[joneeboi]

Yeah, you can probably tell I'm out of the loop.

I get some free software from Microsoft through the Electrical Engineering department at the U of A because we're part of the MSDN Academic Alliance. I was thinking of getting the full version once I got back to school, but I realized that it doesn't even come out until October.

But alas, I installed the release candidate of Windows 7 32-bit. You're all probably annoyed of me bothering all the time, but the PCM still isn't working for me. u_u"" Hayduke, did you have to do anything more than plug and play?

 

[tomb]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif Yeah, you can probably tell I'm out of the loop. I get some free software from Microsoft through the Electrical Engineering department at the U of A because we're part of the MSDN Academic Alliance. I was thinking of getting the full version once I got back to school, but I realized that it doesn't even come out until October. But alas, I installed the release candidate of Windows 7 32-bit. You're all probably annoyed of me bothering all the time, but the PCM still isn't working for me. u_u"" Hayduke, did you have to do anything more than plug and play?

OK, this is getting a bit annoying with your PC.

I'm wondering if it's something in the hardware/motherboard at this point?

 

[lynxkcg]

I got mine up and running great. Had a little trouble with a flipped LED, then I assumed the whole board didn't work. Swapped in a new light, and realized it all worked. Flux pens are worth their weight in platinum. Listening to the improvement it's made is making my wallet nervous in fear of what's next.

 

[tomb]

Quote:

Originally Posted by lynxkcg /img/forum/go_quote.gif I got mine up and running great. Had a little trouble with a flipped LED, then I assumed the whole board didn't work. Swapped in a new light, and realized it all worked. Flux pens are worth their weight in platinum. Listening to the improvement it's made is making my wallet nervous in fear of what's next.

Glad to hear it! Yes, a flux pen works wonders with SMD soldering.

 

[joneeboi]

Okay, so I think this one solves the problem.

USB port may stop working after you remove or insert a USB device

I disabled "USB Selective Suspend" in my power management options, but checking the registry showed that it didn't...register(?). I manually disabled "Selective Suspend" in the registry and restarted the computer. It messed up once after listening for close to an hour, but I haven't been able to replicate the problem in the following half hour. The problem was that the music cut out, not that static was produced. I will do some more stress testing later on, but so far so good. Gross, is the PCM messing up on your laptop?

 

[Gross]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif Okay, so I think this one solves the problem. USB port may stop working after you remove or insert a USB device I disabled "USB Selective Suspend" in my power management options, but checking the registry showed that it didn't...register(?). I manually disabled "Selective Suspend" in the registry and restarted the computer. It messed up once after listening for close to an hour, but I haven't been able to replicate the problem in the following half hour. The problem was that the music cut out, not that static was produced. I will do some more stress testing later on, but so far so good. Gross, is the PCM messing up on your laptop?

Laptop works great, actually, I used my Carrie for about 5 hours off of my laptop in the work van today. Very happy with it.

My issue is with one of my PCs at home. Like you, I also uppped it to Windows 7, 64 bit, and regrettably I still have the issue. I did a clean install, so I would have to say it is a hardware type thing. I checked in the bios for any sort of USB settings (legacy, power, etc) and at this point have not been able to resolve it. When using it the left and right tend to jump around and then eventually I just get static. I tried multiple ports on the machine hoping maybe it was just 1 usb host controller, but no such luck.

I would be curious if I used a different USB controller card (PCI or whatever) but I don't have one sitting around to try. I havn't spent a whole lot of time working on it since now I have just been bringing my laptop to my other PC when I want music. I know, I know. Sad and lazy

 

[Hayduke]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif I installed the release candidate of Windows 7 32-bit. You're all probably annoyed of me bothering all the time, but the PCM still isn't working for me. u_u"" Hayduke, did you have to do anything more than plug and play?

I didn't do anything other then plug it in on either box. The 64 bit build 7100 (RC1) is at work. Here at home, I have a 32 bit build 7077 and the Bantams work fine. I only have one working right now and I'm listening to it on my 32 bit Windows 7 right now (The Cranberries are pretty great hehe).

I never had any problems with the 64 bit Windows 7 either, but I haven't been using a Bantam there since my MHSS killed one a few weeks ago

I'm planning to rebuild it, but I've been way to busy lately.

 

[joneeboi]

Quote:

Originally Posted by Gross /img/forum/go_quote.gif Laptop works great, actually, I used my Carrie for about 5 hours off of my laptop in the work van today. Very happy with it. My issue is with one of my PCs at home. Like you, I also uppped it to Windows 7, 64 bit, and regrettably I still have the issue. I did a clean install, so I would have to say it is a hardware type thing. I checked in the bios for any sort of USB settings (legacy, power, etc) and at this point have not been able to resolve it. When using it the left and right tend to jump around and then eventually I just get static. I tried multiple ports on the machine hoping maybe it was just 1 usb host controller, but no such luck. I would be curious if I used a different USB controller card (PCI or whatever) but I don't have one sitting around to try. I havn't spent a whole lot of time working on it since now I have just been bringing my laptop to my other PC when I want music. I know, I know. Sad and lazy

I know, I'm really enjoying it on my XP desktop at work.

Alas, I've changed the USBAUDIO.sys driver from the 2009 edition to the XP usbaudio.sys as described here.

replacing sys file in vista! - Nightmare! - Icrontic Forums

Switching USB ports doesn't help. All USB Root Hubs have the most recent drivers. It messes up when my computer is plugged in and when it runs on batteries. I even changed the usbaudio registry "Start" entry from 3 to 2, meaning it will always be on, even if no USB speaker is plugged in.

Quote:

Originally Posted by Hayduke /img/forum/go_quote.gif I didn't do anything other then plug it in on either box. The 64 bit build 7100 (RC1) is at work. Here at home, I have a 32 bit build 7077 and the Bantams work fine. I only have one working right now and I'm listening to it on my 32 bit Windows 7 right now (The Cranberries are pretty great hehe). I never had any problems with the 64 bit Windows 7 either, but I haven't been using a Bantam there since my MHSS killed one a few weeks ago I'm planning to rebuild it, but I've been way to busy lately.

I checked voltages on all the chips while the static went nuts, and everything checked out. None of the chips were overheating, so it doesn't seem to be a hardware issue on the DAC/amp side. Installing Vista SP2 didn't work, and using Windows 7, either by upgrading (me) or by clean installing (Gross), didn't work. It doesn't work on my laptop 32-bit, and it doesn't on Gross' desktop 64-bit. It works on Hayduke's Windows 7s, both in 32- and 64-bit.

Here are some links that I've read in the past week:

Why aren't my USB speakers working correctly?
Laptop USB ports stopped working - CNET Windows XP Forums
USB port may stop working after you remove or insert a USB device
Some USB audio devices and some USB audio TV tuners do not work correctly together with a Windows Vista-based computer
USB devices may not work after your Toshiba notebook computer returns from standby in Windows XP
http://www.henleydesigns.co.uk/asset...elpNotesv2.doc
A hotfix rollup for the USB audio driver is available for Windows Vista-based and Windows Server 2008-based computers
An Audio Streaming Input and Output (ASIO) driver may not work correctly on a Windows Vista-based computer
The audio from a USB speaker is distorted after you connect an additional USB device to a Windows Vista-based computer
Cumulative update rollup for Windows Vista

I will try reinstalling my USB controllers, though I imagine them to be working just fine. Such is life when troubleshooting...

 

[Hayduke]

I can't recall which USB device it was (It wasn't my Bantam), but I recall having a problematic device and I had to uninstall all the USB devices in device manager and then reboot and let Windows rebuild them all. Of course, this was back when my home machine was XP, but it did solve the issue.

Sorry I can't be of much more help, but I've had zero problems with my Bantams on Windows 7.

 

[joneeboi]

Actually, the route I took was to downgrade from 7 to XP. It's taken 8 days, but I finally did it. I've never done anything so grueling in a while. First, I couldn't boot from the XP CD because my hardware required an XP SP2 build. Then I didn't have any CDs to burn, so I tried booting via USB. That didn't work out for some reason. Then my SATA HDD was set in the wrong mode in the BIOS, so that took me a while to figure out. And then my Windows XP product key didn't work. After waiting a long time on the phone and getting shuffled around from line to line, I got a new product key and now I'm setting up my new computer. Hurrah.

Yes, I'm probably the worst case scenario when it comes to the PCM2702.

I'm getting there, little by little. At least I have a little more control over my more reliable OS now.

 

[TheEKey]

Hello Guys,

It happened that IC2 of my Bantam DAC was fried sometime ago.

Call it DAC 1, using Elna RFS Silmic II as output caps.

There's DAC 2, Wima as output caps.

First I found that there were serious distortion from the music that I play from my PC. So I disconnected it and reconnected it again. It gave much noise to the loudest volume (so even I turned down the winamp vol to 0, noise was not affected at all). So I disconnect it and reconnect it again. It went totally off (reading only 0.7V instead of 4.7V on IC2).

IC2 on DAC1 fried.

But I applied the same sequence to DAC2. No problem so far.

I'm not sure what happened. I suspect that it's how I connect/disconnect the DAC to the amp and computer. Does it make any sense?

Connecting: I usually turn on and warm up the AMP, Millett Hybrid MAXed. Meanwhile, connect the DAC to the computer. After about ten minutes, connect the input of amp to the output of DAC. Then, I plug in the headphone and start enjoy music.

Disconnecting: Stop music -> Turn vol of amp to 0 -> unplug the headphone -> power off the amp -> disconnect it from the DAC and unplug the DAC.

Any of these sequence can potentially cause the IC2 to be fired? Please advise.


Best regards,

Matt

 

[tomb]

Quote:

Originally Posted by TheEKey /img/forum/go_quote.gif Hello Guys, It happened that IC2 of my Bantam DAC was fried sometime ago. Call it DAC 1, using Elna RFS Silmic II as output caps. There's DAC 2, Wima as output caps. First I found that there were serious distortion from the music that I play from my PC. So I disconnected it and reconnected it again. It gave much noise to the loudest volume (so even I turned down the winamp vol to 0, noise was not affected at all). So I disconnect it and reconnect it again. It went totally off (reading only 0.7V instead of 4.7V on IC2). IC2 on DAC1 fried. But I applied the same sequence to DAC2. No problem so far. I'm not sure what happened. I suspect that it's how I connect/disconnect the DAC to the amp and computer. Does it make any sense? Connecting: I usually turn on and warm up the AMP, Millett Hybrid MAXed. Meanwhile, connect the DAC to the computer. After about ten minutes, connect the input of amp to the output of DAC. Then, I plug in the headphone and start enjoy music. Disconnecting: Stop music -> Turn vol of amp to 0 -> unplug the headphone -> power off the amp -> disconnect it from the DAC and unplug the DAC. Any of these sequence can potentially cause the IC2 to be fired? Please advise. Best regards, Matt

No.

The only known instance of frying Alien DACs and BantamDACs is with the Starving Student. That amp has a peculiar power arrangement and the MOSFETs are biased through the tube heaters to ground. The best we've been able to determine lately is that a capacitive charge may develop on the RCA jacks that fries the DAC. Even then, it's the DAC that's fried - because it has no inherent protection on the analog outputs. On any other amp, however, the output capacitors are sufficient for protection.

I have connected/disconnected Alien and BantamDACs in almost every way imagineable - everything from prototype boards, MAXes, MOSFET MAXes, and MiniMAXes - prototypes and production models, using PC's, Laptops, Netbooks, USB hubs, USB cable repeaters, etc., etc. and in all environments - home, work, and headphone meets. Never once have I had an incident with any MAX/MiniMAX/MOSFET-MAX.

The fact that you're saying IC2 was fried leads me to suspect it was probably hanging by a thread at the start. I am not aware of any connection/disconnection scenario even with the Starving Student that would fry IC2. While any device such as IC2 is susceptible to ESD, it shouldn't be once attached to the board and properly grounded. It also has output current limiting as a safety feature.

IMHO, your connections/disconnections had nothing to do with it.

 

[joneeboi]

Since this is a thread for commenting on the board's layout, I think the VREG caps should be rearranged such that ground and line aren't so close. By now, a good few hundred Bantams have been built without a problem, but I see this as a potential hazard. I think we're mostly fine with the TPS chips limiting output current, but they can generate quite a bit of thermal energy when shorted. It's fairly easy to bridge these pads, so I think it would be safer to flip the caps a bit. This observation applies to C14, C15 and IC2's TPS C16. Again, the world will spin even if these caps stay put, but that's my comment on the layout.

 

[tomb]

Quote:

Originally Posted by joneeboi /img/forum/go_quote.gif Since this is a thread for commenting on the board's layout, <snip>

Actually, this is the BantamDAC thread. It's just that "Comments for my PCM2702 Layout" was back in August of 2006 and Colin can't edit that title anymore because it's so old.

 

[Rooford]

Hi,

I've built two BantamDACs and have to say I'm really pleased with them. To my ears it takes 10 hours or so for the output capacitors to really break in.

I thought I'd add a couple of notes for anybody using Ubuntu/Amarok/Alsa drivers as I don't think it's been covered in this thread.

First off open a terminal and check the DAC is listed as a usb device:
$lsusb

You should see the DAC listed along with other USB devices.

Then check the sound card is available using the asound utility:
asoundconf list
Names of available sound cards:
Intel
PCM2702

I then set the DAC to be the default:
asoundconf set-default-card PCM2702

This will create a file in your home directory:
.asoundrc

You can then using Amarok as your media player, index and play your music collection. Use Google to find help on setting up Amarok to play mp3s.

This works fine however, I noticed that the alsa driver uses dmix to upsample the output to 48KHz.

Use the following command while playing an mp3 file to check. Note: The PCM2702 sound card is listed as card1 for me.

cat /proc/asound/card1/stream0

access: MMAP_INTERLEAVED
format: S16_LE
subformat: STD
channels: 2
rate: 48000 (48000/1)
period_size: 1024
buffer_size: 16384

You can see a list of supported sample rates for the device using:

cat /proc/asound/card1/pcm0p/sub0/hw_params


While upsampling is OK if you'd prefer the alsa driver to leave the sample rate alone you can tweak your ~/.asoundrc file to setup an alsa plugin. You'll need to know how alsa identifies the DAC, use aplay:

aplay -l

As mentioned before my DAC shows up as card 1 device 0. Infact the DAC should only have one device.

Then edit your ~/.asoundrc file:
pcm.myCard {
type hw
card 1
device 0
}
ctl.myCard {
type hw
card 1
device 0
}
pcm_slave.s44100 {
pcm myCard
rate 44100
}
pcm.rate_convert {
type rate
slave s44100
}


It's a bit esoteric but you're creating an alsa software slave plugin for your hardware card. Save the file then restart your alsa service:
sudo /etc/init.d/alsa-utils restart

Then restart Amarok (make sure it doesn't just hide in the system tray).

In Amarok settings->Engine->Output Plugin
Change to alsa rather than default

Click apply, some options should appear for Mono / Stereo playback.

Change the Stereo option to:
plug:rate_convert

Note: I found in the alsa notes that the alsa driver will by default try and use the same sample rate if the card supports it so you could also change the stereo option to:
plug:myCard

Then check the sample rate is now 44.1KHz using
cat /proc/asound/card1/stream0


Hopefully that helps!

BTW, the DAC works fine on Mac OSX, you can change the default sample rate using the Audio Midi Tool in /Applications/Utilities
Click the Audio Tab and choose Burr-Brown Japan PCM2702 to set the default output device. You can also tweak the sample rate there although it defaults to 44.1KHz