If I wanted to use some of my spare M2X daughter boards as a buffer in another project, how does one implement the grounding?
^ Exactly. There could be a 0V reference point though...
For some fun - Check out how the Austin front end was used with an F6. I think it was @TungstenAudio that enjoyed that combination and posted how they implemented the integration. Also, I am pretty sure that @xrk971 did a version of the AKSA Lender as a front end to integrate with the M2x. Those are two off the top of my head that may help with various situations you could run into depending on which card you're using with what type of amp.
I'm going by memory... so apologies if it's a bit off. May search later when I get home and link if you can't find either.
For some fun - Check out how the Austin front end was used with an F6. I think it was @TungstenAudio that enjoyed that combination and posted how they implemented the integration. Also, I am pretty sure that @xrk971 did a version of the AKSA Lender as a front end to integrate with the M2x. Those are two off the top of my head that may help with various situations you could run into depending on which card you're using with what type of amp.
I'm going by memory... so apologies if it's a bit off. May search later when I get home and link if you can't find either.
Ok, so leave it floating as it is in the M2x then.
Just follow the same approach.
Ground is a state of mind, as ZM said, and in your case probably not very relevant.
As there's no ground connection, there's no new ground loop. Therefore no need to worry.
Still, check the examples IAIMH provided above.
I know I could be wrong, so do your homework.
Just follow the same approach.
Ground is a state of mind, as ZM said, and in your case probably not very relevant.
As there's no ground connection, there's no new ground loop. Therefore no need to worry.
Still, check the examples IAIMH provided above.
I know I could be wrong, so do your homework.
Good Morning DIY community, I have all the components for the Milpitas card, I was checking to see if any of the awesome members of the community have extra blank boards they were willing to part with. I live in North Carolina.
Thank you for all you do! Kelly
Thank you for all you do! Kelly
Had a snafu with my M2X. I control volume in the digital domain because the attenuators without question affect the low end in my setup. A lot. According to my SPL meter I rarely listen above 80db, fwiw. So I keep everything but the source software, on this day it was Spotify, all the way open. I just always use the same order of operations...start with everything all the way down, closed - then open the Iron Pre up, followed by Windows - then slowly turn up Spotify to find the desired volume ( usually about half way ).
This worked awesome until Spotify/Windows glitched and sent what was obviously a full signal out the moment I touched the volume slider. No slip, no accident, no mouse movement; touch, LOUD.
After that I could tell it didnt sound right so I threw in a different DAC, sounded the same. Checked the Iron Pre: no offset, same as the day I dialed it in. The M2x, however, had 200mv of offset presenting on the right channel. I tried re-adjusting it buts its still super jumpy and doesnt want to settle at 0. The left channel is behaving fine.
Best way to describe the sound, while I had it connected, is....out of phase. Not sure whats happening with the right channel but something was obviously affected by getting 4V ( 2V from schiit bifrost into the Iron Pre -> M2X ) for a brief moment.
This worked awesome until Spotify/Windows glitched and sent what was obviously a full signal out the moment I touched the volume slider. No slip, no accident, no mouse movement; touch, LOUD.
After that I could tell it didnt sound right so I threw in a different DAC, sounded the same. Checked the Iron Pre: no offset, same as the day I dialed it in. The M2x, however, had 200mv of offset presenting on the right channel. I tried re-adjusting it buts its still super jumpy and doesnt want to settle at 0. The left channel is behaving fine.
Best way to describe the sound, while I had it connected, is....out of phase. Not sure whats happening with the right channel but something was obviously affected by getting 4V ( 2V from schiit bifrost into the Iron Pre -> M2X ) for a brief moment.
Also...with my listening habits a Pumpkin/AVC may be in my future. Perhaps safer than this approach, which I knew would eventually have some consequences.
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Annndddd in the spirit of exploration I switched out my multimeters to two different ones, with fresh batteries, and was able to dial in the right channel with those 🤦♂️
I’ll try it, thank you ZM.
Other downside is that I almost never use my record player because the low end is so attenuated. This alone has me curious about AVCs. I want to play my records more often.
The shape of my room is obviously also a big factor. I know I have a few spots that really “trap” bass and need treatment, and a properly eq’d sub could definitely even things out where I sit. I don’t have one yet. On the upside…the room has fewer parallel walls to the sides than most houses so I always get a glorious wide, deep soundstage. Bass is the challenge.
Other downside is that I almost never use my record player because the low end is so attenuated. This alone has me curious about AVCs. I want to play my records more often.
The shape of my room is obviously also a big factor. I know I have a few spots that really “trap” bass and need treatment, and a properly eq’d sub could definitely even things out where I sit. I don’t have one yet. On the upside…the room has fewer parallel walls to the sides than most houses so I always get a glorious wide, deep soundstage. Bass is the challenge.
Using the attenuators in the iron pre kills the low end...night and day 🙁. Only way to bring it back is to max them out then turn it down on the digital side.
Could it be the alps pots I used? It was these, from Parts Express: ALPS RK27 20KA Audio Taper Potentiometer
Could it be the alps pots I used? It was these, from Parts Express: ALPS RK27 20KA Audio Taper Potentiometer
any type of inductive attenuator is much!!!! more dependable of proper buffering than any type of resistive attenuator, simply because inductive presents variable impedance in function of frequency, while resistive we can take as constant impedance in frequency domain
so, if you have unbuffered AVC (or TVC), that's recipe for trouble, avoided only of fed directly from source having Gargantuan Cojones, with short and benign signal cable/interconnect
if you have unbuffered resistive attenuator, there is usually no loss in frequency extremes, but dynamics are sorta measly
reminder - with inductive - buffer goes in front, with resistive - buffer goes afterwards
if Real McCay ALPS, let's believe in quality of part, so say that first thing I'm thinking of is - what source you're using, if killing low end?
for 20K pot, Rout of source must be lesser than 500R, ideally bellow 100R
and, let's not forget value of coupling cap, if there is one
I did saw constructions of reputed manufacturers, having some sort of buffer at end, while coupling cap being way too small in value
Sources for digital are a Schiit Bifrost 2/64, their Modi MultiBit prior to that. For vinyl: Hagerman Bugle 2.
Bifrost 2/64 spec:
Outputs: RCA (single-ended) and XLR (balanced)
Output Impedance: 75 ohms for both
Could it be the coupling cap I used in the M2X? CB3? It was a 1uf film, 50V.
BA3-FE or Wayne's 2018 pre into the F4 didnt have this issue. With those I would dial the volume on the preamkp to a much lower spot then control volume on the digital side. Didnt have to pin the pots open, for sure.
Bifrost 2/64 spec:
Outputs: RCA (single-ended) and XLR (balanced)
Output Impedance: 75 ohms for both
Could it be the coupling cap I used in the M2X? CB3? It was a 1uf film, 50V.
BA3-FE or Wayne's 2018 pre into the F4 didnt have this issue. With those I would dial the volume on the preamkp to a much lower spot then control volume on the digital side. Didnt have to pin the pots open, for sure.
nope, what I meant is - possible coupling cap in front of ALPS 20K
nothing to have with amp side, while speaking of preamp and sources