Audio-Attenuator.Com: Clickless audio attenuator (relais, LED, price unknown)
RelaiXedPassive -- Documentation (relais, LED, only MCU and PCB available)
https://www.youtube.com/watch?v=Q8aTsjVRDDk (relais, LED diy)
Audio and Video | Audio Volume Relay Attenuator with IR Control (relais, LED, price unknown)
DIYCLUB (relais LED 180,- $)
Volume control (relais, LED, 240 €)
2-channel relay attenuator (relais, dot matrix, diy)
The δ1 relay-based R-2R stereo attenuator (relais LCD, various kits)
DIY Kit : hifidiy.net (relais without control board)
Dantimax (elektronik) - Control_boards (both relais+PGA2310, both LCD/LED various kits)
3) RC Attenuator without display (OMNITRONIC LH-125 IC, 50,-- €, include envelope)
Steinigke Showtechnic GmbH | LH-125 IR-Lautstärkeregler | Online Plattform
4) RC Attenuator without display (other)
http://www.conrad-electronic.co.uk/ce/en…-volume-control (vellemann mk163, 16€, sold out)
Velleman nv - International - Overview (vellemann MK163/MK164, TC9143, no longer available)
Introduction and Overview (DS1666 without integrated op-amp)
HD-64 Stufenpotentiometer, Stepped Attenuator, Nur 6 Relais und 6 Spannungsteiler im 6-Bit Binärcode (rel, pot)
Creek OBH-12 Inside - you could use these guts in a DIY project (Creek OBH12/22 pot 600 € include envelope)
https://www.hifituning24.de/zubehoer/fernbedienungen/13501/index.php (pot, 70 €)
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for the Velleman kits MK163/MK164 there are no successors - go to
Support Forum (EN/FR) • View topic - Successors for MK163 and MK164 RC Volume control/Attenuator
Support Forum (EN/FR) • View topic - Successors for MK163 and MK164 RC Volume control/Attenuator
RC Attenuator with Relais and Display from Germany
This looks also good
Biino Standard - diy-audio-shop.de
In this case this thread is also of interest:
http://www.diyaudio.com/forums/anal...pop-click-free-hw-based-relay-attenuator.html
I am still looking for te currently webaddress of
http://dawhois.com/www/clickless-audio-attenuator.com.html
Thanks for advices.
This looks also good
Biino Standard - diy-audio-shop.de
In this case this thread is also of interest:
http://www.diyaudio.com/forums/anal...pop-click-free-hw-based-relay-attenuator.html
I am still looking for te currently webaddress of
http://dawhois.com/www/clickless-audio-attenuator.com.html
Thanks for advices.
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I'll say that there are many people who have had problems with Dantimax products.
I have his remote and volume controller and every time you change volume it clicks, you hear this through the SPEAKER! Many of us have asked him to fix this issue, and we have been ignored. I'll have to rebuild my 6sn7 preamp because I designed it with his "kit".
I've read other had good luck with DIY Club also.
Ron
I have his remote and volume controller and every time you change volume it clicks, you hear this through the SPEAKER! Many of us have asked him to fix this issue, and we have been ignored. I'll have to rebuild my 6sn7 preamp because I designed it with his "kit".
I've read other had good luck with DIY Club also.
Ron
fwiw, you cannot have a fully click-free relay attenuator. why? there is no zero crossing detection like there is on the pga, cirrus and other chip-based vol controls.
my own delta1 - while very minimal disruption - still has clicks at big binary rollover points (15.5db to 16db or 31.5db to 32db). can't be avoided. its again due to lack of zero crossing detection. if anyone tells you their relay attenuator is fully click-free, they are lying to you (and again, I and amb have our own design but its not 100% click free during vol changes. just a fact of how that tech works).
my own delta1 - while very minimal disruption - still has clicks at big binary rollover points (15.5db to 16db or 31.5db to 32db). can't be avoided. its again due to lack of zero crossing detection. if anyone tells you their relay attenuator is fully click-free, they are lying to you (and again, I and amb have our own design but its not 100% click free during vol changes. just a fact of how that tech works).
How much trouble would it be to add zero crossing detection to your LCDuino?
I have some ideas on this, but I'm not ready to go public with it yet until I prototype it and see if the idea really works.
its not easy or trivial though. I've never seen zero crossing implemented on a mechanical relay system before. this is a huge benefit of the solid state 'smart' chips. if you look at the cirrus cs3318 (one of my favorite chips, still) it has many options on how it can let you choose the zero crossing method. this should be a hint that zero crossing detection is a 'big deal' and not having it will make the audio vol control changes anything but seamless.
in a nutshell, dc offsets will cause clicks as you vary volume and any instant the wave is not at zero is a form of 'short term' dc offset (if you will) and this is why zero crossing is so important to zipperless vol control systems.
I know of one company that made and sold relay attenuators in commercial products but gave it up when the user base complained about the clickiness of it. so, its a real barrier to sales for many customers; only those who are willing to tolerate the clicks during the vol adjustments will really be happy with the relay approach. otoh, its a very pure method of vol control once you have stopped turning the knob and those that realize this have to make the decision if they are willing to live with the clicks during vol changes to get the benefits of the system during steady-state use.
but there's no simple solution with the relay bangers. so far, I have not seen anyone properly solve it natively. you can minimize the clicks but can't fully get rid of them with a native solution.
its not easy or trivial though. I've never seen zero crossing implemented on a mechanical relay system before. this is a huge benefit of the solid state 'smart' chips. if you look at the cirrus cs3318 (one of my favorite chips, still) it has many options on how it can let you choose the zero crossing method. this should be a hint that zero crossing detection is a 'big deal' and not having it will make the audio vol control changes anything but seamless.
in a nutshell, dc offsets will cause clicks as you vary volume and any instant the wave is not at zero is a form of 'short term' dc offset (if you will) and this is why zero crossing is so important to zipperless vol control systems.
I know of one company that made and sold relay attenuators in commercial products but gave it up when the user base complained about the clickiness of it. so, its a real barrier to sales for many customers; only those who are willing to tolerate the clicks during the vol adjustments will really be happy with the relay approach. otoh, its a very pure method of vol control once you have stopped turning the knob and those that realize this have to make the decision if they are willing to live with the clicks during vol changes to get the benefits of the system during steady-state use.
but there's no simple solution with the relay bangers. so far, I have not seen anyone properly solve it natively. you can minimize the clicks but can't fully get rid of them with a native solution.
MUSES72320
By chance I discover this part from "New Japan Radio":
MUSES72320,MUSES72320V (18V Operation 2-Channel Electronic Volume) | MUSES Official Website
http://www.njr.com/semicon/PDF/MUSES72320_E.pdf
Is this an old or a new device? What about sonic quality ?
Thank you for advices.
By chance I discover this part from "New Japan Radio":
MUSES72320,MUSES72320V (18V Operation 2-Channel Electronic Volume) | MUSES Official Website
http://www.njr.com/semicon/PDF/MUSES72320_E.pdf
Is this an old or a new device? What about sonic quality ?
Thank you for advices.