Good RCA to Toslink converter?

[K man]

Is there any good, or at least reasonable, RCA to Toslink converter out there for less than €100?

This one seems to be found a bit of everywhere, but I wouldn't call -15db @ 20Hz reasonable...

The Swissonic AD seemed reasonable, would probably have been enough for my needs, but it's nowhere to be found any longer.

Is there any such converter out there, that doesn't either kill all the low frequencies or my wallet?

 

[Blumlein 88]

This is a surprisingly difficult product to find. I hope someone comes up with one for you. I've had a few uses for them.

 

[Berwhale]

The Swissonic HAD-1 maybe...

Swissonic HAD-1

Detailed Product Information on Swissonic HAD-1 at www.thomann.de

www.thomann.co.uk

It's an AD/DA and is slightly over budget, but might be worth a look.

 

[jordheis]

Blustream ADC11AU Analogue to Digital Audio Converter (ADC)
64 euro. Not sure it performs good enough based on the posted comments, but it has a 5 year warranty from this supplier fwiw.
That HAD-1 seems the better choice.

 

[bachatero]

This might sound weird, but I may be able to make one with actually good performance for you. Don't hold your breath though because I am waiting on a reflow oven and several other R&D tools.

 

[K man]

The Swissonic HAD-1 maybe...

Swissonic HAD-1

Detailed Product Information on Swissonic HAD-1 at www.thomann.de

www.thomann.co.uk

It's an AD/DA and is slightly over budget, but might be worth a look.

There is a confusing text printed on it saying "Optical output for USB only" and then USB In and S/PDIF Out are grouped together. I would understand this as if it only gives S/PDIF Out from USB In. However, in the manual it says:
"1. Connect an analogue signal source whose signals you want to digitize and / or listen to via headphones to the Line IN jacks (11).
2. Connect the S/PDIF Out socket (7) or the USB port (8) to the digital inputs of the devices to which the signals are to be applied."

This also contradicts the USB In statement on the device.

Quite confusing and I'm not sure what they intended with the print on the device, if the manual is correct...

Besides that the specifications on it does look good (enough).

 

[K man]

Blustream ADC11AU Analogue to Digital Audio Converter (ADC)
64 euro. Not sure it performs good enough based on the posted comments, but it has a 5 year warranty from this supplier fwiw.

That seems to be the very same device that was reviewed as unbranded. It keeps appearing a bit of everywhere, under a variety of different brands and price tags...

 

[K man]

This might sound weird, but I may be able to make one with actually good performance for you. Don't hold your breath though because I am waiting on a reflow oven and several other R&D tools.

Now, that's interesting.

I've sent you a PM.

 

[K man]

This is the best I've been able to find myself so far:
WONDOM AA-AS41115 ADC

The limited specs available seems ok, but the reviews are complaining about some background noise. There is also no info available on the frequency response in the lower frequencies.

 

[diablo]

I sometimes have a need to connect the RCA output from an AVR to my main setup. I have used various converters but as I now have a Wiim Pro I use the RCA inputs on that to get a Toslink input to my Minidsp. The specs are quite good, though the Wiim Pro Plus is better - though more expensive obviously.

It may seem overkill, but if you happen to find some of the other Wiim features of use then it may be a good solution.

 

[K man]

I sometimes have a need to connect the RCA output from an AVR to my main setup. I have used various converters but as I now have a Wiim Pro I use the RCA inputs on that to get a Toslink input to my Minidsp. The specs are quite good, though the Wiim Pro Plus is better - though more expensive obviously.

That’s not a bad idea. Although I would go with Wiim Mini, which is half the price, still with good specs and can indeed be found below €100.

Which again speaks for the price inefficiency in this market, when you need to buy a fully featured streamer to get the price down on some simple feature of it…

 

[MCH]

This is a surprisingly difficult product to find. I hope someone comes up with one for you. I've had a few uses for them.

Even worse if you need balanced input. You might end up having to spend your afternoon soldering your own, like me yesterday

 

[diablo]

That’s not a bad idea. Although I would go with Wiim Mini, which is half the price, still with good specs and can indeed be found below €100.

Which again speaks for the price inefficiency in this market, when you need to buy a fully featured streamer to get the price down on some simple feature of it…

I noted your earlier comment about bass drop-off in one converter. So, as I have a Wiim Mini, and the fireworks hadn't started yet, I tested sending the signal through that from RCA output from my D10S DAC and comparing it to the direct Toslink output from the D10S.

The output is from speakers/microphone obviously, so not meant to be dead flat.

The volumes are 1dB apart for clarity. There is a drop-off of about a third of a decibel.

 

[K man]

I noted your earlier comment about bass drop-off in one converter. So, as I have a Wiim Mini, and the fireworks hadn't started yet, I tested sending the signal through that from RCA output from my D10S DAC and comparing it to the direct Toslink output from the D10S.

The output is from speakers/microphone obviously, so not meant to be dead flat.

View attachment 417681
The volumes are 1dB apart for clarity. There is a drop-off of about a third of a decibel.

Nice!

That does make the Wiim Mini a good candidate.

I just which there was some more details to be found about the WONDOM AA-AS41115. From the few specs available it’s not far behind the Wiim Mini, but half the price. But, then again, it has no frequency response information at all.

 

[Roland68]

Audiophonics has a fully assembled and functional module with the PCM1804.
You could put it in a suitable housing or shrink tubing.
ADC Board Analog Digital Converter PCM1804 RCA to SPDIF 24bit 192kHz

 

[K man]

Audiophonics has a fully assembled and functional module with the PCM1804.
You could put it in a suitable housing or shrink tubing.
ADC Board Analog Digital Converter PCM1804 RCA to SPDIF 24bit 192kHz

Oh, that’s an interesting one!

That might be the best option so far, but there is one thing that isn’t clear; The PCM1804 chip has differential input, but the Audiophonics’ board has no information on whenever it has unbalanced, that’s converted to differential, or differential input.

In my experience it makes a major difference. I’ve struggled with unbalanced RCA to differential RCA before.

 

[K man]

Ok, so I ended up ordering both the WONDOM AA-AS41115 and the ADC board.

The WONDOM was a catastrophe. First of all I got a unit that was clearly used, with lots of smaller marks and scratches on the front and back panels. It was not even clean, but had some stain of fat or oil of some kind on the back panel. Connected through toslink to my miniDSP, even with no input connected at all to the WONDOM, the miniDSP was showing some fluctuating background noise around -60 and -70dB. That was not just audible but very present in the speakers. I had to turn down the volume on the miniDSP from 0dB to -20dB before I had a hard time hearing it - at 3m distance...

The ADC board seems to have none of those problems though. The miniDSP is showing background noise around -100dB, which is not audible at all (in my case), and just seem to do its job properly. (Unfortunately I don't have any equipment to electronically measure the performance of it, but there are at least no obvious issues with it.)

The WONDOM will be returned to Audiophonics. I'm still surprised they sent me such worn device with no information about it, but I guess I'm not the first one to return it...

 

[Roland68]

Ok, so I ended up ordering both the WONDOM AA-AS41115 and the ADC board.

The WONDOM was a catastrophe. First of all I got a unit that was clearly used, with lots of smaller marks and scratches on the front and back panels. It was not even clean, but had some stain of fat or oil of some kind on the back panel. Connected through toslink to my miniDSP, even with no input connected at all to the WONDOM, the miniDSP was showing some fluctuating background noise around -60 and -70dB. That was not just audible but very present in the speakers. I had to turn down the volume on the miniDSP from 0dB to -20dB before I had a hard time hearing it - at 3m distance...

The ADC board seems to have none of those problems though. The miniDSP is showing background noise around -100dB, which is not audible at all (in my case), and just seem to do its job properly. (Unfortunately I don't have any equipment to electronically measure the performance of it, but there are at least no obvious issues with it.)

The WONDOM will be returned to Audiophonics. I'm still surprised they sent me such worn device with no information about it, but I guess I'm not the first one to return it...

I think Audiophonics simply made a mistake with the Wondom and someone picked up the wrong shelf. They usually sell such products through their refurbished department.
Normally this box works very well, even if not at the top end of the measurement scale.

It's great that the ADC board works well for you too.

 

[wouter]

I'm looking for something similar to connect my turntable to a S/PDIF input. I'm currently deciding between the Pro-Ject Optical Box E and the PCM1804 board from Audiophonics. @K-man did you get the switching 5V/1A supply from Audiophonics, or would you recommend going with something else?

 

[K man]

I'm looking for something similar to connect my turntable to a S/PDIF input. I'm currently deciding between the Pro-Ject Optical Box E and the PCM1804 board from Audiophonics. @K-man did you get the switching 5V/1A supply from Audiophonics, or would you recommend going with something else?

I purchased the 5V adapter from Audiophonics, but it was purely out of convenience. Any USB charger would do, as long as you have a USB A or C (depending on what charger you have) to 5.5/2.1mm plug cable.

Since your source is a turntable I think you might be better off with the Pro-Ject Optical Box E, since it has phono input. The PCM1804 board has line in with no gain, meaning you'll have a much lower level on the digital output. If you can compensate for that downstream, the PCM1804 board has such a low noise floor that you might be fine either way, but it's worth being aware of.