Not just that, but there should be no need to spend too much on the problem. Even if you can easily spend $150 on a UPS for it, it would be silly to do, when you're already DIYing the rest of it.
If you were getting a mains UPS that will handle some audio equipment, which is likely to use linear transformer and rectifier based PSUs, I would suggest going for sine wave ones, used so they're more affordable. Stepped sine usually causes noise when it has to kick in (it's all DC), and it might not be good for some PSUs. That's quite overkill for this scope of project, though.
Last edited:
Yeah I am going to keep the spots for the optional battery, R, and C - but other than that I am not going to spend more time on it. 
Just now I did test a bog standard $60 UPS with shutdown hook (USB) and it worked like a charm even with a USB drive and Wifi connected. Nice thing about that is it does not shutdown until it really needs to.
Just now I did test a bog standard $60 UPS with shutdown hook (USB) and it worked like a charm even with a USB drive and Wifi connected. Nice thing about that is it does not shutdown until it really needs to.
I just noticed this: 4 313042 526329 - CW2 - UNINTERRUPTIBLE PSU, FOR RASPBERRY | CPC
Looks interesting, I thought.
Looks interesting, I thought.
So over the past few days I connected a Pi to my DAC via I2S (not a TP Dac, sorry). The actual connection is just 6 wires, 3 grounds and 3 signals. Wires are only a couple inches long, but I made them all twisted pairs.
I am running picoreplayer in the Pi, and have a headless, fanless PC running Daphile which performs the music server function.
For now, I have the Pi powered by a 4400 Mah generic USB type battery.
For a simple, low cost setup, I'm very impressed by how good it sounds.
Thanks for suggesting this. I think that removing USB is a good think, it creates a very short, simple signal path. I also like picoreplayer because it just plays music, and is a very small file. It was also easy to setup for I2S, just selected the I2S Dac option and it made music.
I have a BBB waiting, looking forward to trying that.
Randy
I am running picoreplayer in the Pi, and have a headless, fanless PC running Daphile which performs the music server function.
For now, I have the Pi powered by a 4400 Mah generic USB type battery.
For a simple, low cost setup, I'm very impressed by how good it sounds.
Thanks for suggesting this. I think that removing USB is a good think, it creates a very short, simple signal path. I also like picoreplayer because it just plays music, and is a very small file. It was also easy to setup for I2S, just selected the I2S Dac option and it made music.
I have a BBB waiting, looking forward to trying that.
Randy
element14 clones of BBB works fine too. I've also tested I2S transfer between Circuictco BBB and element14 BBB and it worked...
I don't think the Element14 boards are clones, they are the genuine Ciucuito made ones.element14 clones of BBB works fine too. I've also tested I2S transfer between Circuictco BBB and element14 BBB and it worked...
Designed, but not made. Also RMA is separated.
The element14 BBB does not have beaglebone logo, neither beaglebone.org writing. Official support page is at different too: http://www.element14.com/element14_BBB
"element14 BeagleBone Black is a BeagleBoard Compliant design available from element14"
But this version seems to be also sold out...
The element14 BBB does not have beaglebone logo, neither beaglebone.org writing. Official support page is at different too: http://www.element14.com/element14_BBB
"element14 BeagleBone Black is a BeagleBoard Compliant design available from element14"
But this version seems to be also sold out...
Last edited:
Mmm, looks like the Rev C ones are manufactured by Element14. From their website: "Manufacturer: ELEMENT14". Certainly the Rev A one I got from them was made by Circuitco.
Possibly because Circuitco couldn't keep up with demand?
Physical Implementation...
Working on building my new DAC based on this development.
I know the BBB and Botic are designed to stack onto the Buffalo 3, nice and neat/compact, but is that the best solution or is there a risk of interaction/interference? Would I be better putting the BBB/Botic into a separate chassis and connecting via teleporter modules and, if I did, will I lose out on anything?
What do you guys think?
Ray
Working on building my new DAC based on this development.
I know the BBB and Botic are designed to stack onto the Buffalo 3, nice and neat/compact, but is that the best solution or is there a risk of interaction/interference? Would I be better putting the BBB/Botic into a separate chassis and connecting via teleporter modules and, if I did, will I lose out on anything?
What do you guys think?
Ray
nautiboy: Nope, BBB with Botic will not be stackable on TPA DACs.
Possible interferences:
- (large) USB Wifi close to the BBB or DAC
- (large) ground loop if BBB is in different box (and no Teleporter)
- (medium) BBB very close to the DAC
- (medium) USB connected to BBB
- (small) Ethernet connected to BBB
And possibly others...
Possible interferences:
- (large) USB Wifi close to the BBB or DAC
- (large) ground loop if BBB is in different box (and no Teleporter)
- (medium) BBB very close to the DAC
- (medium) USB connected to BBB
- (small) Ethernet connected to BBB
And possibly others...
Hens teeth I can get, it's the replacement fairy wings I have trouble getting.....
No, just really popular. Newark (a U.S. Farnell presence) showed them in stock with an email just like you got, but were out of stock by the time I tried adding one to my cart. I ended up unable to find them from many stores, and ended up getting it from Adafruit, which had showed them as OOS earlier on the same day.
Those being such concerns, how far can I2S realistically be brought out, just as plain twisted, er, wires?
My misunderstanding, thanks for clearing that up. But....
The Botic is designed to stack onto the BBB - right? The interface between the Botic and the DAC is via i2s, which requires the shortest possible interconnects and no longer than 10cms - right? So the question that it is begged is, given the list of interferences listed by meiro, what is the optimal location for the BBB/Botic relative to the DAC/audio modules?
Oh, and I received into my possession today an Element14 BBB! Thanks Greg.
Ray
There will be ribbon cable connector on the cape, so somewhere close to this connector on the DAC.
Such cable was good enough for 16-bit IDE interface with max. length of 18 in (457 mm) and there were 16-133 MB/s data rates... so it should be good for I2S too
meiro, I don't believe it is that simple and understand the maximum length of cable for i2s before significant degradation is 10cm. Remember, i2s is actually intended for inter-chip connection on PCBs.
Ray
Maybe I'll add following I2S test to the next version of Botic demo image:
- two BBB will be required
- one configured for playback
- other one configured for record
- pseudo-random data generated and played to other BBB
- received and checked if matches transmitted data or not
EDIT: DSD variant of this test might be possible too...
- two BBB will be required
- one configured for playback
- other one configured for record
- pseudo-random data generated and played to other BBB
- received and checked if matches transmitted data or not
EDIT: DSD variant of this test might be possible too...
meiro, again, not that simple; I'm sure that doing something like checksum comparison will show that the bits arrive but timing (jitter) is the issue.
Ray
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.