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This sounds a little confusing since you mention output impedance numbers then jump to input impedance, I assume for an amp. So to clarify, an 8-10K pot (or equivalent with Tortuga) is good for, but not limited to, 600-1k output impedance for low input impedance amps like say a 26k Class D. A 50k pot or equivalent is good for an amp that has ~47k input impedance, and a 100k pot for amps with even higher input impedances, typically tube amps.Is this what you're saying?
Who da *** is Rex?
Are you interested in Rex's Tortuga?
My buddy Norm says that's a good question.
Nobsound also makes this XLR splitter.https://www.amazon.com/dp/B07D7P7366/ref=twister_B07G525RS7?_encoding=UTF8&th=1
Ok, that made me laugh for a good minute.(sorry Tom!)
I would offer some technical details regarding "passive" preamps. The major function of a preamp is to even out output impedance and to drive interconnect cables between preamp and your amplifier. Believe it or not, those interconnects act as a sort of capacitor which, coupled with output and input impedance, forms a variable RC filter that may affect frequency response in extreme cases of impedance mismatch. A volume pot with no driving buffer followed by a shielded interconnect of significant length may impact sound quality, especially if source output impedance is high enough and amp input impedance is low enough, such as in most solid state gear.Tortuga offers "constant impedance" volume control of around 8-10k that requires output impedance of around 600ohm-1kOhm to drive a typical 26k input stage. 50k pot requires 47k input impedance at minimum, 100k pot is only suitable for tube amplifiers.
Skeptical? So was Rex a friend. It took him three months before he bought a Nobsound.
It's a way of wiring an attenuator, done from scratch it's cheaper than a ladder but still has just two resistors in the signal path - see http://www.goldpt.com/attenuator_types.htmlYou can wire a series attenuator as the shunt element, some claim it sounds better. See Figure 4 here: http://www.moxtone.com/O_stupnjevitom_atenuatoru_2.htm
it's useful for a DIYer because you can use off-the-shelf stepped attenuators.
Just iin case $56 is too cheap for people to buy, this looks like a must have for me that I just now found. A custom made remote passive for $248. Best deal I have found on the internet so far.https://www.audiogon.com/listings/lis9997h-idiom-sspp-1-solid-state
Looks nice but if wanting a remote I'd be more inclined to skip the motorized alps and go for one of the PGA2310/11 preamps:https://www.ebay.com/itm/hifi-PGA2311-Stero-Remote-Volume-Controller-audio-Preamp-pre-amplifier-with-MUTE-/142620463324 They eliminate a physical pot altogether and I was impressed with mine (granted, I modded it of course). I compared with the chinese DACT and the DACT was only a little better. Lot of cheap preamp options out there!
Thanks for sharing this. It sure beats the Axiom II price, but that will probably be my last passive. If everyone could hear a CD player direct into their amp, they would be shocked. I will never understand why people buy an expensive DAC with remote volume, and run it through a preamp.So how much would your mod cost?When I was running my CD player straight in to the Berning amp, another dealer friend from Iowa stopped in for a visit. He was surprised at the sound I was getting out of my system.
