What does the Theta use for an SPDIF receiver? What I have seen in recent SPDIF receivers is essentially 20 pS jitter even with 5 UI jitter going in. The receivers are really good today. The isolation from a good transformer will be better than a USB Isolator. You are trading the USB isolation for the noises from the local supplies. All the ones I have seen use the icron stuff inside. They work but are really pricey. I have one of those as well. I use it for speaker measurements in the field.
The cost vs. price for fiber links seems crazy but its still high. When I ask for quotes for an HDMI 2.0a Fiberoptic cable the OEM quantity price usually starts at $150. The cost of the fiber is essentially zero so its in the asics at each end. The VCSEL and receiver diodes are cheap. Assembling it is not cheap today (not very automated yet) and the volume is very low. So perfect for audiophiles. What I would do (to drive the audio market nuts) is use Infiniband fiberoptic cables for I2S. 4 Multi-Gigabit links in neat machined housings with something like petabyte error rates.
The cost vs. price for fiber links seems crazy but its still high. When I ask for quotes for an HDMI 2.0a Fiberoptic cable the OEM quantity price usually starts at $150. The cost of the fiber is essentially zero so its in the asics at each end. The VCSEL and receiver diodes are cheap. Assembling it is not cheap today (not very automated yet) and the volume is very low. So perfect for audiophiles. What I would do (to drive the audio market nuts) is use Infiniband fiberoptic cables for I2S. 4 Multi-Gigabit links in neat machined housings with something like petabyte error rates.
VCSEL's don't not readily lend themselves to silicon waveguide applications They package best with TO can based coaxial or TOSA packages because of the "V" in VCSEL. So again, Need to talk to the photonic folks at Corning and find out. I say they are Fabry Perot lasers.
Theta used a plain silicon PD. It is fast enough for that application. Yes toslink , the new stuff is faster, but then the fiber leave a lot to be desired and the combination of short fiber length and high index reeks havoc on the signal. A whole slew of problems you haven't even addressed. That is why I OEM'ed fiber for AudioQuest ans Straightwire and produced the accesries Theta old for their fiber links - back in the day.
Assembling a VCSEL coax or TOSA pigtail cost about 100 bucks. But it wouldn't be my choice for this application. I would go with a DFB (Distributed Feedback) laser.
Theta used a plain silicon PD. It is fast enough for that application. Yes toslink , the new stuff is faster, but then the fiber leave a lot to be desired and the combination of short fiber length and high index reeks havoc on the signal. A whole slew of problems you haven't even addressed. That is why I OEM'ed fiber for AudioQuest ans Straightwire and produced the accesries Theta old for their fiber links - back in the day.
Assembling a VCSEL coax or TOSA pigtail cost about 100 bucks. But it wouldn't be my choice for this application. I would go with a DFB (Distributed Feedback) laser.
Since digital is being discussed... Have any of you followed the work of John Brown (ECDesigns) on digital? Excellent work in my opinion and he truly believes in his products.
Again why? Packaging is always an issue and I see no need to pay for properties that have no benefit in the application. Telecom performance (and $$) for Red Book digital audio seems typical audiophile territory. We were doing 100 meter HDMI 2.0, BOM was far less than $100 (not including cable), no one wanted it in the end.
EDIT - Missed Demian's comment, by no one wanted it I meant the volume was not there to spend the NRE for a path to get the assembly costs down.
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The issue is Die Bonding. The system line Corning's USB or the HDMI work on a silicon wave guide. If you Mount a VCSEL (vertical-cavity surface-emitting laser) on the substrate, it will be pointing the wrong way!
I know a few AV installers who waste a lot of time chasing video interference during their installs. They welcome fiber HDMI.
Personally, If I here a difference, I will peruse it. This is DIYAudio, is it not?
I know a few AV installers who waste a lot of time chasing video interference during their installs. They welcome fiber HDMI.
Personally, If I here a difference, I will peruse it. This is DIYAudio, is it not?
Flex circuit daughter cards, DVD players have several. Take apart a multi-format player and then realize the BOM for the entire optical path is <$2 power lasers and all, it's all volume.
BTW I never tried any DIY experiments but have some VCSEL's in LED packages, I was thinking drill a little hole and set some cheap fiber into it with UV glue and see what I get out.
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I had a Friend who worked in at Philips back in the day. I remember him saying the whole CD transport cost something like $8. Which is amazing to me. Voice coils, optics, alignment, motors, plastic, springs.....amazing
As a rule unless the light is very good I can't read the print on the spine of a CD case, so staring at the shelf does me no good. I ripped all my CDs and have been using a Squeezebox. The remote is the best part, I can quickly scan through artists/albums to find something. Could also use a browser on phone/tablet/whatever, but I like the UI on the squeezebox remote, it's like an old ipod. Plus radio!
LP's are harder, I have to partially pull them out from the shelf to see a bit of the cover to figure out what they are (with a few exceptions).
Hmm they have dropped the core HW requirements since I last checked. Still more grunt than my server has, so would need a new machine. Tricky as mpd does all I really need, I just want a tablet that is dedicated to the control task.
I get the seeing the labels, some on here have 25 years on me but I'm already on varifocals having been wearing glasses since I was 9. I have 3 racks (about 42" wide in total) where I need a torch to see whats in them, but the main rack is next to the sofa and I have a lamp so can see the spines.
The great thing about the 21st century is the sheer choice of delivery methods for good music. And the snobbery of the past is gone, so we can mix and match as we please.
I get the seeing the labels, some on here have 25 years on me but I'm already on varifocals having been wearing glasses since I was 9. I have 3 racks (about 42" wide in total) where I need a torch to see whats in them, but the main rack is next to the sofa and I have a lamp so can see the spines.
The great thing about the 21st century is the sheer choice of delivery methods for good music. And the snobbery of the past is gone, so we can mix and match as we please.
My gast is flabbered that any of these media server types are at all hardware dependent. We're talking pretty pedestrian data streams here; even a RPI2 has enough oomph to do a full-blast DSP and run MPD.
You are right DPH and Bill, all you need is like and i3 and 4 gigs of RAM. not much for the OS. With a Intel NUC, about $300. I run mine headless and use a refurbished Nexus 10 tablet for the GUI. Electrical noise and ground bounce seems to affect the data stream resulting in more error correction, which is what you hear. That is why I am using a minimalist linux install. But ROON has since solved this with a ROCK, their custom linux.
Anyway, I am going blind too. And it's fun to explore the metadata and where they link to other albums etc. while listening.
Anyway, I am going blind too. And it's fun to explore the metadata and where they link to other albums etc. while listening.
I didn't think you were old enough to remember Frankie Howerd 🙂
Roon needs grunt for all the metadata it deals with (hence the SSD requirement) as it slurps in all sorts of stuff from the internet to give you an 'experience'. MPD can scan a terabyte of disc for what it needs in under 5 minutes. Very different approaches and If you like to turn the lights low, close eyes and immerse in a soundworld, Roon is overkill.
Roon needs grunt for all the metadata it deals with (hence the SSD requirement) as it slurps in all sorts of stuff from the internet to give you an 'experience'. MPD can scan a terabyte of disc for what it needs in under 5 minutes. Very different approaches and If you like to turn the lights low, close eyes and immerse in a soundworld, Roon is overkill.
I doubt I was, Bill. 🙂
I still feel about equally comfortable with a shell terminal to a GUI in Linux, so all that extra fru fru is really lost on me, gotta admit. Just give me the music already!
I still feel about equally comfortable with a shell terminal to a GUI in Linux, so all that extra fru fru is really lost on me, gotta admit. Just give me the music already!
I generally use locate from command line to find if I have music, or where I filed it. Not yet tried to learn the MPD command line. Really ought to sometime.
Problem is I've got 8000* albums on the server. takes a while to skim 🙂
*and yes I know things got a bit out of hand on the music buying for a while.
*and yes I know things got a bit out of hand on the music buying for a while.
That is the hardest part of the music server. ripping all the disks. I bought a used robotic duplicator and turned it into a batch ripper using dBPowerAmp software. It did 100 disks at a time, Batch in morning, Batch at night
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