Originally Posted by pabbi1
(only 23 steps)
I have to say that I find this to be one of the most curious notions in all of DIY audio. Do you guys really use all
23 steps from top to bottom and still find that there just aren't enough? Or, what seems more likely, do you use a small portion of the range, but find the nature of 23 steps means that, within the range you want to use, there are only 4 or 5 steps while you would really like 9 or 10?
It seems like it would make more sense to just get the gain of the system right in the first place, and then use some mechanism for adding a few steps around the listening range to account for particular recordings, or moods. Use a regular 23, or 12 position switch, but put it in 1 or 2dB increments right around your range. Then add a few large steps at the margins for when you want to test just how loud your amp can go.
The whole point of DIY (among the other whole points of DIY) is that you can build gear just for you -- you don't need to adhere to manufacturer conventions, or do things how they were always done. Instead, you can figure out what works for you and implement it. The whole notion that one's own amp would need 48dB worth of attenuation simply says that the amp has some design problems.
My current amp
, for instance, uses an attenuator with 12 steps. I only have 6 of them wired up, and in fact have only ever used 3. The reason this works is that it is build for my ears and my source, and so is just right for me.
And yes, I understand that some people use multiple phones and sources, but in that case, maybe a switch to switch between High Z and Low Z, or some sort of gain adjustment might be useful.
I might point out, too, that the attenuation method used is a huge step up from a resistive attenuator which throws away signal as heat and mucks with impedance. Resistive attenuators, no matter how well made, are always detrimental. But, a well implemented TVC or AVC actually improves drive capabilities as you attenuate.