Switchable Hi-Z input impedance, how ? - Page 47 - diyAudio
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Old 4th March 2013, 06:31 PM   #461
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by Nigel Goodwin View Post
It has no effect at all - it's purely imaginary
its funny, but every time you have said that, I have tested it, just to see if you could be right

but no, I have to disappoint you and say; it does make a small difference

with balance turned towards the bass output connected to the woofer amp, I get a bit more forward low bass
and at the same time the upper register turns slight dry, with the pitch going down a just bit on the sustain
not easily heard, but the change is there, 100%

turning balance pot the other way, towardsmid/tweeter output, connected to ....the pitch stays up with more prolonged sustain
at the same time the low bass seems to get a bit more smooth and soft, with less attack

small changes
but you know how these small things matter when playing the finer tunes

btw, increasing the series resistor after attenuation pot to 470ohm made it slightly brighter, and more airy
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Old 4th March 2013, 07:20 PM   #462
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Quote:
Originally Posted by tinitus View Post
its funny, but every time you have said that, I have tested it, just to see if you could be right

but no, I have to disappoint you and say; it does make a small difference

with balance turned towards the bass output connected to the woofer amp, I get a bit more forward low bass
and at the same time the upper register turns slight dry, with the pitch going down a just bit on the sustain
not easily heard, but the change is there, 100%
Sorry, I don't believe you, the difference is absolutely too small to measure, never mind hear.

You're not helping your cause by using imaginary meaningless terms like 'forward' and 'dry' either.

Quote:

turning balance pot the other way, towardsmid/tweeter output, connected to ....the pitch stays up with more prolonged sustain
at the same time the low bass seems to get a bit more smooth and soft, with less attack

small changes
but you know how these small things matter when playing the finer tunes

btw, increasing the series resistor after attenuation pot to 470ohm made it slightly brighter, and more airy
More imaginary terms

Why not just wire the pan pot correctly - just add four resistors (or just the first two would do) - with your 4.7K pot, drop the 3.3K resistors to 1.5K or 1.8K, this would then give you a proper working pan pot.

Consult the circuit attached.
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File Type: gif pan_pot.gif (8.3 KB, 21 views)
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Old 4th March 2013, 07:57 PM   #463
tinitus is offline tinitus  Europe
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Quote:
Originally Posted by Nigel Goodwin View Post
Sorry, I don't believe you.....
no, thats very clear, but thas fine with me
I know it works as described
but with a distorted guitar its not likely to work

Quote:
Originally Posted by Nigel Goodwin View Post
You're not helping your cause .....
actually, it works so nice that I still consider something similar in my next preamp, but with a 5 position rotary switch instead

and ofcourse combined with additional seperate channel attenuators
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Old 4th March 2013, 08:03 PM   #464
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Quote:
Originally Posted by Nigel Goodwin View Post

Why not just wire the pan pot correctly....
pan pot ?
as I understand it, a pan pot feeds part of a 'foreign' signal from one channel to opposite channel
would be more a blend or mixing thing, and the opposite of splitting a signal, is it not ?
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Old 4th March 2013, 08:17 PM   #465
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ok, I se your 'pan pot' version now

signal feed to each 'side' of the pot, and wiper is 'ground control'

ground control calling...he

that seem fairly easy to try without making too much mess
thanks Nigel, I might give it try
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Old 4th March 2013, 08:22 PM   #466
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and maybe change attenuator to a stereo pot

one of those with seperated concentric shaft would be nice
they are not easy to find, but I have seen one for guitar use
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Old 4th March 2013, 08:32 PM   #467
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hey, with a linear stereo att/pot, there might be a fun option

using different paralel resistors for each channel, could result in a interesting function

I think you would call it 'having different law' for each channel

with a switch..
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Old 4th March 2013, 10:20 PM   #468
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and the crazy idea....linear stereo att pot with variable law/log
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Old 5th March 2013, 07:59 AM   #469
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Originally Posted by tinitus View Post
and the crazy idea....linear stereo att pot with variable law/log
'Crazy' as in you've altered it at random to stop it working.
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Old 5th March 2013, 09:12 AM   #470
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decided to finish this box for the next preamp project
and maybe I will construct a new sub chassis
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File Type: jpg IMG_8576.JPG (156.3 KB, 16 views)
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