Bizarre tech - Nobsound NS05P Pro

[MCH]

I don't think there is a dedicated thread for peculiar devices so posting it here.

Someone please explain me what is a use case for this:

Independent XLR to RCA and RCA to XLR with independent volume control in the same box.I am sure there will be someone that needs one, there always is, just can't imagine what for.

Nobsound NS-05P PRO HiFi XLR Balanced/ RCA Audio Converter

Features Bi-Directional RCA & XLR Converter: Seamlessly transforms RCA (unbalanced) to XLR (balanced) and XLR to RCA. It's the perfect solution for bridging consumer Hi-Fi gear with professional audio equipment, in either direction. True Balanced Circuitry for Pristine Sound: Upgrades your RCA...

doukaudio.com

 

[lorenz]

Hi Mich

It's useful when you want to keep XLR cables at all stages.

My preamp (ZP3) feeds two Fosi V3 Mono amps via XLR.

However, my SMSL SU-1 DAC doesn't have an XLR output.

This converter would allow me to connect the preamp via XLR.

It's an active, bidirectional converter with two independent channels.

Internally, it's fully differential, so the RCA → XLR conversion delivers a real balanced signal, not just pin-adapted.

Ideal for connecting, for example:

An RCA DAC → to an XLR preamp or amplifier

An XLR preamp → to an RCA amplifier.

Being active, it maintains good signal integrity and isolation, with low distortion and wide bandwidth

Use a linear power supply or iPower if you want to avoid noise from a standard USB power supply.

If you hear hissing, ground the GND to the metal chassis of another piece of equipment (preamp, amp, etc.).

The volume knob adjusts the internal gain, but ideally it should be at maximum and the volume controlled on the main stage.

This is a solution for those who want to reuse the equipment, in my case, the DAC. The other option would be to replace the DAC if it already has an XLR output.

It's an additional piece of equipment in the system. It fulfills the conversion role, but you have to pay attention to the power supply you will use and to grounding, if necessary.


The question is:

Including it in the setup costs $60, considering a good power supply (at least $80 for IFI power), good cables (RCA+XLR) cost $50, wouldn't it be better to consider upgrading the DAC?

Either way, it will add THD+N of 0.008% (~-82 dB).

If the goal of migrating to balanced connections (XLR) is:

reduce noise
improve signal-to-noise ratio
eliminate ground loops
have greater immunity to interference in long cables

…then inserting an active converter in the path does the opposite of what is expected.

 

[MCH]

Hey Lorenz,
I am sure there are use cases for it, however, in your case, you only need a regular simple (active if you wish) RCA to XLR converter. With the Nobsound, you will be using half of it.
Your example of someone that has unbalanced sources and amplifiers but a balanced only preamp is a valid use case, but a bit strange imo. As strange as the Nobsound itself haha.

I can really only think on someone using the RCA to XLR for a phono input and the XLR to RCA for a sub output in an otherwise balanced system. There, even the knobs can be useful to adjust that gain.

 

[lorenz]

I'm inclined to invest in a DAC with XLR.
For the current setup, I acquired a good RCA cable to connect the DAC to the preamp.
There were better and more expensive RCA cable options. But if the intention is to upgrade the DAC in the near future, it doesn't make sense.
Anyway, the SU-1 is well-resolved and no noise is noticeable with the connecting cables.

The converter is the kind of product where you gain on one side and lose on the other.

For those who have expensive equipment in the audio chain, with limited output or input, and insist on using XLR, it can be an alternative.

 

[MCH]

Yeah, I think it is your best option. Nowadays you can find cheap ones, and you can offset a bit the cost selling the one you have and you are done forever

 

[sergeauckland]

It has an application in something like adapting a studio quality tape recorder to a hifi system, or alternatively a semi-pro tape machine to a studio system.

Having said that, sales volumes would be pretty limited, and I would much prefer to have seen the volume controls as screwdriver presets, so can be set and left.

S

 

[Curvature]

When converting, there will be 6dB difference in voltage. This device is likely meant to adjust for that difference.

 

[nagster]

Photo of Douk Audio Nobsound NS-05P PRO.

 

[nagster]

Measurements for Douk Audio Nobsound NS-05P PRO.

Edit: Added Channel balance measurement.

 

[MCH]

Measurements for Douk Audio Nobsound NS-05P PRO.

Thanks a lot.
A bit of nitpicking: Is that channel matching at -10 and -20dB good enough?

 

[nagster]

Thanks a lot.
A bit of nitpicking: Is that channel matching at -10 and -20dB good enough?

At -20dB, there's already a difference of more than 0.5dB, so it would be considered "bad" by ASR review standards. But maybe I'm just unlucky.
If you need an exact match, you can add another unit to create a dual mono converter. Each unit costs $60.

 

[nagster]

These are measurements of the Douk Audio Nobsound NS-05P PRO's RCA input / XLR output.

 

[MCH]

@nagster there is a lot of work and interesting results there, you should do a proper thread, maybe there is people interested. I would change the title of this one to indicate there are measurements, but cannot