Well it's not super clean, that's for sure. Don't think I'd use this for critical measurements. But for a DUT I like to use the same DAC/ADC unit and that can be super clean. For testing tubes, transformers, crossovers, etc.
Ho hum. Another day, another dollar.
Another zillion OT posts about testing jkeny's battery modification and we're finally back to arguing about the effects of RF attenuators on jitter. No-one has been able to demonstrate an effect on the recovered DAC clock and no-one has showed a difference in the audio output either by measurement or by controlled audio test.
So nearly 500 posts later my original objection, that RF Attenuators = Jitter Reducers is NOT PROVEN remains true.
jkeny is driven back to asserting 'So reflections that superimpose on the signal can shift this level & cause jitter !', but he still has no substantial evidence to demonstrate that this is occurring, or that substantial improvement is obtainable with RF attenuators, either in the case of the Hiface, or more generally and particularly in the case of resistively terminated SPDIF receivers, which constitute the very large majority in the market place, and which, I take great pleasure in reiterating, can have their termination checked with no more sophisticated apparatus than a DMM.
It remains my recommendation that no-one should include RF attenuators in their SPDIF connections without being aware that this is likely in the vast majority of cases to cause MORE HARM THAN GOOD, and it will be impossible to definitively tell what the effect has been without the purchase of equipment whose cost will, in all probability, exceed the cost of the original equipment by a considerable margin and the acquisition of skills not posessed by the OP.
w
Another zillion OT posts about testing jkeny's battery modification and we're finally back to arguing about the effects of RF attenuators on jitter. No-one has been able to demonstrate an effect on the recovered DAC clock and no-one has showed a difference in the audio output either by measurement or by controlled audio test.
So nearly 500 posts later my original objection, that RF Attenuators = Jitter Reducers is NOT PROVEN remains true.
jkeny is driven back to asserting 'So reflections that superimpose on the signal can shift this level & cause jitter !', but he still has no substantial evidence to demonstrate that this is occurring, or that substantial improvement is obtainable with RF attenuators, either in the case of the Hiface, or more generally and particularly in the case of resistively terminated SPDIF receivers, which constitute the very large majority in the market place, and which, I take great pleasure in reiterating, can have their termination checked with no more sophisticated apparatus than a DMM.
It remains my recommendation that no-one should include RF attenuators in their SPDIF connections without being aware that this is likely in the vast majority of cases to cause MORE HARM THAN GOOD, and it will be impossible to definitively tell what the effect has been without the purchase of equipment whose cost will, in all probability, exceed the cost of the original equipment by a considerable margin and the acquisition of skills not posessed by the OP.
w
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Yepp! But a linear device will only have linear effects, meaning that the relation between the main signal and the disturbances remain the same.
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Reflections will only cause grief if the cable's incorrectly terminated at both ends. As long as you're terminating the receiving end correctly, you won't see any effects.
Try terminating with something wildly inappropriate e.g. 1K and you should see differences (assuming the output impedance of jkeny's doodad is as bad as he claims it is).
This assumes that you know you have a bad connector causing you impedance mismatches - I suppose you, Waki, would find this out using a DMM? Others would have more difficulty doing this.
This was meant as a cheap experiment - you can leave it in place or fix up the whole signal path if you wish & have the time, etc. nobody stopping anybody doing this - just as nobody should be stopping anybody experimenting with attenuators
This was meant as a cheap experiment - you can leave it in place or fix up the whole signal path if you wish & have the time, etc. nobody stopping anybody doing this - just as nobody should be stopping anybody experimenting with attenuators
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Indeed, & a lot of people are stuck with RCA connectors at both ends - so it might be interesting for SY to try a mistermination or put an BNC/RCA adaptor in along with the attenuators
Jeez, Waki, you just said this a page back
I'm not bad-mouthing you! You never suggested to use a scope to find this out. Is this what you're saying now or how do you suggestthis should be discovered?
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This is the whole point of the thread Pano, if you read the first page & what Waki got all exercised about (& dragged this thread wildly OT), that I was saying I was running down the whole e'ee community by suggesting that terminations weren't well designed in a lot of cases & where his famous quote of using a DMM to measure impedance came from!
Some PC soundcards put out a high SPDIF signal as do some CDPs - so this isn't just limited to the Hiface.
I was hoping that the experiments would reveal these sort of issues
Have to say I trust my ears far more than measurements. On the 4 dacs I've tried in each case they give better resolution, better bass and treble and especially so in musically dense passages.
It's not that I don't trust Sy measurements - hell I'm using his rld amp here daily - but obviously measurements aren't measuring whatever is going on. And please don't tell me that measurements of a single frequency wave is the same thing as a musical passage.
As for cost - the attenuators cost about 15 dollars. Can't do harm except destroy stubborn viewpoints. Don't tell me we haven't all wasted more than that on caps at some point.
Fran
Ps pano - sorry about the ot posts a few pages back. Couldn't resist!
It's not that I don't trust Sy measurements - hell I'm using his rld amp here daily - but obviously measurements aren't measuring whatever is going on. And please don't tell me that measurements of a single frequency wave is the same thing as a musical passage.
As for cost - the attenuators cost about 15 dollars. Can't do harm except destroy stubborn viewpoints. Don't tell me we haven't all wasted more than that on caps at some point.
Fran
Ps pano - sorry about the ot posts a few pages back. Couldn't resist!
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