Yet another A/B test of DACs

[Blumlein 88]

My DMM has already arrived. Is it ok if I use this cable to attach to DAC and do AC voltage measurements ?
View attachment 111873
I will match both AC voltages coming out of the two DACs with 1khz tone. After voltage match, I will then attach the two dacs to AB switch and then to the amp. I'm asking this as I don't want to unnecessarily damage my DAC while putting the DMM leads at the 3.5mm jack during measurements. Thanks

Shouldn't cause any problem at all.

 

[Pdxwayne]

My DMM has already arrived. Is it ok if I use this cable to attach to DAC and do AC voltage measurements ?
View attachment 111873
I will match both AC voltages coming out of the two DACs with 1khz tone. After voltage match, I will then attach the two dacs to AB switch and then to the amp. I'm asking this as I don't want to unnecessarily damage my DAC while putting the DMM leads at the 3.5mm jack during measurements. Thanks

I simply connect regular RCA cable to RCA out of DAC. The other end of RCA cable not connect to anything. Then I use DMM to measure that other end of RCA cable.

 

[raif71]

Ok for my AB tests of DAC, the setups are DACs (Topping D10s and Audio-GD R2R11), using Topping L30 as amp. The setup is as below:

Both of DACs are connected to a switch as inputs and the out of the switch is connected to input of amp. Hiby R5 provide the tone and music via usb to D10s and the coax out of D10s connect to coax in of Audio-GD R2R11. The voltages measured using 1khz tone:

I had to tune the R2R11 volume using its variable volume mode but I couldn't really get to the output of D10s but methinks close enough, right?

Based on the music I listened to basically pop songs, when switching between the DACs , I couldn't really tell any difference between them. To me they sound the same so I decided not to do blind testing.

Moving forward from this, I will proceed with amp AB testing next.

 

[Blumlein 88]

Ok for my AB tests of DAC, the setups are DACs (Topping D10s and Audio-GD R2R11), using Topping L30 as amp. The setup is as below:

View attachment 111879

Both of DACs are connected to a switch as inputs and the out of the switch is connected to input of amp. Hiby R5 provide the tone and music via usb to D10s and the coax out of D10s connect to coax in of Audio-GD R2R11. The voltages measured using 1khz tone:

View attachment 111880

I had to tune the R2R11 volume using its variable volume mode but I couldn't really get to the output of D10s but methinks close enough, right?

Based on the music I listened to basically pop songs, when switching between the DACs , I couldn't really tell any difference between them. To me they sound the same so I decided not to do blind testing.

Moving forward from this, I will proceed with amp AB testing next.

I applaud you for what you are doing.

Just for my curiosity, did you think before trying it that the D10 would sound the same as the Audio-GD?

 

[raif71]

I applaud you for what you are doing.

Just for my curiosity, did you think before trying it that the D10 would sound the same as the Audio-GD?

I thought that audio-gd being an r2r dac, would sound different which I indeed believed was different before this AB and level matching exercise

 

[raif71]

I thought that audio-gd being an r2r dac, would sound different which I indeed believed was different before this AB and level matching exercise

Of course level matching the R2R11 to D10s is just one small part of the equation. The bigger picture is that the R2R11 is better in the sense that at variable DAC mode, it can go max 5V and when I feed this to the L30, I don't even need the L30 in high gain mode!! I can hear my slow classical music in 0db mode whereas using E30 or D10s will never let me do this.

Edit: In this case, level-matching both DACs limit the r2r11 DAC to its full potential and that is handicapping it

 

[raif71]

As mentioned, for my next AB test is between 2 amps which are Schiit Magni 3+ and SMSL SP400. Both of the amps will be fed by Topping D10s DAC. Setup as follows:

I will do matched level AC Voltage at the output of Magni 3+ and SP400 before connecting the 6.5mm of the amps to 3.5mm inputs of the switch. I will slightly use loud volume from the amps but they will be level matched as I can control volume from the switch to get it to low or loud. This is just a plan before the execution of the AB test. I plan to use Senn hd600 and hd800.

 

[Pdxwayne]

As mentioned, for my next AB test is between 2 amps which are Schiit Magni 3+ and SMSL SP400. Both of the amps will be fed by Topping D10s DAC. Setup as follows:

View attachment 115590

I will do matched level AC Voltage at the output of Magni 3+ and SP400 before connecting the 6.5mm of the amps to 3.5mm inputs of the switch. I will slightly use loud volume from the amps but they will be level matched as I can control volume from the switch to get it to low or loud. This is just a plan before the execution of the AB test. I plan to use Senn hd600 and hd800.

You have excellent headphones!
I am curious, using your hd600 and hd800, any difference between them, in term of their ability to hear those online test tones?

For example, any difference in trying the dB change and pitch tests in https://www.audiocheck.net/blindtests_index.php?

Thanks!

 

[raif71]

You have excellent headphones!
I am curious, using your hd600 and hd800, any difference between them, in term of their ability to hear those online test tones?

For example, any difference in trying the dB change and pitch tests in https://www.audiocheck.net/blindtests_index.php?

Thanks!

I've never connected my laptop/pc to DACs and Amps. My laptop/pc shall only be used for doing computer work. I only use DAPs to connect to my music gears ie DACs and Amps. Don't get me wrong though on not ever listening to music via laptop or pc but those will be only utilizing onboard dac and onboard speakers or occasional cheap external laptop speakers. I don't think my Senns will be suitable to connect to the laptop or pc.

 

[solderdude]

You have excellent headphones!
I am curious, using your hd600 and hd800, any difference between them, in term of their ability to hear those online test tones?

For example, any difference in trying the dB change and pitch tests in https://www.audiocheck.net/blindtests_index.php?

Thanks!

With test tones there are no differences between headphones unless one of them distorts substantially at the used frequency.

 

[Pdxwayne]

I've never connected my laptop/pc to DACs and Amps. My laptop/pc shall only be used for doing computer work. I only use DAPs to connect to my music gears ie DACs and Amps. Don't get me wrong though on not ever listening to music via laptop or pc but those will be only utilizing onboard dac and onboard speakers or occasional cheap external laptop speakers. I don't think my Senns will be suitable to connect to the laptop or pc.

If you have recent smartphone that can connect to external device via OTG cable, that should work too.

 

[raif71]

If you have recent smartphone that can connect to external device via OTG cable, that should work too.

I think the Hiby R5 can navigate the blindtest site you mentioned. Perhaps I'll give it a try after the amps AB testing

 

[Pdxwayne]

With test tones there are no differences between headphones unless one of them distorts substantially at the used frequency.

Yup, curious if distortion difference between headphones could make one better than the other.

 

[Rottmannash]

That's not a comparator. This is a comparator! (apologies to Croc Dundee)

View attachment 108459

WTH is that??

 

[raif71]

As stated, here is my setup to AB test of 2 amps - the Schiit Magni 3+ and SMSL SP400. The level matched measurements using 1khz tone

I tried to get as close as possible the measurements but at difference of 5.1mV, I did not perceive any differences with pop songs. Both sound equally good with hd600 and hd800. Dac used is the Topping E30.

E30 with rca splitter to split two R/L to 2 amps