KTB vs Topping E30 listening tests

[Pdxwayne]

Firstly the output voltage is indeed non-standardised. The convention for modern days is 2V or so for unbalanced output and 4V for balanced output. For traditional home uses and studio uses there can be vast differences.

The main difference you see here is bal vs unbal. E30 and D10s are around 2V, the rest are around 4V, M400 is 5.3V.

Thanks! So the order according to your graph, from highest voltage to lowest voltage output based on -16db input signals:

M400 (Bal)?
Topping D70s (Bal)?
Topping D90 (Bal)?
Topping E30 (unbalanced)
Topping D10s (unbalanced)

Am I correct? Thanks!

BTW, now that 500mV line looks out of place....

 

[JohnYang1997]

Thanks! So the order according to your graph, from highest voltage to lowest voltage output based on -16db input signals:

M400 (Bal)?
Topping D70s (Bal)?
Topping D90 (Bal)?
Topping E30 (unbalanced)
Topping D10s (unbalanced)

Am I correct? Thanks!

BTW, now that 500mV line looks out of place....

 

[Pdxwayne]

View attachment 111298

Excellent! This one is more like I expected. Your previous chart has one at 500mV, which seems strange.

I am assuming all got -16db input signal?

Thank you very much! Again, appreciate your help!

 

[JohnYang1997]

Excellent! This one is more like I expected. Your previous chart has one at 500mV, which seems strange.

I am assuming all got -16db input signal?

Thank you very much! Again, appreciate your help!

I changed to -13dB to be inline with your condition.

 

[Pdxwayne]

I changed to -13dB to be inline with your condition.

Is it correct to assume that the differences in dB, balanced vs balanced, unbalanced vs unbalanced, according to your chart, is audible?

Thanks!

 

[JohnYang1997]

Is it correct to assume that the differences in dB, balanced vs balanced, unbalanced vs unbalanced, according to your chart, is audible?

Thanks!

The level itself is of course audible. But if you level match with downstream component then not audible.

Meaning, if you just swap different DACs leaving the pot position the same, you can hear differences. But this is just caused by the different level. It vanishes when you level match.

 

[Pdxwayne]

The level itself is of course audible. But if you level match with downstream component then not audible.

Thanks for confirming, using as is, the differences are audible.

Definitely agree that when doing blind tests, voltage output should be matched.

The issue I see for many users, including myself, is that they didn't do good enough or did no voltage/volume matching when comparing DAC. All they do is switch DAC using preamp. That is the main reason why many users claimed they heard a difference. That is real difference heard when not voltage/volume matched. They don't have preconceived bias like many here like to claim.

Thank you very much! I hope you don't stay up too late!

 

[Nango]

Any differences with and without that Furman box?

 

[Pdxwayne]

Any differences with and without that Furman box?

Sorry, didn't do comparisons. I use it for peace of mind and it's claimed of extra stored energy for high wattage draws. : )
My subs and amp can do RMS watts of over 3000 watts. I only have 15 amp circuit. So I am hoping to make it up with the Furman.

The Furman are now in used in my downstairs stereo setup that includes X16 as DAC. Sounds great.

 

[BDWoody]

They don't have preconceived bias like many here like to claim.

It's not that they have preconception bias, necessarily. In this case, it's that we are biased towards louder, and even if not for preference, certainly for identification. There isn't just one or two to account for, there are many...

Why do you think everyone had been trying to get you to focus on the level matching? If you are saying that if you don't level match properly, you'll hear a difference, isn't that what we've been saying all along?

It's about setting up two devices with their settings as comparable as possible. Filters, levels, whatever... At that point, the presumption is that they will be indistinguishable under non-pathological conditions. If those conditions aren't met, I'm not sure the point.

 

[Pdxwayne]

It's not that they have preconception bias, necessarily. In this case, it's that we are biased towards louder, and even if not for preference, certainly for identification. There isn't just one or two to account for, there are many...

Why do you think everyone had been trying to get you to focus on the level matching? If you are saying that if you don't level match properly, you'll hear a difference, isn't that what we've been saying all along?

It's about setting up two devices with their settings as comparable as possible. Filters, levels, whatever... At that point, the presumption is that they will be indistinguishable under non-pathological conditions. If those conditions aren't met, I'm not sure the point.

The point is to educate new comers nicely. Not to put them down by claiming all differences heard is imagination! Some here love to do that. I have no issues with doing level matching testing. : P

The big difference I heard between E30 and x16 is bagpipes high notes. Will need to figure that out.

 

[Bob from Florida]

The point is to educate new comers nicely. Not to put them down by claiming all differences heard is imagination! Some here love to do that. I have no issues with doing level matching testing. : P

The big difference I heard between E30 and x16 is bagpipes high notes. Will need to figure that out.

First - spend as much time as you like or is prudent to satisfy your curiosity.
Now - some unsolicited advice.
The prime issue is how to level match. Ideally you would have an oscilloscope to measure the peak to peak voltage level at the frequency chosen at your speakers or headphones. Pick a reasonable level that matches the desired sound pressure level. Adjust as needed when switching components. Not everyone has a scope and maybe the multimeter is not accurate at frequencies other that 60 hertz. In this case set your system to a volume level you find enjoyable. Don't touch the volume control for the next step. Then connect your speaker output to a full-wave bridge rectifier whose output is connected to a capacitor - 100 uf at 100 volts should be fine. A 100 ohm 5 watt bleeder resistor across the capacitor will be sufficient to load the cap. Turn on your signal source and measure the DC voltage that develops across the cap. That voltage will rise and stabilize in a short time. The measured DC voltage is your reference voltage you adjust the volume for when you change components.
This should be reasonably close if your volume control has sufficiently small steps of adjustment when switching your components. All this takes awhile between listening and hopefully your audio memory has not forgotten what things sounded like 5 minutes ago.

 

[Pdxwayne]

First - spend as much time as you like or is prudent to satisfy your curiosity.
Now - some unsolicited advice.
The prime issue is how to level match. Ideally you would have an oscilloscope to measure the peak to peak voltage level at the frequency chosen at your speakers or headphones. Pick a reasonable level that matches the desired sound pressure level. Adjust as needed when switching components. Not everyone has a scope and maybe the multimeter is not accurate at frequencies other that 60 hertz. In this case set your system to a volume level you find enjoyable. Don't touch the volume control for the next step. Then connect your speaker output to a full-wave bridge rectifier whose output is connected to a capacitor - 100 uf at 100 volts should be fine. A 100 ohm 5 watt bleeder resistor across the capacitor will be sufficient to load the cap. Turn on your signal source and measure the DC voltage that develops across the cap. That voltage will rise and stabilize in a short time. The measured DC voltage is your reference voltage you adjust the volume for when you change components.
This should be reasonably close if your volume control has sufficiently small steps of adjustment when switching your components. All this takes awhile between listening and hopefully your audio memory has not forgotten what things sounded like 5 minutes ago.

Thanks for the detail advice!

In my other thread where I compared E30 and X16, I was taught to use loopback to check the devices dB. It can be matched very closely. See https://www.audiosciencereview.com/...my-gustard-x16-measurements.20679/post-688957 for my first such measurement.

Thanks again!

 

[Pdxwayne]

Tracking a very interesting KTB thread. It seems indeed KTB can be harsh (which was the main reason of starting this thread):

Measurements: "ESS Hump" revisited (Khadas Tone Board V1.3)

It turned out that it best to leave the 470F as is and only reduce the series resistor from 100R to 10R. Then the key trick (also seen in older DAC chip's datasheets, like AD1853) was to add a 220pF "transient killer" capitor accross the inputs of the I/V which shorts out fast differential-mode...

www.audiosciencereview.com