Thanks very much for the informative and constructive responses.
I will try
and see his stepped attenuators which I would like to try with my amps.
Does he have a web page?
I will try
from memory his ebay user name is alex_550. I will check this when I finish work.
and see his stepped attenuators which I would like to try with my amps.
Does he have a web page?
He doesn't have attenuators-just fantastic switches for making them.
Great. Let me know if he has a link, web page or something.
As far as I know,he only sells through his ebay shop. You can easily find him with his user name.
I guess you have already seen this!
DIY "Lightspeed Attenuator" - Passive LDR Volume Control (audio optocouplers)
Only for interest!
DIY "Lightspeed Attenuator" - Passive LDR Volume Control (audio optocouplers)
Only for interest!
Morgan Jones in hist book has a nice description of attenuators. He has an instruction how to make logarithmic one yourself using switch and SMD resistors.
imho an attenuator quality is pretty audible in good preamp, transformer type attenuators are the best.
imho an attenuator quality is pretty audible in good preamp, transformer type attenuators are the best.
I guess you have already seen this!
Yep seen this and looked interesting, just a shame you can't buy matched pairs easily from manufacturers.
As far as I know,he only sells through his ebay shop. You can easily find him with his user name.
thxs got it. lets have a look.
something like this?
http://cgi.ebay.co.uk/Make-Before-Break-Rotary-Switch-1-pole-23-pos-Set-2-/310211169376?pt=LH_DefaultDomain_0&hash=item483a06cc60
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Many years ago I saw OP12 LDR's used in a box with a lamp.
I dont know what it would sound like. If the lamp failed the volume failed in the low/off state.
Just checking it seems they are not very stable, it might be interesting if there was a better device and use high brightness LED's.
Just for interest!
Regards
M. Gregg
I dont know what it would sound like. If the lamp failed the volume failed in the low/off state.
Just checking it seems they are not very stable, it might be interesting if there was a better device and use high brightness LED's.
Just for interest!
Regards
M. Gregg
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Yes Brit01, either those or some of the spectacular quality ceramic 2 pole ones if you don't feel(as I don't myself) that you need such fine adjustment.The heavily silver-plated contacts are normally a bit tarnished but this easily cleans to pristine brighness and easy solderability using an eraser.(this also works well on silver-plated tube sockets)
dynamic compressors
Photoresistor - Wikipedia, the free encyclopedia
Just for interest after a quick search seems it may still be used!
🙂
Sorry going off topic!
Photoresistor - Wikipedia, the free encyclopedia
Just for interest after a quick search seems it may still be used!
🙂
Sorry going off topic!
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Yep seen this and looked interesting, just a shame you can't buy matched pairs easily from manufacturers.
I dont know if its still available:
http://www.buildanamp.com/2-Light-Dependent-Resistors-LDRs_c2.htm
Not very cheap though!
Regards
M. Gregg
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Passive preamp is being sold already. The Truth Pre AmpI guess you have already seen this!
DIY "Lightspeed Attenuator" - Passive LDR Volume Control (audio optocouplers)
Only for interest!
Discussion link
Passive preamp is being sold already
Nice but a little pricey!
Think I might try some DIY light sensor/photoresistor design myself.
The Perkin Elmer Photoconductive Cell and Analog Optoisolators Data Sheet here is interesting.
http://www.datasheetcatalog.org/datasheet/perkinelmer/VT500.pdf
The VT43N1 looks interesting (VT400 series, page 17).
http://www.datasheetcatalog.org/datasheet/perkinelmer/VT500.pdf
The VT43N1 looks interesting (VT400 series, page 17).
wonder what would happen with 2 LDR's in series per side with middle connection as the output. In at the top, gnd at the bottom.
An LED on each LDR and a voltage adjuster on top "L" & bottom "R" led's to set balance.🙂
Then volume adjust top and bottom LEDs togeather on left or right.
Just a thought.
Regards
M. Gregg
An LED on each LDR and a voltage adjuster on top "L" & bottom "R" led's to set balance.🙂
Then volume adjust top and bottom LEDs togeather on left or right.
Just a thought.
Regards
M. Gregg
Thxs for the link Gregg. I'll read this tonight if I have time.
It has an example of a shunt and series input divider and many other applications.
It has an example of a shunt and series input divider and many other applications.
An LED on each LDR and a voltage adjuster on top "L" & bottom "R" led's to set balance.
Then volume adjust top and bottom LEDs togeather on left or right.
Just a thought.
good ideas here and certainly getting me enthusiastic as an alternative to pots.
Have to have a look at availability and price of the LDR's.
http://cgi.ebay.co.uk/Ceramic-VT43N1-LDR-Photocell-Resistor-400V-400mW-NEW-/220671416124?pt=LH_DefaultDomain_0&hash=item33610a973c
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