Somebody can tell me what pot is used in this preamp? It has 4 connections per channel (so 8 for stereo). It's from a NAD preamp and the volume pot is used in part for the loudness-correction. What does it do? How does it work? Where these pots can be bought (how do you call them: 4 pin pots?).
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And sorry I see that same kind of question is dealt with here: Volume Pot with 4 legs ?!!! If someone can add to this? These are specially designed loudness-pots for 70-ties amps and now out of fashion.
Is there a way to replicate this circuit with a normal 3-pin pot by using some trick? Assuming I can't find such a volume pot with same dimensions and reasonable price that is. (answer from former discussion of 2004: no you can't!).
And wrestling with how to model such a pot in SPICE. I can simulate a normal 3 pin pot by doing steps from a resistor netwerk where one resistor is X and the other (20k-X). But don't see a way to have a new connection at the same resistor netwerk attached to a fixed 40% of the total value of 20k (ie 8k indepent of the step chosen in the simulation). Some clever guys must have found ways of dealing with this right?
Is there a way to replicate this circuit with a normal 3-pin pot by using some trick? Assuming I can't find such a volume pot with same dimensions and reasonable price that is. (answer from former discussion of 2004: no you can't!).
And wrestling with how to model such a pot in SPICE. I can simulate a normal 3 pin pot by doing steps from a resistor netwerk where one resistor is X and the other (20k-X). But don't see a way to have a new connection at the same resistor netwerk attached to a fixed 40% of the total value of 20k (ie 8k indepent of the step chosen in the simulation). Some clever guys must have found ways of dealing with this right?
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"Volume pot with loudness tap." Below a certain level, the circuit boosts the bottom end some to compensate for your hearing. Note your circuit has an on/off switch for it. Many people turn it off. Many amps also have it as a separate button on the control panel, and use a regular volume pot.
Google "loudness control" for lots more information.
Google "loudness control" for lots more information.
While the denon 250III on my bench today has no loudness button, it also has the 8 pin volume control. Been scratching my head over it a while! 🙂
It seems in direct, the volume uses 6 connections. Then when the controls are bought in, they supply the same pins as the direct switch, but the tone circuits also send another signal out too the end two pins. My tone area is down so I can't look at these extras. From the talk above, they inject some signal towards the end of the tracks.
This amp only works on direct. I could trash it for the volume pot if your need is greater. It's only a 50 euro amp fixed
It seems in direct, the volume uses 6 connections. Then when the controls are bought in, they supply the same pins as the direct switch, but the tone circuits also send another signal out too the end two pins. My tone area is down so I can't look at these extras. From the talk above, they inject some signal towards the end of the tracks.
This amp only works on direct. I could trash it for the volume pot if your need is greater. It's only a 50 euro amp fixed
My amp works allright and also is in that price-range🙂. I mainly want to understand the workings and maybe want to change the circuit by adapting some values. Now the bass boost is much much too wild (more like +10db or more) and also working till very high levels of volume (not wanted, since loudness correction is needed only a low volumes).
Maybe I want to replicate the circuit for testing purposes and get some feel by what it does and how to make it usefuller as it now is.
Of course I can look for a complete new way of bringing in loudness effects that do work (since I've found out at my age and listening at very low volumes that I do need some correction in tone, listening straight or linear is very unsatisfying and normal bass and trebel pots can't do much for that, wrong region, too course etc).
So maybe thinking again along these lines, my question also is: how to make a flexible loudness-facility for low volume listening that is satisfying to the ear (maybe some positions to choose from) and easy to implement.
Maybe I just need an equalizer in the end ....
Maybe I just need an equalizer in the end ....
Yeah, right, the NAD 310 is an oddball amp. It also has asymmetrical power supply and a big electrolytic cap in the output rails. Maybe a forerunner in 'retro-amps' (though I think the Audio Innovations Alto did something like this without the loudness some years before 1999).
Ah now I see: the 'loudness-tapped' pot is NOT used for loudness but is used for the setting 'tone defeat' and arranges for a smooth transition between switching tones in and out.
Ah now I see: the 'loudness-tapped' pot is NOT used for loudness but is used for the setting 'tone defeat' and arranges for a smooth transition between switching tones in and out.
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