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Batting ? Bating isn't a word in that context . And what about you being in a 'fray'? This isn't fight club .
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Topping Pre90 Review (preamplifier)
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I've done that, but I didn't find it very informative.
Background: when I started as an EE there were still some line-level 600 Ohm audio installations. These operated with 600 Ohm output impedance feeding 600 Ohm input impedance. They worked fine.
The 1:10 ratio is a rule of thumb, known as impedance bridging: it's not a cast iron rule that must never be broken.
The 600:600 Ohm line-level impedance matching approach I mentioned above, maximises power transmission, vs maximising voltage transmission with impedance bridging. The result of impedance matching is up to a 6dB signal reduction compared to bridging, it's also less efficient, but it can reduce noise. As we both agreed, this signal reduction in a sighted comparison made without controls is probably what the listener noticed.
Low input impedances means the source does need to source and sink more current. But (considering the current through the load) at 2V, into a 10k load impedance (single ended) that's 0.2mA; at 4V into 2K (balanced) it's 2mA. The source should easily be able to supply that.
Is one of the optimal input impedance values for general audio devices about 100kohm? (Is Balance about 200kohm?)
At this link, we measured 1.9kohm load and 46.6kohm load, but no problems were found.
www.audiosciencereview.com
www.audiosciencereview.com
The balanced output of a hifi device should not cause any problems with a 2kohm load.
The balanced output of a vintage device should also not cause any problems. At that time, there were more devices with an input impedance of 600ohm than there are today.
I don't know about vacuum tube devices or boutique audio devices.
By my standards, a balanced output device that has problems with a 600ohm load is defective.
For unbalanced output, is a 10kohm load the lower limit? If it's a modern DAC, a 1kohm load may be fine.
That's all for the numbers, but anyway, enjoy it with your favorite device or system. Ignore other people's complaints.
However, if you are going to discuss superiority or inferiority in a scientific setting, you need scientific evidence. For audio, this is either proper measurement or blind, controlled listening test results.
At this link, we measured 1.9kohm load and 46.6kohm load, but no problems were found.
Schiit KARA Preamp and Headphone Amp Review
... However, Topping adopts that off standard very low impedance for balanced inputs that is a try and error situation. ... Yeah, that seems to be an example of chasing specs at the cost of practical utility. The non-standard low input impedance makes it less flexible/practical/useful...
www.audiosciencereview.com
Topping Pre90 Review (preamplifier)
Hi, I have the same setup: Denafrips Ares II, VTV Purifi with the EVAL1 input buffer and the Topping Pre90 and I would like to know the best way to connect them. If I use the RCA outs on the DAC instead of the XLR does it fix the impedance issue? If not, what should I do? Thanks!!!
www.audiosciencereview.com
The balanced output of a hifi device should not cause any problems with a 2kohm load.
The balanced output of a vintage device should also not cause any problems. At that time, there were more devices with an input impedance of 600ohm than there are today.
I don't know about vacuum tube devices or boutique audio devices.
By my standards, a balanced output device that has problems with a 600ohm load is defective.
For unbalanced output, is a 10kohm load the lower limit? If it's a modern DAC, a 1kohm load may be fine.
That's all for the numbers, but anyway, enjoy it with your favorite device or system. Ignore other people's complaints.
However, if you are going to discuss superiority or inferiority in a scientific setting, you need scientific evidence. For audio, this is either proper measurement or blind, controlled listening test results.
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