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HSJIII
09-19-2014, 09:06 AM
I'm just getting started with reaper, and I REALLY bad experience: Apparently I managed to cook my DAC using reroute between FL and Reaper. I had no idea this was even possible, so it proved to be quite the rude awakening. I just placed a new order for a DAC, and meanwhile, the need for a line fuse is stalking me. Unfortunately, I have no idea what amp of fuse I would put into the line. Can anyone answer this question? The wire is carrying a signal is between the "line in" and "audio out" of two soundcards which are patched together at the back of a computer. What rating of fuse would you use for that? Also, can anyone recommend a fuse holder? I have some in mind, but someone here probably already knows something, so I'd like to hear what you think.
THANKS!
Sam

PS: I would be using 3.5mm stereo cable.

JHughes
09-19-2014, 10:58 AM
You should not need a fuse, and I've never seen such a thing.

If you did use one, it would be the smallest you can find, since the line out to line in is for signal (voltage) transfer, not current or power.

karbomusic
09-19-2014, 11:11 AM
You should not need a fuse, and I've never seen such a thing.

If you did use one, it would be the smallest you can find, since the line out to line in is for signal (voltage) transfer, not current or power.

@ Line level, I think it's called a limiter. :D

HSJIII
09-19-2014, 02:28 PM
You should not need a fuse, and I've never seen such a thing.

If you did use one, it would be the smallest you can find, since the line out to line in is for signal (voltage) transfer, not current or power.

Maybe I misunderstand the cause of hardware failure... but page 56 of the reaper manual specifies that too strong of a signal can damage equipment.
http://dl.reaper.fm/userguide/ReaperUserGuide472C.pdf

Maybe they are only talking about speakers...but they are vague.

What is the expected volts/amps of an audio signal? anyone know?

HSJIII
09-19-2014, 02:30 PM
@ Line level, I think it's called a limiter. :D

always a clown...lol... i had no way of expecting an interim route to matter too much. i was just trying to get it even working (with the endpoint volume really low).

karbomusic
09-19-2014, 03:13 PM
always a clown...lol... i had no way of expecting an interim route to matter too much. i was just trying to get it even working (with the endpoint volume really low).

Hehe, there was a smidge of technical truth in my joke though. I wouldn't expect that either but anything that is truly considered line level should not be a problem which is a around a volt give or take ~half a volt or more depending...

http://en.wikipedia.org/wiki/Line_level

However... What level are you running it out of FL or Reaper at? If you were pumping it out near zero dbFS that may be well more. For example, I just ran a 1k tone out of my sound card near 0dbFS and it was 3.6 Volts on the wire. That's also an interesting number to me because a number of op amps I use... that is close to their non-clip output ceiling. Try something closer to -10 or -15 instead. You can use your sound card specs and most likely calculate this but it's one reason I tend to shy away from 0dbFS signals when communicating with the outside world no matter who yells at me for doing so. ;) That's only assuming you were running that hot.

HSJIII
09-19-2014, 04:28 PM
Hehe, there was a smidge of technical truth in my joke though. I wouldn't expect that either but anything that is truly considered line level should not be a problem which is a around a volt give or take ~half a volt or more depending...

http://en.wikipedia.org/wiki/Line_level

However... What level are you running it out of FL or Reaper at? If you were pumping it out near zero dbFS that may be well more. For example, I just ran a 1k tone out of my sound card near 0dbFS and it was 3.6 Volts on the wire. That's also an interesting number to me because a number of op amps I use... that is close to their non-clip output ceiling. Try something closer to -10 or -15 instead. You can use your sound card specs and most likely calculate this but it's one reason I tend to shy away from 0dbFS signals when communicating with the outside world no matter who yells at me for doing so. ;) That's only assuming you were running that hot.

Well, the external dac was very warm to the touch, and it's inside a case... meaning something inside there did get hot... and it's only supposed to run a few watts, so to get any heat I could feel on the case means it was using alot more than a few watts.

It wasn't going through the line from FL in any controlled way. From reaper it was midrange. The out channel showed volume around half. So did the in channel. FL was sending what it thought was maxed out. Reaper was getting it back, noise reduced (with a volume slider). It might have formed an infinite loop with rearoute. The sample was very high bitrate... maybe that had something to do with it. Normally I wouldn't expect any of that to be an issue. I let it do that all the time when I'm working on stuff (until i get it under control, that is).

Did you happen to check the amps on your out line, too? It's Amps that make line heat, if I remember correctly. The wiki article only talks about volts.

BTW, I'm skeptical that it had to do with volume. I think it had to do with amps. Maybe the circuit closed a loop and the amps built up, somehow. I really don't know... not even sure what's possible, here. I just want a line fuse! lol

HSJIII
09-19-2014, 04:33 PM
You should not need a fuse, and I've never seen such a thing.

If you did use one, it would be the smallest you can find, since the line out to line in is for signal (voltage) transfer, not current or power.

One would think that, but again, the dac was only supposed to use 3.5 watts, and it was very warm to the touch. It takes more than 3.5 watts to do that. I think maybe something got bridged into a loop, and the amps built up... who knows.

JHughes
09-19-2014, 04:52 PM
I think the DAC just failed and you did nothing wrong.

HSJIII
09-19-2014, 05:03 PM
I think the DAC just failed and you did nothing wrong.

If it had happened during standard use, I would say you are probably right, but it was the first time I had connected rearoute that way... I was struggling to make it work... trying every weird thing (click here there etc)... to get a signal to the final endpoint. I think I just connected something which was terminal for the card...maybe.

karbomusic
09-19-2014, 05:35 PM
Did you happen to check the amps on your out line, too? It's Amps that make line heat, if I remember correctly. The wiki article only talks about volts.

If I continue to crank the volts, the light bulb in my flashlight will burn out due to Ohm's Law.

BTW, I'm skeptical that it had to do with volume.

Based on your latest replies I can't say it's volume either but something did go wrong and it died. Have you by chance researched this particular device to see if others have had the same issues?. Failures in mass produced devices tend to cluster together.

HSJIII
09-19-2014, 05:43 PM
If I continue to crank the volts, the light bulb in my flashlight will burn out due to Ohm's Law.



Based on your latest replies I can't say it's volume either but something did go wrong and it died. Have you by chance researched this particular device to see if others have had the same issues?. Failures in mass produced devices tend to cluster together.

No, I didn't. It's really an obscure dac. I ordered it from China. Hard to find much of anything about it. The website is even mostly in Chinese. I'm going with the assumption that it was somehow my own actions... the timing is too specific to pushing it to the boundaries with a new max ever bitrate, max ever sample rate, and also routing in a potentially circular way... reroute and patch wires... but I think rearoute is probably what put the final nail into its coffin. I know I'm in wild speculation territory, but I need some working hypotheses, and that feels like the lead contender to me...oriented on that cluster of facts.

Yes, voltage also has some effect on heat, but I think it's amps that really fry circuits. That's why they rate fuses in amps, rather than volts... and also why they run electricity through power lines at high volts rather than high amps. It's the amps that really get cooking. Volts are "gentler" for the line.

karbomusic
09-19-2014, 05:59 PM
Yes, voltage also has some effect on heat, but I think it's amps that really fry circuits

V=I*R, I=V/R... P(watts/heat)=I*V... if the resistance in a circuit remains constant, then voltage and current are directly proportional, so an increase in one will increase the other IIRC. However, the watts/heat created from that formula is what kills the circuit because it can't dissipate that heat fast enough before melting something. If you could remove heat fast enough, you could theoretically have an amplifier running at near zero ohms or in other words a very loud and great sounding oven. :D

Chinese or not, it's the build quality that matters. If the circuit is designed to "technically" meet the spec, that doesn't mean it can handle real world use or any unexpected conditions very well. It could be as simple as an overrated capacitor biting the dust as they are explicitly sensitive to volts or it could be a simple design flaw. I think the warmth is a clue but only knowing "something" was warm makes everything mostly speculation.

Did it utterly and completely die as in won't even display that it has power?

HSJIII
09-19-2014, 09:58 PM
V=I*R, I=V/R... P(watts/heat)=I*V... if the resistance in a circuit remains constant, then voltage and current are directly proportional, so an increase in one will increase the other IIRC. However, the watts/heat created from that formula is what kills the circuit because it can't dissipate that heat fast enough before melting something. If you could remove heat fast enough, you could theoretically have an amplifier running at near zero ohms or in other words a very loud and great sounding oven. :D

Chinese or not, it's the build quality that matters. If the circuit is designed to "technically" meet the spec, that doesn't mean it can handle real world use or any unexpected conditions very well. It could be as simple as an overrated capacitor biting the dust as they are explicitly sensitive to volts or it could be a simple design flaw. I think the warmth is a clue but only knowing "something" was warm makes everything mostly speculation.

Did it utterly and completely die as in won't even display that it has power?

No, it didn't die like that. Half the card is still responsive. It still triggers windows to notice something plugged in. Windows still knows what drivers to load. It still shows up on the ASIO4All list. You can still set things to use its resources... FL even "says" that it's sending audio _to_ the DAC, but no audio comes from its outputs.

Repetition Compulsion
09-20-2014, 12:17 AM
Open it up, look for something fried. If all that works and just audio out is messed up, then maybe you just fried a line somewhere in the output section. Could be as simple as a dab of solder to fix it up.

Keeping in mind this is coming from the guy who will tear open any electronic device at the slightest sign of issue, just for the sake of seeing the inside :P

HSJIII
09-20-2014, 02:04 PM
Open it up, look for something fried. If all that works and just audio out is messed up, then maybe you just fried a line somewhere in the output section. Could be as simple as a dab of solder to fix it up.

Keeping in mind this is coming from the guy who will tear open any electronic device at the slightest sign of issue, just for the sake of seeing the inside :P

The thought has crossed my mind, but I need a star screwdriver to open the case... and a part of me is still wondering if it will come back on its own, by some miracle.

If it continues to not work I might do what you say... the big inhibitor is an uncertainty over whether I bridge a circuit the wrong way. I don't want to cook my motherboard.

Repetition Compulsion
09-20-2014, 04:20 PM
Ah I thought it was an external unit. Still though, just opening it up (with power off!!) and lookin for signs if damage like burn marks or fucked up components won't hurt anything but it may give you answer and allow you decide whether to attempt repair or get on with replacement.

HSJIII
09-20-2014, 07:57 PM
Ah I thought it was an external unit. Still though, just opening it up (with power off!!) and lookin for signs if damage like burn marks or fucked up components won't hurt anything but it may give you answer and allow you decide whether to attempt repair or get on with replacement.

Well, it's the dac that has a case. In fact my PC does not. :-) I took that thing off when I overclocked, a couple years ago. I don't always run the PC OC'd, but when I do, it's without a case. :-D

So it's the DAC with a case, not the PC.

I might take it apart, but I'm torn between conflicting possibilities. I have a warranty card written only in chinese. I don't know wtf it says, or how to fill it out... but maybe I can convince someone to fill it out, and do a warranty exchange. I've had it for 2 years though.

Another possibility is that I introduced a device conflict which is smothering that card. It seems "possible" but less likely than the reroute having cooked it.

Well, anyhow, to open the dac I would need a star of david screwdriver. That gives me some time to think about what to do, b/c I don't have one.