[seaice]

What I have learned so far, the Chord M Scaler upsampling should be really good, perhaps superior to many upsampling methods used in other products. Of course, only my own experience will show me if it is the case. I plan to the M Scaler primarily with my Chord Dave but, of course, I am curious what it could bring to my other DACs as well, especially to my A-Gd HE-7 Singularity. Unfortunately, A-Gd DACs have input limitations - they are not capable of receiving full 705.6/768kHz output of the M Scaler so I probably can not use the full TAPS lenght of the M Scaler for A-Gd DACs.

 

[Whitigir]

What I have learned so far, the Chord M Scaler upsampling should be really good, perhaps superior to many upsampling methods used in other products. Of course, only my own experience will show me if it is the case. I plan to the M Scaler primarily with my Chord Dave but, of course, I am curious what it could bring to my other DACs as well, especially to my A-Gd HE-7 Singularity. Unfortunately, A-Gd DACs have input limitations - they are not capable of receiving full 705/768kHz output of the M Scaler so I probably can not use the full TAPS lenght of the M Scaler for A-Gd DACs.

Have you ever heard a dedicated built PC with HQPlayer doing Upsampling job yet ? I love it upto 192Khz and even DSD512. But I prefer pcm in I2S directly and it is only 192Khz

Longer taps length may be a thing where Chord Pulse Arrays can shine and not any other brands. Just look at IFI IDSDPro, they stated shorter is better...sooo...

 

[seaice]

I have tried several upsamplers with foobar2000, jriver and other programs but never tried HQPlayer.

 

[Alireza326]

hi all
I recently measure my speaker response with dayton audio UMM-6 Mic and REW software and find out a problem
with master 7 connected my response fall steeply above 14.3khz
I checked response with NFB-28 and all things are ok
I own older version of master 7 and firmware updated to last firmware that kingwa provided
any suggestion what is the problem? any one else do the same measurements?
thanks in advance

 

[Alireza326]

Kingwa checked out my Singularity digital board that I sent back and found no issue. The issue I experienced was when installed in my old Master 7 chassis only 1 in 10 power cycle boots had good audio on 44.1Khz sample files. Otherwise sound was muffled with loss of highs, slightly lower gain, and grainy vocals. It was immediately noticeable when bad.

Kingwa offered to refund my money but I asked Kingwa to ship back a different board for a 2nd try. I am happy to report the new board works much better. On a cold start up the audio is always good and remains OK until power is switched off. I can restart the M7S in the first hour and still have good audio. After several hours of operation with Master 7S good and warm does the same problem show up. But shows up less frequently than previously experienced with the first board. The new Singularity digital board started up OK 7 days straight.

I feel like this is a victory as I have an upgraded M7 that works. Rarely do I reboot a warm DAC. It gets turned on early in the morning and left on until no longer needed and shut off overnight. Here's a video (below) of my experience with the latest digital board. The video captures the audio of my warmed up system and is broken into three segments. The first segment, where audio is normal, is followed by two power cycles of the M7S. You will notice less highs (muffled) and gain after the two warm power cycle restarts.

https://1drv.ms/v/s!AqFmDQboxG1jgWsiar5k7E5GSwd_

I was googling for above mentioned problem and hope to find any solution, and lead me to your post
I also have this problem
randomly my M7 sounds ok but occasionally mids sound bad and loss in high is obvious so tend me to buy measurement mic for measurements
so did you solve your problem?

 

[aljordan]

hi all
I recently measure my speaker response with dayton audio UMM-6 Mic and REW software and find out a problem
with master 7 connected my response fall steeply above 14.3khz
I checked response with NFB-28 and all things are ok
I own older version of master 7 and firmware updated to last firmware that kingwa provided
any suggestion what is the problem? any one else do the same measurements?
thanks in advance

How steeply are you talking about here? I think it is natural for the Master 7 to have a slow roll-off from about 13k to 20kHz, but it is only down about 0.5 dB at 20 kHz. This is measured through an audio interface, not the speaker.

 

[Alireza326]

How steeply are you talking about here? I think it is natural for the Master 7 to have a slow roll-off from about 13k to 20kHz, but it is only down about 0.5 dB at 20 kHz. This is measured through an audio interface, not the speaker.

about 10 db from 14khz to 20khz
also mention that I connect to M7 via USB
yep, you're correct about measurement but with nfb28 high frequency response looks ok
I will attach Measurement Pictures of M7 and NFB28 as soon as I can ( now my wife is sleeping )

 

[aljordan]

about 10 db from 14khz to 20khz
also mention that I connect to M7 via USB
yep, you're correct about measurement but with nfb28 high frequency response looks ok
I will attach Measurement Pictures of M7 and NFB28 as soon as I can ( now my wife is sleeping )

Did you keep the measurement mic in the exact same position when you compared the measurements from both DACs? I could see in room response being down quite a bit if the measurement was taken at the listening position.

 

[aljordan]

How steeply are you talking about here? I think it is natural for the Master 7 to have a slow roll-off from about 13k to 20kHz, but it is only down about 0.5 dB at 20 kHz. This is measured through an audio interface, not the speaker.

Here is a screen grab of the measurements I was referring to. The top orange line is the Master 7, the middle blue line is the Schitt Yggy via its RCA outputs. The bottom line is the Prism Sound Orpheus. The Yggy and the Master 7 were tested using the SPDIF (RCA style) input. Master 7 is my favorite DAC to listen to out of the three, even though it shows the mild high frequency roll-off.

 

[Alireza326]

thanks aljordan for your help
yes, I measure M7 and swap to NFB28 with out changing anything including Mic position
I use M1 as pre amp and attach NFB28 to M1 input to ensure that problem is not from M1
did you use digital oscope to catch above graph? unfortunately I have an old analog scope and therefore it cant get FFT and hard to work with
after some try only one time response of M7 and NFB28 match exactly but i think it is random
so what can I do? I hope that can bring lovely M7 to life again

 

[FredA]

thanks aljordan for your help
yes, I measure M7 and swap to NFB28 with out changing anything including Mic position
I use M1 as pre amp and attach NFB28 to M1 input to ensure that problem is not from M1
did you use digital oscope to catch above graph? unfortunately I have an old analog scope and therefore it cant get FFT and hard to work with
after some try only one time response of M7 and NFB28 match exactly but i think it is random
so what can I do? I hope that can bring lovely M7 to life again

The m7 needs some warm up time before it plays normally. Just in case you did not know.

 

[Alireza326]

dear FredA
I know that
but I think it doesnt related to frequency response , correct me if I'm wrong
any way I repeat mesearements after couple of hours to ensure M7 warm up enough

 

[DACLadder]

Which DSP operational mode are you using - OS or NOS? I believe NOS rolls off to -3dB. The Yggy is interesting as it rolls off about -3dB on low side starting at 200 Hz.

 

[Alireza326]

Which DSP operational mode are you using - OS or NOS? I believe NOS rolls off to -3dB. The Yggy is interesting as it rolls off about -3dB on low side starting at 200 Hz.

I never understand which DSP mode is ( audio gd site info is confusing)
but, jumper is on bypass situation , I think it is kingwa's default configuration
older versions of M7 doesn't support NOS mode as I know
probably it would be better to find a digital scope to test RCA and XLR out put
I really confused what is happened and how i can repair it

 

[DACLadder]

was googling for above mentioned problem and hope to find any solution, and lead me to your post
I also have this problem randomly my M7 sounds ok but occasionally mids sound bad and loss in high is obvious so tend me to buy measurement mic for measurements
so did you solve your problem?

That was an interesting issue with conversion of the old M7 to SIngularity DSP. For whatever reason the 1st Singularity board sent to me would not boot up consistently. I sent this board back to Kingwa and he said he could no find an issue. I had him send me a 2nd board that did much better. I did not completely resolve the issue as the old M7 was packed up and moved about the same time. The 2nd replacement board was better but could get it to do the same on repeated restarts of the warm DAC. Cold DAC starts are OK. The AGD procedure now is to wait 30 sec. before reapplying power.

The issue was discovered while constantly rebooting a warm DAC testing various DSP modes. But if the DAC sounds OK from the beginning then it will sound good until possible another power restart. Others users did not have this issue and my other two SIngularity DSP equipped DACs never have issue unless I don't wait enough time before reapplying power.