Hello again,
I spoke to Uriah on the phone earlier and I've been doing a bit more reading up on voltage dividers since. It seems that as a newbie, A: I didn't really understand how volume controls work (I was basing my assumptions on the idea of series resistance), and B: I probably wired my Lightspeed up incorrectly the first time I tried it, causing it to not attenuate the signal and blow me half way across the room.
I just entered my DMM readings into an online calculator here - Voltage Divider - and found that I should be getting 99.94% attenuation at the minimum volume setting.
I'll try again once I fix my amp. Can't wait!
I spoke to Uriah on the phone earlier and I've been doing a bit more reading up on voltage dividers since. It seems that as a newbie, A: I didn't really understand how volume controls work (I was basing my assumptions on the idea of series resistance), and B: I probably wired my Lightspeed up incorrectly the first time I tried it, causing it to not attenuate the signal and blow me half way across the room.
I just entered my DMM readings into an online calculator here - Voltage Divider - and found that I should be getting 99.94% attenuation at the minimum volume setting.
I'll try again once I fix my amp. Can't wait!
Does anyone by any chance have a spare BSP149 smd mosfet to fit Pauls VCCS boards.
I placed an order with Farnell because there web page intimated that 460 were due for imminent delivery and they've given me a delivery date of Jan 2013!.If anyone can help I would really gratefull.
Thanks
Marra
I placed an order with Farnell because there web page intimated that 460 were due for imminent delivery and they've given me a delivery date of Jan 2013!.If anyone can help I would really gratefull.
Thanks
Marra
Thanks Jack is there a minimum order as this is the only thing I need. I was hoping someone might have a spare one I could buy or do a Trade.
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I am building Pauls VCCS version of the Lightspeed and would like some advice regarding the remote which is the only completed bit so far. Currently waiting for the BSP149 to arrive. When powered led 3 glows continuously. Is this right; I thought it was there as an indicator when a button was pressed. Also what voltages should I have on connections 1 thru 5. Probably showing my ignorance here but its the first build using I.C's. tia.
just a guess for your lack of replies....' building someone else's version '........?
This thread is relating to George's original Lightspeed attenuator - George being the man with the brains behind the whole thing.
Maybe you and Paul should start a new thread....like...
' Paul's VCCS version of an LDR based volume control '
...and remind him not to say the word ' Lightspeed ' because no matter what he has come up with.....it's NOT a Lightspeed - because it's... well....NOT.
Am I becoming like the man from the ' borders ' who uses my name ?
This thread is relating to George's original Lightspeed attenuator - George being the man with the brains behind the whole thing.
Maybe you and Paul should start a new thread....like...
' Paul's VCCS version of an LDR based volume control '
...and remind him not to say the word ' Lightspeed ' because no matter what he has come up with.....it's NOT a Lightspeed - because it's... well....NOT.
Am I becoming like the man from the ' borders ' who uses my name ?
Further back Maximus posted that he had suggested starting a new thread but George had said not to do so which is why I posted here. If this is no longer the case I apologise and due to the lack of responses I guess I should perhaps start another thread.
I am currently using a home built version of Georges excellent attenuator and must say it is one of the best bits of kit I have used in my system and thought it would be interesting to build a remote control unit. My thanks to George for making his design public.
There can only ever be one AndrewT
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I am currently using a home built version of Georges excellent attenuator and must say it is one of the best bits of kit I have used in my system and thought it would be interesting to build a remote control unit. My thanks to George for making his design public.
There can only ever be one AndrewT
:
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I am very interested in building one of these for use with a B22 headphone amp, I am planning on building this in as small a case as possible. I am wondering if it would be possible to use the +1/2 of the sigma22 power supply to feed a small (TO92) sized
lm7805 with a couple of caps as the power for the LEDs, the sigma22 has is a very clean power sorce, so I am assuming that this would result in a very clean voltage to the LED side.Anyone tried this or a similar scheme?
lm7805 with a couple of caps as the power for the LEDs, the sigma22 has is a very clean power sorce, so I am assuming that this would result in a very clean voltage to the LED side.Anyone tried this or a similar scheme?
The .000275% was his calculated distortion, plus the noise floor he says he measured of.000282%
That will be fine even overkill with the Sigma 22, I use a 7805 in my final regulation with nice 470uf smoothing cap then a .1uf MTK and it is indistinguishable from the purest form of dc, battery.
Cheers George
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I noticed its the NSL32SR3 instead of the NSL32SR2 used in the Lightspeed. Why was the NSL32SR3 not used in the Lightspeed? Matching issues?
I found that the impedance spread on the SR3 too great at 60ohm to 25megohm to get quad matching, compared to the much tighter SR2s at 40ohms to 5megohms which will give you much tighter quad matching which also gives a better logarrithmic feel to the volume control because of that quad matching.
The SR2s also goes lower in impedance which give a closer to zero volume than the SR3 can.
Cheers George
The SR2s also goes lower in impedance which give a closer to zero volume than the SR3 can.
Cheers George
?????? I suppose they might if overdriven with 10v or more which may change their internal temperatures, but at normal source levels .5-2v they do not.
Cheers George