Groß DAC owner's thread.

[Bill125812]

Holy crap Clay. 

 

I have just plugged in my new GroB dac, that I picked up from Clay on thursday.  It’s replacing a PS Audio Nuwave DSD dac.   No slouch in itself. 

 

Well I’ll that was until I fired up the GroB.  As the title says. Holy crap.  The soundstage just increased.  There is a depth of detail that I’ve never experienced before.  I’ve owned clays Klein and Klein II Dacs but this blows even them away.  I haven’t even touched DSD files yet.  I’m streaming some Tidal MQA titles at the moment through a bluesound node 2.  

 

Lets say im in heaven.  I am now going to start changing some of the filters and see what happens. 

 

Mr Gieseler.  Your a genius 

 

I’ll report Back in a week or so when this little gem has properly burnt In

Edited December 24, 2017 by Bill125812

[Suopermanni]

Okay, tried some high res stuff on the GroB DAC that @bhobba lent me including some DSD from demo pieces from 2L High Resolution Music Test Bench. While I could not really differentiate between the different bit-rates, I was struck by the recordings. It's well done and though way different to what I listen to, it is quite an eye opener. 

 

EDIT: Yes, the GroB DAC does play the DSD via Bitstreaming on JRiver. No need for DoP.

 

EDIT2: Played one of my go-to tracks (mostly because I like it and know it) and I detected some definite differences to now compared to start and to burnt in Gungnir Multibit! Now this is better!

Edited December 23, 2017 by Suopermanni

[bhobba]

23 hours ago, Suopermanni said:

Played one of my go-to tracks (mostly because I like it and know it) and I detected some definite differences to now compared to start and to burnt in Gungnir Multibit! Now this is better!

Yes it will get better with time.  Have been told, via some second hand private feedback, of a comparison that shows again what a giant killer this little DAC is - but need to confirm it personally before I can post.  That will happen early in the new year.

 

Sorry Suopermanni will need it back then for that comparison  - but don't worry - over a week still to go and looking forward to your further impressions 

 

Also when doing comparisons your go-to tracks that you know and like are the best to use.  It's what I always do - but also to be fair listen to some other stuff as well to get a rounded picture.

 

Thanks

Bill

Edited December 24, 2017 by bhobba

[Stereophilus]

@bhobba was your version with the amanero USB board?

[Suopermanni]

59 minutes ago, bhobba said:

Yes it will get better with time.  Have been told, via some second hand private feedback, of a comparison that shows again what a giant killer this little DAC is - but need to confirm it personally before I can post.  That will happen early in the new year.

 

Sorry Suopermanni will need it back then for that comparison  - but don't worry - over a week still to go and looking forward to your further impressions 

 

Also when doing comparisons your go-to tracks that you know and like are the best to use.  It's what I always do do - but also to be fair listen to some other stuff as well to get a rounded picture.

 

Thanks

Bill

@bhobba Of course of course! It is YOUR Dac after all that I'm borrowing. When you need it back, let me know and let's arrange something so I can return it!

[Snoopy8]

49 minutes ago, Stereophilus said:

@bhobba was your version with the amanero USB board?

Yes,he has the Amanero USB only version, see earlier review:

 

Edited December 24, 2017 by Snoopy8
Typos

[Stereophilus]

4 hours ago, Snoopy8 said:

Yes,he has the Amanero USB only version, see earlier review:

 

Hi Snoop,

 

as per here:

I thought @bhobba was ordering the Singxer USB version? I just wondered which version he ended up getting as his report states just that it was the “USB only” version, not whether it was the Amanero or Singxer...

Edited December 24, 2017 by Stereophilus

[Stereophilus]

On 31/08/2017 at 3:46 PM, bhobba said:

Hi Guys

 

Sent Clay an email to order one.  Just spoke to soimeone whose ears I trust, but cant name who was VERY impresssed - that good enough for me.

 

Want the Singxer version.

 

Will be giving Clay a special notebook I have purchased just for Music.

 

It will run HQPlayer and upsample everything to 768K - which is getting close to DSD anyway.  My current experimentation showed music was dull then up-sampled it to DXD (354k) and it came alive.  Used the Direct Stream DAC which does massive up-sampling itself, so obviously HQPlayer up-sampling is better than what the DS does.  But it really up-samples - to 10XDSDS- wow.

 

Thanks

Bill

Sorry, that other link crapped out. The above is what I was referring to.

[Suopermanni]

@Stereophilus I don't think Clay actually successfully managed to use the Singxer in his DAC. I believe Clay mentioned later in the topic that he couldn't use it.

 

EDIT: By the way, I'm getting some weird playback issues occasionally on my WINDOWS 10 PC in that at times, JRiver will refuse to play my music saying the hardware doesn't support its standard rate even though I know it does. 

Edited December 24, 2017 by Suopermanni

[jermaink]

The Singxer F1 does not have the exact same pin layout as the Amanero board as originally thought and isn't a direct substitute for the Amanero, so a Singxer F1 based Groß DAC is unlikely as it would require a significant redesign.

[Suopermanni]

Hey guys, can someone give me a quick rundown on what the options in HQPlayer does? There's so many filters and upsampling/downsampling bits that I don't know where to start!

[Snoopy8]

@Stereophilus Clay did try the Singxer and it was not compatible with the Amanero and abandoned that project. He also mentioned that the Singxer was poor quality.

 

13 minutes ago, Suopermanni said:

EDIT: By the way, I'm getting some weird playback issues occasionally on my WINDOWS 10 PC in that at times, JRiver will refuse to play my music saying the hardware doesn't support its standard rate even though I know it does. 

Did you use the Amanero driver?  Also, you may have to use DoP?

[Suopermanni]

Yes, first thing I did when I connected the DAC was install the win10 version of the driver! And no, surprising when using DSD, I never had to use DOP.

[Gieseler Audio]

Make sure in JRiver you select

“Combo 384 ASIO “ as the output device.

Output encoding to “none”

Bistreaming to “DSD”

[bhobba]

1 hour ago, jermaink said:

The Singxer F1 does not have the exact same pin layout as the Amanero board as originally thought and isn't a direct substitute for the Amanero, so a Singxer F1 based Groß DAC is unlikely as it would require a significant redesign.

 

Clay is going to be building these for a while so it will not happen quickly.  But Clay may take the time out eventually to do a Singster version - maybe when a new version of the DAC chip is released.

 

Thanks

Bill

[Snoopy8]

2 minutes ago, bhobba said:

 

Clay is going to be building these for a while so it will not happen quickly.  But Clay may take the time out eventually to do a Singster version - maybe when a new version of the DAC chip is released.

 

Thanks

Bill

Given Clay's comments about the quality of the board, I would be surprised it is still in consideration!

[Stereophilus]

18 minutes ago, bhobba said:

 

Clay is going to be building these for a while so it will not happen quickly.  But Clay may take the time out eventually to do a Singster version - maybe when a new version of the DAC chip is released.

 

Thanks

Bill

I didn’t mean to derail the owners thread.  Also, I have no particular interest in the Singxer version.  I just wanted to make sure Bill’s version was indeed the amanero version.  I can’t wait to try it up against the Mola Mola DAC.  Out of interest, knowing the DAC has a good digital volume control, albeit stripping bits at lower levels, what is the thought regarding using a preamp vs going DAC direct?

[Snoopy8]

41 minutes ago, Stereophilus said:

Out of interest, knowing the DAC has a good digital volume control, albeit stripping bits at lower levels, what is the thought regarding using a preamp vs going DAC direct?

Am using DAC to powered speakers with volume bypass disabled, just in case it was accidentally set and potentially blow up speakers.  For pre pro owners, volume bypass can be enabled, which is supposed to slightly improve the sound.

 

I favour a simpler setup but I suspect that majority of owners are using a pre pro?

[bhobba]

1 hour ago, Stereophilus said:

Out of interest, knowing the DAC has a good digital volume control, albeit stripping bits at lower levels, what is the thought regarding using a preamp vs going DAC direct?

Clay needs to comment on that - I have something in back of my mind he is using an internal 256 step analogue volume rather than digital.

 

But I can tell you my experience.   Unless you have a particularity good pre the direct is better.   If you have a good pre then using that can make a surprising difference.   Mike commented on that here:

There are others I have heard doing similar things like the AR10.  They all have one thing in common - they are not cheap.

 

Anyway trusted Mike enough to get a BHK Pre.  Will be checking exactly what it does with the Grob.  I am praying it isn't as Mike says - would love to sell it and get some money back.   But I suspect unfortunately it will be as he says - it often is.  Of course I have checked it with the DS and Mike was right.  The comparison between the DS and Grob was with that pre.  Will check it with and without the pre when the Redcloud comparison is done early in the new year.  

 

It will be at Mikes or Rawls - if anyone wants to join us drop me a line.  Remember though Mike can't comment if he is there since he sells both it would be improper to do so - the most he can do is arrange for those interested to hear both.

 

Thanks

Bill

 

Edited December 24, 2017 by bhobba

[Addicted to music]

4 hours ago, bhobba said:

Clay needs to comment on that - I have something in back of my mind he is using an internal 256 step analogue volume rather than digital.

 

 

Yes he does with this statement because I'm sure he's using the AkM attenuation feature that has 256 step in the digital domain not analog.

[Gieseler Audio]

Hi guys,

OK just clearing up a couple of technical points.

All Gross DAC’s use the Amanero USB board & will continue to do so.

I did purchase a Singxer F1 & spent quite a bit of time trying to make it work in a Gross but in the end gave up.

 

1. Not true pin for pin compatibility so owners could never just swap out the Amanero for the F1.

2. The F1 requires quite a bit of modifying to fully power it from a seperate low noise PSU like I do with the Amanero.

     Also doing that would require hard wired cables between my main board & the F1 which is very messy & totally defeats the    

     the neat plug in installation like the Amanero uses.

3. Firmware  updates/customisation & support. The F1 is very weak in this area vs the Amanero which has regular updates,      lots of custom options including a special AKM version.

4. Build & parts quality are definately a step down on the Amanero.

Phew! A bit of mouthful but that pretty well sums it up.

 

Antenuation/volume control system in the Gross DAC.

It is totally digital & uses the built in antenuator in the AK4497 chip.

Now this does cause bit stripping (throwing data away) but due to the 32 bit architecture of the chip you need to be at fairly low levels before you begin to notice any sound quality drop off. If you have high efficiency speakers & do a lot of late night listening probably not a good idea.

 

Direct power amp connection considerations.

Due to the simple transformer output stage on the Gross it does end up with a higher output impedance than a regular active solid state setup which most DAC’s use. It is around 500 ohms so not ideal in driving a power amp with a low input impedance.

eg <10k. 

Tube based power amps normally have very high input impedance so it is ideal with those. 

Also there are plenty of Solid State power amps with >20k input impedance so it would be fine with those as well.

It is a tough call but at the end of the day you really need to test it both ways with your own gear & see what sounds best.

As Bill points out the direct power amp connection can work very very well & for the record that is what I use in my home system.

 

well guys I hope that clears a few things up 

gotta go  -  Santa time!

 

 

Edited December 24, 2017 by Gieseler Audio

[Snoopy8]

3 hours ago, Gieseler Audio said:

Also there are plenty of Solid State power amps with >20k input impedance so it would be fine with those as well.

Thank you Clay (& Merry Christmas!). That explains why the Groß DAC works so well with my SGR CX3B's which has an input impedance of 47k.

[Suopermanni]

Ahha, so that's a possible reason I felt my system sounded better when playing on higher volumes! Anyway, I now testing the Gungnir Multibit with Gen 5 USB versus the GroB with its Amanero board. I'm assuming nothing much will change.

[bhobba]

On 24/12/2017 at 8:06 PM, Suopermanni said:

Hey guys, can someone give me a quick rundown on what the options in HQPlayer does? There's so many filters and upsampling/downsampling bits that I don't know where to start!

Just use the Polysync Filter and upsample to as high as your computer will allow.  Mine wont go past 352k which is DXD.

 

Thanks

Bill

Edited December 30, 2017 by bhobba

[Guest scumbag]

On 26/12/2017 at 9:35 PM, Suopermanni said:

Ahha, so that's a possible reason I felt my system sounded better when playing on higher volumes! Anyway, I now testing the Gungnir Multibit with Gen 5 USB versus the GroB with its Amanero board. I'm assuming nothing much will change.

If you are using a software player that up-samples to a higher bit-rate before applying volume attenuation then the decimation won't be necessary in the DAC. JRiver, Roon do that (I think Roon upsamples to 64bit and JRiver goes to 32bit. HQPlayer ans others I'm sure would also do this. 

If you do need "deep" attenuation and want to do it in the analogue domain then perhaps something like the Lightspeed Attenuator would work here too.

 

Edited January 2, 2018 by scumbag