Hey all,
Long time listener, first time caller. I'm an attorney with an undergrad physics degree, so I've taken electronics classes, but never had to independently engineer anything (nor do I remember much of what I learned back then beyond the bare necessities). Am still playing around with CMoys and all that to get my basic sautering skillset up to par. So y'know. Noob.
I'd like to make an all-in-one streaming unit. I was thinking something like a raspberry pi (with raspyfi or squeezeplug) with a wireless USB dongle and an ODAC filling the USB ports, with the ODAC outputting to a three-way switch: speaker stage, headphone stage, and line-out. Speaker stage would be linked to a pair of Linkwitz Pluto clones: the ODAC line-out would go through a minidsp 2x4 balanced unit, then out at line level into faux-Plutos with small, prefab (i.e., not DIY) power amps in their bases. The headphone stage would go through a Meier crossfeed (lifting from the Corda Cross-1), then into an O2.
The main idea is to build something that checks all the boxes without breaking the bank, while allowing for some later upgrades (building the crossover and amplification for the Plutos to spec, for instance); something to tide me over for a while.
Being an EE ignoramus, I had a few questions and would appreciate any other guidance you all could offer:
1. Impedance into the crossover circuit. The original Corda Cross-1 had six-position bass and treble switches to account for input and output impedance. I seem to recall reading that the ODAC had an output impedance of about 40 Ohms, while the O2 has "Input impedance >= 10K" (source). I am not entirely sure what that last figure means (10 KOhms?), and am not sure quite how to account for it in the crossover design. I think I can pull out the resistors used for the appropriate switch positions (the Corda Cross-1 manual lays these out), but would appreciate any guidance you all have on that point.
2. I am really lost on how to power this thing. I'm fine with using up half a power strip to power discrete components when I'm clumsily breadboarding this monster, but after that I'd like to have everything running of a single plug. I apologize if this is overly ignorant, but is that a matter of good voltage regulators, independent power circuits for each component, some multi-rail power supply pcb, or something I've missed? Just trying to narrow the field of what I need to research.
3. Thoughts generally? I like the idea of taking all my functions and squeezing them into a single box. My collection is all digital at this point, so I have no need for fancy phono pre-amp stages or anything like that. I'm just not sure of the soundness of this plan from an engineering point of view (e.g., wifi dongle interfering with the internal electronics, the effect of having all these components in a tight space, etc.). I'm not looking for absolute electronic perfection, but I'm picky enough that I'd rather spend some time on the front end planning it out than overhauling it down the road.
Thanks for any input you may have!
Long time listener, first time caller. I'm an attorney with an undergrad physics degree, so I've taken electronics classes, but never had to independently engineer anything (nor do I remember much of what I learned back then beyond the bare necessities). Am still playing around with CMoys and all that to get my basic sautering skillset up to par. So y'know. Noob.
I'd like to make an all-in-one streaming unit. I was thinking something like a raspberry pi (with raspyfi or squeezeplug) with a wireless USB dongle and an ODAC filling the USB ports, with the ODAC outputting to a three-way switch: speaker stage, headphone stage, and line-out. Speaker stage would be linked to a pair of Linkwitz Pluto clones: the ODAC line-out would go through a minidsp 2x4 balanced unit, then out at line level into faux-Plutos with small, prefab (i.e., not DIY) power amps in their bases. The headphone stage would go through a Meier crossfeed (lifting from the Corda Cross-1), then into an O2.
The main idea is to build something that checks all the boxes without breaking the bank, while allowing for some later upgrades (building the crossover and amplification for the Plutos to spec, for instance); something to tide me over for a while.
Being an EE ignoramus, I had a few questions and would appreciate any other guidance you all could offer:
1. Impedance into the crossover circuit. The original Corda Cross-1 had six-position bass and treble switches to account for input and output impedance. I seem to recall reading that the ODAC had an output impedance of about 40 Ohms, while the O2 has "Input impedance >= 10K" (source). I am not entirely sure what that last figure means (10 KOhms?), and am not sure quite how to account for it in the crossover design. I think I can pull out the resistors used for the appropriate switch positions (the Corda Cross-1 manual lays these out), but would appreciate any guidance you all have on that point.
2. I am really lost on how to power this thing. I'm fine with using up half a power strip to power discrete components when I'm clumsily breadboarding this monster, but after that I'd like to have everything running of a single plug. I apologize if this is overly ignorant, but is that a matter of good voltage regulators, independent power circuits for each component, some multi-rail power supply pcb, or something I've missed? Just trying to narrow the field of what I need to research.
3. Thoughts generally? I like the idea of taking all my functions and squeezing them into a single box. My collection is all digital at this point, so I have no need for fancy phono pre-amp stages or anything like that. I'm just not sure of the soundness of this plan from an engineering point of view (e.g., wifi dongle interfering with the internal electronics, the effect of having all these components in a tight space, etc.). I'm not looking for absolute electronic perfection, but I'm picky enough that I'd rather spend some time on the front end planning it out than overhauling it down the road.
Thanks for any input you may have!