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Connecting a S.M.S.L SU-1 DAC to a Pioneer VSX-935 Receiver

Remomoreira

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I bought and received yesterday a S.M.S.L SU-1 DAC, but I can't get it to work in my setup, between a Sony BDP-S6500 Blu Ray Player and a Pioneer VSX-935 Receiver. As the DAC only has one type of output, analog, it must be connected to the receiver's analog input (RCA). The Blu Ray player, in turn, is connected to the DAC via digital input (coaxial cable).

What happens is that the receiver simply does not recognize the DAC; In fact, it does not recognize any device connected other than via HDMI. Just last week I tried to make this same blu ray player work by connecting it to this receiver via digital input (coaxial cable), but the receiver didn't recognize it, which makes me believe that the problem is with it, that it isn't recognizing any connected device other than via HDMI.

I made all the possible settings on the three devices, and I don't know what else to do.
 

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Are you selecting the different inputs? Have you tried connecting the rca from the dac to all the rca input other than phono?
 
Does the blu ray player have analogue output? If so plug it into an RCA line in on the receiver.

The blu ray player needs to be set to PCM not bitstream to work with a DAC
 
I assume you know how to operate your devices, anyway:
  • BD player digital audio out has to be set as PCM in it's menu as @MaxwellsEq stated
  • rca of the SU-1 have to be connected to one of the 4 audio in of the Pioneer (not the Phono obviously) as @Jimbob54 stated
  • The input selector of the Pioneer has to be triggered since it shows the input you connected the SU-1 on the display
If you can't hear anything then much likely there is a problem with the input section of the Pioneer.

Do you have any other device you can connect to analog inputs of the Pioneer, even a Smartphone via an 3.5 mm to RCA cable?
 
Does the blu ray player have analogue output? If so plug it into an RCA line in on the receiver.

The blu ray player needs to be set to PCM not bitstream to work with a DAC
The blu ray doesnt have analogue output, only digital (coaxial) and HDMI. I have already set it to PCM.
 
The blu ray doesnt have analogue output, only digital (coaxial) and HDMI. I have already set it to PCM.
Does the blu ray player have analogue output? If so plug it into an RCA line in on the receiver.

The blu ray player needs to be set to PCM not bitstream to work with a DAC
The blu ray doesnt have analogue output, only digital (coaxial) and HDMI. I have already set it to PCM.
 
I assume you know how to operate your devices, anyway:
  • BD player digital audio out has to be set as PCM in it's menu as @MaxwellsEq stated
  • rca of the SU-1 have to be connected to one of the 4 audio in of the Pioneer (not the Phono obviously) as @Jimbob54 stated
  • The input selector of the Pioneer has to be triggered since it shows the input you connected the SU-1 on the display
If you can't hear anything then much likely there is a problem with the input section of the Pioneer.

Do you have any other device you can connect to analog inputs of the Pioneer, even a Smartphone via an 3.5 mm to RCA cable?
It worked! Thanks a lot! :)
 
What exhactly worked? From your previous answers seemed you already did everyrhing without success, so if you can elaborate.
Anyway glad it helped.
I had forgotten to connect the TV to the blu ray player through a HDMI cable; as soon as I did it, it worked!

However, I didn't notice any increase in audio quality. I did several tests here playing the same song on the Blu-ray player WITH and WITHOUT the DAC, and there was no noticeable difference in audio quality, at least to my ears.

I suppose the reason for this must be that the audio quality of my blu ray player's internal DAC is the same as that of the external DAC.
 
I had forgotten to connect the TV to the blu ray player through a HDMI cable; as soon as I did it, it worked!

However, I didn't notice any increase in audio quality. I did several tests here playing the same song on the Blu-ray player WITH and WITHOUT the DAC, and there was no noticeable difference in audio quality, at least to my ears.

I suppose the reason for this must be that the audio quality of my blu ray player's internal DAC is the same as that of the external DAC.

A few points:

1. DACs are a solved problem and have been for at least a decade. There is virtually no audible difference between most properly implemented DACs.
2. In most receivers, analog input is converted to digital, where bass management and/or room correction / EQ is applied. That means you are adding extra ADC and DAC steps to your signal chain by using an external DAC.
3. You are hearing the DAC in your AVR according to your previous post stating the Bluray player only has digital outputs (HDMI and coax)
 
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1. DACs are a solved problem and have been for at least a decade. There is virtually no audible difference between most properly implemented DACs.

Except in the case of most Windows PCs being sold today. Even some of the most expensive gaming laptops you can buy the DAC implementation is such a cheap afterthought that you can literally hear the difference in a blind a/b test after volume equalization at the listening point. Macs don't suffer from this - post-Ipod, Apple seems to have been able to put inexpensive but good DAC stages in basically every device they sell.

IIRC our host Amir once fought this battle with PC manufacturers in a previous job, tried to get the on-board sound standards upped a tiny bit on some implementation and he was shot down. There's an industry mindset: any buying customer who cares about good audio will be sending their signal out digital via USB anyway, don't bother spending anything on the DAC stage, just market it like you do.

(Also, I can hear a difference between the SMSL SU-1 and the on-board DAC in the WiiM Mini after volume matching, going out to Triangle Borea. YMMV.)
 
Except in the case of most Windows PCs being sold today. Even some of the most expensive gaming laptops you can buy the DAC implementation is such a cheap afterthought that you can literally hear the difference in a blind a/b test after volume equalization at the listening point. Macs don't suffer from this - post-Ipod, Apple seems to have been able to put inexpensive but good DAC stages in basically every device they sell.

IIRC our host Amir once fought this battle with PC manufacturers in a previous job, tried to get the on-board sound standards upped a tiny bit on some implementation and he was shot down. There's an industry mindset: any buying customer who cares about good audio will be sending their signal out digital via USB anyway, don't bother spending anything on the DAC stage, just market it like you do.

(Also, I can hear a difference between the SMSL SU-1 and the on-board DAC in the WiiM Mini after volume matching, going out to Triangle Borea. YMMV.)

Pretty random and barely on topic...

While I agree there is some truth to your assertion about PCs, I have also read the results of more than one properly conducted blind test that showed the participants all failed to differentiate a Realtek or similar motherboard DAC from an objectively SOTA external DAC.

(I am sure you think you can. I thought I could too until I failed every proper blind test I took. You need to VOLTAGE match the DACs, not volume match them.)
 
While I agree there is some truth to your assertion about PCs, I have also read the results of more than one properly conducted blind test that showed the participants all failed to differentiate a Realtek or similar motherboard DAC from an objectively SOTA external DAC.
I know, the Tom's Hardware test, I refer to and link to it often.

"There is no difference in modern DAC implementations" fails completely at the PC level, especially the laptop level. Hit and Miss doesn't begin to describe it. Laptop manufacturers build an inexpensive-to-build spec unit, and then they make a pass over every component to see if they can replace it in bulk with a cheaper manufacturer for that part. And then sometimes they do it again, a 2nd pass. The goal is to maximize that profit by sourcing the cheapest components while still remaining 'in spec,' and that means the on-board DAC chip gets no support of any kind and is often a noise magnet. If you get one that's not terrible, great, they maybe spent an extra $4.38 per unit on that build.

The reason this is completely on-topic is that many people - a growing number - stream Spotify, etc from their computers to .. something. If they're under the impression that a 28-cent on-board DAC implementation marketed as "surround sound!" is going to be good enough in every case, they're going to disappointed half the time. Right now my 16 year old is using a gaming rig we bought for something over $1K, and it's analog out is absolutely horrendous, at any volume. It's headphone amp isn't much better. Thank God for inexpensive external DACs.
 
I know, the Tom's Hardware test, I refer to and link to it often.

"There is no difference in modern DAC implementations" fails completely at the PC level, especially the laptop level. Hit and Miss doesn't begin to describe it. Laptop manufacturers build an inexpensive-to-build spec unit, and then they make a pass over every component to see if they can replace it in bulk with a cheaper manufacturer for that part. And then sometimes they do it again, a 2nd pass. The goal is to maximize that profit by sourcing the cheapest components while still remaining 'in spec,' and that means the on-board DAC chip gets no support of any kind and is often a noise magnet. If you get one that's not terrible, great, they maybe spent an extra $4.38 per unit on that build.

The reason this is completely on-topic is that many people - a growing number - stream Spotify, etc from their computers to .. something. If they're under the impression that a 28-cent on-board DAC implementation marketed as "surround sound!" is going to be good enough in every case, they're going to disappointed half the time. Right now my 16 year old is using a gaming rig we bought for something over $1K, and it's analog out is absolutely horrendous, at any volume. It's headphone amp isn't much better. Thank God for inexpensive external DACs.

That is one of them. There are several others.

PC DACs are relevant to a thread about placing an external DAC between a Bluray player and an AVR? Hardly.
 
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