Not very elegant, indeed.
And yes, that's how these things are used.
Except when you run out of pairs in the right direction on a multipair, as PeteL explained above.
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Neutrik NA2M-D2B-Tx balancing transformer adapter review
- Thread starter pma
- Start date
And yes, that's how these things are used.
Except when you run out of pairs in the right direction on a multipair, as PeteL explained above.
Nice review.
* to low usable voltage range is it not ?
* demanding on the impedance the line driver ? Many preamps are not better than 100-200Ohms ? It’s of no consequence in a typical hifi and is fine. Maybe a mixer has a better line output in the usable range of 10’s of ohms ?
But I would throw a couple of them in my bag if I was on tour on with a band or some such. It’s a problem solving thingy ! for a permanent install you actually do something else I think ?
* to low usable voltage range is it not ?
* demanding on the impedance the line driver ? Many preamps are not better than 100-200Ohms ? It’s of no consequence in a typical hifi and is fine. Maybe a mixer has a better line output in the usable range of 10’s of ohms ?
But I would throw a couple of them in my bag if I was on tour on with a band or some such. It’s a problem solving thingy ! for a permanent install you actually do something else I think ?
solderdude
Grand Contributor
But the conclusions that were drawn differ because of the (assumed) application and above all used levels.
If one were designed for XLR-> RCA and the other one RCA->XLR and Neutrik believes their own transformer is 'directional', as indicated per the loading (would need to be confirmed, the pic is inconclusive) then the 2 versions only seem to differ in XLR gender.
The transformer usage and documentation seems to suggest it is designed for RCA -> XLR (-10dBV), the connectors seem to suggest they have different directionality but do not seem to be designed that way unless for some reason a 47k is really only connected between hot and common/ground (@pma can confirm) but the schematic seems to suggest a load. 47k, however, would be a pointless value.
The device remains a weird one and perhaps why Neutrik is so 'vague' in description/information and could be used as an on-site quick fix/tool to solve groundloop alike issues but is rather limited in application.
Well, semantic could be debatable. If you use a balanced source ans you connect it to a rca input without using a transformer like tis one you still have an unbalanced line and you don't get the benefit of CMNR so technically, even when plug in a rca input, this still act as a balancing adapter because the line stays balanced all the way till you reach the adapter which also make sense for long run of cables.
Anyway, the only question, really, is:
Do they work correctly in both directions ?
As they are passive and with 1:1 transformer, one could expect so.
But that's not necessarily the case (as an example, since you have this resistor on the XLR side in both cases).
solderdude
Grand Contributor
manisandher
Addicted to Fun and Learning
Hear hear!
But in this case, I guess you meant "posterity"?
I have a couple of NA2F-D0B-TX adapters that I intended to use to convert balanced output from my Okto dac8 PRO into SE input into mono amps, to drive the subs in my 4-way active setup (<60Hz). The Neutriks were clearly not up to the job, so I abandoned them and got amps with balanced inputs. Both sets of measurements here show why they failed for my intended purpose.
But I can see that they might be fine just to break ground loops.
Mani.
Amir's measurments (so opposite direction) Show a flawed design, but not that it's not "working correctly". It will still act as a transfo, do what a balance line is suppose to do. As @solderdude mentioned, this resistor is not doing anything in term of loading, pma measured the resistance on both side, it's 43.4 ohms on the XLR side and 56.8 ohm on the rca side, it's a 1:1 transfo, we have printed documentation that show the same exact schematic on both version, Neutrik don't advertise any signal direction don't label outputs or inputs on neither, so yes, we can expect so. We have differences, but it's because PMA used a very low impedance source and lower levels. I think the conclusions are the same in the end, at least we can draw our own, it's that it's not a high fidelity device, but I really see no indications that you can't plug this into a rca Input, If Neutrik didn't want us to do so they would tell us so and would not make a female version just to bluff people. We can be critical of performance but come on, Neutrik know that If you make a female XLR in one end and a rca on the other and mention nothing, they know full well that people will plug them in a RCA input. It's Neutrik, they know that.
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- Thread Starter
- #51
As there were some doubts in the other thread about behaviour of the adapter in opposite direction, I am posting THD vs. frequency measurements taken in both directions:
1) XLR input ==> RCA output (orange)
2) RCA input ==> XLR output (violet)
There are no doubts that the adapter works almost same in both directions.
1) XLR input ==> RCA output (orange)
2) RCA input ==> XLR output (violet)
There are no doubts that the adapter works almost same in both directions.
You should add that to the first post, IMO
It will be useful for everyone.
It will be useful for everyone.
- Thread Starter
- #53
Thank you for the hint, done. Also added frequency responses comparison in both directions.
solderdude
Grand Contributor
- Thread Starter
- #56
I have just made measurements with 200 ohm driving impedance, load impedance remained 1.66 kohm.
Distortion vs. frequency - worse, but not as much as I expected
Frequency response, just quick comparison to 0.056 ohm drive (I apologize for not shifting Y scale). Surprisingly still goes down to 40Hz.
THD, THD+N at 1kHz/552mV. About 4x more than with 0.056ohm drive.
REW and STEPS. REW sometimes goes unstable with my DAC/ADC, so time after time I use STEPS, which is stable and saves my time by no need of repeating of measurements.
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I concur that clarification would be great, but there is something I am not getting in your point if you care to quickly explain. Hot and cold in a balanced connection need to have equal impedance relative to the ground, wouldn't putting 47k between hot and ground and not the cold throw that off and hurt cmnr? I am sure that it's me not catching something.
- Thread Starter
- #58
No, it is between (2) and (3). (1) is connected to chassis XLR pin only. Exactly as per schematics they provide. Probably an optical illusion from 2D photo.
- Thread Starter
- #60
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