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Can Anybody Assist With my Optical Issue?

dmusgr

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Long, long time lurker, first time poster with a possibly dumb question.

I'm a headphone guy to get that out of the way.

I decided to throw together a 2 channel setup for music and movies. Here is the problem I'm having...

Optical out of my TV into my Topping DX3 Pro+ works, but it is "scratchy for a second " every 3 or 4 seconds. I mean it sounds like the "'scratchy" audio is on a timer, it happens 3 or 4 seconds apart, or about a half a second, with perfect consistency. The Topping is feeding an older Rotel 1056 that I bought new old stock, brand new in box for 104.00 (score IMO!) via RCA cables. I have changed the output from the TV to PCM, and the Topping sees the signal as PCM.

I'd prefer to go through the Topping DAC rather than the older DAC in the Rotel, but just to see what happened I tried that and I got exactly the same thing with the Topping bypassed. Exactly the same thing.

I'm not "fully" set up, so I tried streaming Tidal via BT to the topping and everything worked smashingly. Not optimal, as I think BT is lossy/compressed right? But it worked perfectly. So I sent sound out of my TV via BT into the Topping and it too worked smashingly, but again I don't think optimally, as it's lossy/compressed right?

My TV looks great and it's huge, but it's not a "top of the line" model. I expected an option to tell it to send audio out of the Optical, but there isn't one. It does seem to autodetect Optical and switch to it when plugged in though. And there is an option to change audio to PCM, and like I said, I have.

Do I have a bad Optical Cable? I don't have anything else to try it on unfortunately. I'm going to purchase a new one once Best Buy opens, but if that doesn't resolve my issue, is this something with my TV that I simply might not be able to fix? Do I have to live with everything coming out of my TV going to the Topping via BT? A computer will be hooked up to the Topping via USB to stream Tidal and Qobuz for music, and eventually I'd like to add a turntable. I should also be able to play CDs from my BluRay player, but that has to route through the TV than to the Topping due to limited options on my new but lower end TV and my "older" Rotel.

I have not torn my headphone rig apart and tried it in the living room feeding the Rotel yet... maybe I should try that? I can also feed optical from the TV to it, and that would rule out something with the Topping? But I've bypassed the Topping already and had the same issue...

So long story short, everything works other than optical from the TV into either the Topping or bypassing that DAC and using the Rotel with it's older DAC. Both exhibit the same problem.

Thanks for any help you guys can offer!

Dave
 

ZolaIII

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Optical implement on that Topping is broken.
 
OP
dmusgr

dmusgr

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Optical implement on that Topping is broken.
Well that isn't cool! I can't believe I didn't see anything regarding that before I bought it, I'm a big researcher. Nobody to blame but myself. I've had it for months and just opened it. I don't know if I'll put my DO400 in the living room and see if it works properly, or just go straight into the older DAC in the Rotel from the TV and just use the USB on the Topping from a PC for my Tidal and Qobuz. I'm sure the issue I'm having there is a setting in the Rotel itself, and I don't have the AAA batteries to get into the menu to change anything. Pretty sure I have to tell it that the optical input is feeding a specific input, as there is no button to choose optical. I kinda like my SMSL with my headphones in the other room. Thanks for the quick answer my friend. Off to the store for AAA batteries a, a different optical cable (obviously not going to fix the Topping issue so I might as well not bother, it'll get returned unopened) and come back home and try to get this thing going!
 
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dmusgr

dmusgr

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Gotta say the BT thing is kinda cool though, if anybody comes over and wants to listen casually, they can just BT to the device and play their own playlists, etc. First time I've ever really messed with it other than in my car, and it was super convenient to make sure everything actually worked as it should other than the optical! I don't know anybody that cares if it's FLAC or MP3 over BT even if they can hear the difference sadly.
 

audio_tony

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Optical out of my TV into my Topping DX3 Pro+ works, but it is "scratchy for a second " every 3 or 4 seconds. I mean it sounds like the "'scratchy" audio is on a timer, it happens 3 or 4 seconds apart, or about a half a second, with perfect consistency. The Topping is feeding an older Rotel 1056 that I bought new old stock, brand new in box for 104.00 (score IMO!) via RCA cables. I have changed the output from the TV to PCM, and the Topping sees the signal as PCM.

I'd prefer to go through the Topping DAC rather than the older DAC in the Rotel, but just to see what happened I tried that and I got exactly the same thing with the Topping bypassed. Exactly the same thing.
So the Rotel does it, even when fed directly leaving the Topping out of the path?

That rules out the Topping and optical cable then, and any fault must lay with the Rotel surely?

It could well be that the 'old stock, brand new in box' Rotel was a return that was faulty.
 

staticV3

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Common issue with LG TVs where the digital outputs are poor and lead to stutter, dropouts etc with many DACs.

@dmusgr look for a DAC with configurable DPLL. a DX3Pro+ equivalent would be the SMSL C200 or DL200.

By increasing the DPLL in the menu, you should be able to restore stable playback.
 

radix

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There are $20 - $100 HDMI to TOSLINK extractors, so maybe you could use one?

I'm not sure how specific ones measure.
 

Blumlein 88

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Optical implement on that Topping is broken.
Reading that thread I wouldn't totally blame the Topping. Partly. Apparently they like a lower jitter input which some TVs aren't so good at providing. Since many other DACs manage to work anyway, then maybe Topping has part blame. In any case, the Op apparently has a combo in the Topping and TV that are having that problem.
 

ZolaIII

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@dmusgr to save you a lot of reading it's not switching from AKM to other DAC's or Topping as Topping it's that they run out of Toshiba original Toslink parts and started using what they could get and it didn't turn out good (nor it will). I am downgrading my own setup (a bit) right now switching from Creative AE-5 to Z SE for Toslink I/O.
What's the DAC in old Rotel? Old uper range BurrBrown's were great and had a lot of design wins in their time. Any 100 dB SINAD DAC will be more than transparent to feed speakers. Having a Toslink I/O has becoming hard to find and that's why I am downgrading (so I can apply full DSP tool chain on Toslink input).
 
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dmusgr

dmusgr

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I've got everything but optical pretty much dialed. I don't have anything else to test with, so it's either going to be BT or HDMI to optical from the TV to see if that works. I'm assuming the optical out on my TV is junk at this point. Real glass optic made no difference over cheap plastic optic. You guys are awesome!
 
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dmusgr

dmusgr

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Common issue with LG TVs where the digital outputs are poor and lead to stutter, dropouts etc with many DACs.

@dmusgr look for a DAC with configurable DPLL. a DX3Pro+ equivalent would be the SMSL C200 or DL200.

By increasing the DPLL in the menu, you should be able to restore stable playback.
I've got a DO400 but I really, really want to keep it in my bedroom for headphone use.
 

MaxwellsEq

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As others have said, the TV is the problem, and most modern TVs are equally bad. Not only do they deliver terrible jitter, but they don't properly deploy the S/PDIF protocol, putting erroneous data in. However, the popular AK receiver chip ignored the nonsense and did a good job with the jitter. Then there was the AK fire and designers has to use receiver chips which (quite rightly) were unhappy with the nonsense, and did not handle the serious jitter problems unless a PLL was deployed that could be user adjusted to "ride out" the choppy seas.
 

ZolaIII

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It's reciver decoder chip. AKM, CS and BurrBrown (now Ti) are synchronous the ES is asynchronous and has foal back protection when jitter and noise suddenly increases that switches of input until conditions improve. Not only LG but also Samsung TV's were affected meaning bad implementation from their side. Japanese where not.
It's not DAC chip fault.
 

MaxwellsEq

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It's not DAC chip fault
I agree it's not the DAC chip. It's bad S/PDIF output from TVs and current receiver chips being less tolerant than AK's.
 

ZolaIII

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I agree it's not the DAC chip. It's bad S/PDIF output from TVs and current receiver chips being less tolerant than AK's.
ES S/PDIF input chip can be switched to legacy synchronous mode or relaxed asynchronous but it needs to be done in firmware update.
 
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dmusgr

dmusgr

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So I ordered a powered box that is supposed to convert HDMI to Optical, and it doesn't work on either my DAC or AVR. I think everybody is correct, the TV is at fault. I'll just live with using BT for a while from the TV to the DAC, it seems to work fine. I'm not listening to music from the TV anyway.
 

staticV3

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So I ordered a powered box that is supposed to convert HDMI to Optical, and it doesn't work on either my DAC or AVR. I think everybody is correct, the TV is at fault. I'll just live with using BT for a while from the TV to the DAC, it seems to work fine. I'm not listening to music from the TV anyway.
which box and how is it connected to the rest of your system?
 
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dmusgr

dmusgr

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It's just connected HDMI to the box above, and optical is connected to the other side of the box. I've tried into my DAC and my AVR.
 

staticV3

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It's just connected HDMI to the box above, and optical is connected to the other side of the box. I've tried into my DAC and my AVR.
where does the HDMI cable connect to on the other end?
 
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