Please, don't do that (audio trasfo). they are terrific if not super hight quality, and will destroy all the performance of your set-up. And they are super expensive if high quality.
May-be you have some margin of gain ? Add a resistance bridge or a potentiometer to reduce the volume and so, the noise of the DAC.
May-be you have some margin of gain ? Add a resistance bridge or a potentiometer to reduce the volume and so, the noise of the DAC.
But a cheap or borrowed one is great to try out with to see if it helps.
A carbon potentiometer is probably not a great solution either. There is definitely gain margin, I would suggest removing the resistor from the feedback network to drop the gain, but I remember all too well my own fumbling when trying to remove it... OK, someone who takes the time and uses a proper magnifying glass should be able to pull it off without problems.
How do those differ from a resistive based in line attenuator like this?
Sescom Sescom SES-IL-10DB XLR Male to XLR Female In Line Attenuator - 10db Impedance Matching Transformer at Markertek.com
Sescom Sescom SES-IL-10DB XLR Male to XLR Female In Line Attenuator - 10db Impedance Matching Transformer at Markertek.com
Just wanted to follow up from a prior post regarding issues I having with my NCores. I'd been away for a couple weeks and wasn't able to get around repairs until recently. An employee at Hypex suggested a possible issue with my speaker posts not being isolated properly. I believe this is where the issue lied. Another problem may have been bad contact due to the binding posts being annealed. Lastly I purchased one of these Line-R 1200VA Automatic Voltage Regulator suggested by Bavmiike. In one fell swoop made all changes and hooked them up and they work perfectly. Furthermore I believe the apc voltage regulator has improved them to worthwhile degree. I sexond Bavmiike's observations and recommend it for digital components with SMPSs. Thank you for the suggestions and thought and also thanks to the people of Hypex in their ability to isolate the issue from fairly junky iphone pictures.
A resistive attenuator doesn't provide any isolation. A transformer gives galvanic isolation from ground issues, and is pretty good at blocking HF noise too.
for the same reason you have to spend good money on them to get good results, severe bandwidth limitations
robbby, why not try to ask other Mytek users, maybe at computer audiophile? maybe it's a known issue?
my DAC (made by a small local company) had similar issues, made an annoying noise audible even in a less than perfectly quiet room. returned it to the manufacturer and he fixed it, said it was related to some unannounced changes in the output buffer made by the manufacturer (TI). obviously this may have nothing to do with your problems but just sayin'...
my DAC (made by a small local company) had similar issues, made an annoying noise audible even in a less than perfectly quiet room. returned it to the manufacturer and he fixed it, said it was related to some unannounced changes in the output buffer made by the manufacturer (TI). obviously this may have nothing to do with your problems but just sayin'...
Most decent ones go to well over 20 kHz...
Again, the reason I am suggesting a cheap one (or getting one on loan) is to see if the galvanic isolation solves the problem.
If the hiss is generated by the DAC output circuit, and if any volume margin available, providing some attenuation in input will increase the signal/noise ratio, thus reduce the hiss by the ratio of attenuation. 2 resistances, not a big deal.
That's a broad generalization that could apply to any piece of electronics, not very constructive.. An example of a very nice xformer with stellar performance (not cheap ~$190,00 but very good imho)
http://www.jensen-transformers.com/datashts/dm2xx.pdf
Sure - but if the problem is some ground loop or HF oscillation interaction with the DAC, as opposed to a pure DAC problem, we don't just want to attenuate the problem, we want to get rid of it.
"Oh lord, oh won't you buy-me a Mercedes Benz..."
60% the price of the amp, for something you cant assure it will solve the issue ? Very constructive, indeed.
So how many times do I need to repeat "I am suggesting a cheap one (or getting one on loan) to see if the galvanic isolation solves the problem"?
I agree, Mark - audio transformers can be surprisingly good, and even their error modes aren't too bad (limited "ultrasonic" range, soft clipping when overdriven).
Additionally...
Some nCore users have reported excellent improvements in sound quality when coupling a DAC to the nCore via a tranformer of some type. Output transformers in the DAC, TVCs, and input transformers in the amp have been reported to result in sound quality improvements.
I noted that one DAC I tried with the nCore produced a course grainy noise floor (still only audible with an inch from tweeter), and have come to suspect that the nCore is sensitive to RF on its input (as are many class D amplifiers).
So, as Julf is pointing out, there may be additional benefits to reducing the gain of the Mytek DAC via a transformer which would justify the high price. Also, going amp direct, using a transformer to step down the voltage a little increases the current drive vs using a resistor based solution, and I find having higher current availability is a good thing when driving amplifiers directly as well.
Some nCore users have reported excellent improvements in sound quality when coupling a DAC to the nCore via a tranformer of some type. Output transformers in the DAC, TVCs, and input transformers in the amp have been reported to result in sound quality improvements.
I noted that one DAC I tried with the nCore produced a course grainy noise floor (still only audible with an inch from tweeter), and have come to suspect that the nCore is sensitive to RF on its input (as are many class D amplifiers).
So, as Julf is pointing out, there may be additional benefits to reducing the gain of the Mytek DAC via a transformer which would justify the high price. Also, going amp direct, using a transformer to step down the voltage a little increases the current drive vs using a resistor based solution, and I find having higher current availability is a good thing when driving amplifiers directly as well.
sounds like what my DAC was outputting. kind of like a modulated buzzing noise.
Well. it is a little like tube amps (because the use audio transformers ? ;-). Quite a natural sound, kill the magic of very fast systems.
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