HOLO Audio Spring DAC - R2R DSD512

[Bimmer100]

1 hour ago, Miska said:

 

That is always a risk, especially in an OS like Windows. Since Windows decides to for example change the default audio output device on it's own. I usually direct default sounds to the mainboard audio so that notification sounds and "normal applications" don't try to play sounds to the DAC. Plug in a USB audio device and Windows usually switches it to be the default audio device without asking.

 

With embedded operating systems / players it is less risky, since they are single purpose systems with no emails applications or similar.

 

But this goes also into gain matching category. Since pre-"amps" are nowadays actually pre-"atts", it is important for signal fidelity to match gains such way that there is not too much back and forth attenuation and gain. It is pretty pointless and damaging to first attenuate signal a lot just to amplify it even more in next stage. Still, even with pre-amp/att you can optimize signal fidelity by setting it's volume control as high as you would ever listen and then attenuate from there using digital volume control. So you'd never actually touch the pre's volume at all.

 

Sure! I agree with this of course.and know where you are coming from. (Talking about the last part of your response and preamps and digital volume....

 

but the first part of your response... most of our customers use operating systems like windows 10 so the reality is what it is. The whole Os debate could go on and on. But what works for one person may not work for the next. I still recommend a preamp to anyone. As long as it’s a good one. Since many preamps are pretty darn poor quality and degrade the signal.  But some preamps do not.

hopefully that anyone who is looking to use the May in their system will realize a quality preamp is still highly recommended in most cases... (not all cases) 

 

personally I have been most excited for the serene preamp/headamp for my own reasons. But that amp will drive susvara’s incredibly well with a lot of headroom. And also have a very high spec’d analog relay based volume control. And share the same chassis as may, same display. And planned to have many output on front for heapdhones, and plenty of inputs to make  for a very capable preamp for high end full featured loud speakers setup. 
 

 

on another note, for those who are into vinyl.... the KTE LCR-1 MK4 is new and looking for some reviewers. Imo one of the exciting products for myself as i spend a lot of time with my japanese vinyl collection. I listen to as much analog as I do digital. Sure the May sounds better but no replacement for being hands on with a nice gatefold album, cool inserts and the feel of vinyl!

 

[barrows]

49 minutes ago, Bimmer100 said:

Correct me if I’m wrong but when I think of small compact setup I think of a small bookshelf speaker system with maybe an integrated class D amp/dac all in one. 

Yes, you are wrong, if I understand your point correctly.  I have been an audiophile since high school, raised by an audiophile Father and Uncle, and I have worked in the Industry for the last 20 years.  I am interested in best possible sound quality and my system can be seen in my Signature (maybe not if you are viewing on a phone?)

 

But, i do not believe having 5 or 6 boxes, masses of cables, and more complexity leads to the best sound quality.  I believe in the principle of make it as simple as possible, but no simpler than necessary.  My rack has 3 shelves and contains a streamer (the server and Network gear is another part of the house, it is important to keep the noisy commercial computer gear away from the audio system) with a single USB output capable of delivering Native DSD up to 512, and up to to 768 PCM.  A full size DAC with volume control is on another shelf, and an amplifier on the bottom shelf.  Speakers are medium sized, 46" tall floor standers, capable of producing high SPLs filling my medium sized living room and there is a JL 12" sub which fills out the bottom octave.  I have no vinyl set up, as I do not have the time to deal with vinyl (although I have been collecting LPs again, with the thought that maybe, when retired I'll get 'table set up again).

 

I have had a few high end DACs through here recently, Bricasti, PS Audio DS, Resonessence Audio, etc, but I normally use DIY DACs.  All have had built in volume controls.  I match the gain of my system so that I do not have to use a lot of digital attenuation.  I used to have an Ayre preamp, but once i figured out how to make the DAC outperform the system with the preamp in place, I ditched the preamp.  Having a DAC which can drive an amplifier directly does not usually require adding anymore than the volume control itself, as most DACs these days have output stages that are the equal of any preamp, and most amplifiers are pretty easy to drive.  Of course those with analog sources need a preamp, so there is no choice there.

 

Oh yeah, I live in a rural area on 3 acres, so if I want to play TOOL (or Anne-Sophie Mutter) at 2 AM at 90 dB average levels, i can, and often do.

[Bimmer100]

And this is why I don’t post on forums. Everyone has an opinion. And I’m not here to fight over who is right or wrong. 
That being said. I respect your opinion. And you can disagree with mine too. However I’m not going to debate it with you either 

 

also adding: I was speaking “in general” and not literal as in all cases. So don’t take it literally. I’ll keep my opinion to myself entirely here forward! 

[audio.bill]

8 minutes ago, Bimmer100 said:

And this is why I don’t post on forums. Everyone has an opinion. And I’m not here to fight over who is right or wrong. 
That being said. I respect your opinion. And you can disagree with mine too. However I’m not going to debate it with you either 

 

also adding: I was speaking “in general” and not literal as in all cases. So don’t take it literally. I’ll keep my opinion to myself entirely here forward! 

No Tim, please don't do that... It's great to have your active participation here and your opinion has value to others! There may be some disagreement along the way but that's all a part of how we can continue to learn from each other's experiences. I appreciate your valued perspective which of course will include some opinions along the way.

[Bimmer100]

1 hour ago, barrows said:

 I believe in the principle of make it as simple as possible, but no simpler than necessary.

What necessary for you is different for the next guy
i cannot stand when one had such a strong opinion it must trump all others.

seriously. Lighten up man  

me saying “correct me if I’m wrong” was not meaning literally tell me all the ways I’m wrong justify all the ways you are right. It’s a nice way of saying. In general I see compact systems this way however not on all cases....  your opinion is legit as mine is too.  I won’t justify mine. It’s ok as is.

 

anyhoooo. 
 

2 minutes ago, audio.bill said:

No Tim, please don't do that... It's great to have your active participation here and your opinion has value to others! There may be some disagreement along the way but that's all a part of how we can continue to learn from each other's experiences. I appreciate your valued perspective which of course will include some opinions along the way.

 

Thanks for this, but please understand I’ve got a lot of my plate and love to jump in here and there to help answer questions like Barrows assuming/guessing/wondering what we’re using specific caps for in circuit. They are for the power supply so it’s great to get clarification on things so everyone knows. 

 

and sharing the exciting new third party measurements of the KTE May which definitely should vary from ASR’s measurements considering they measured a Level2 May.

 

and Atomic bob @sbaf also is measuring a KTE Spring2 as well. Those might be up in the near future too.

 

i take it all with a grain of salt but really have a sore spot for when forums turn into a right and wrong debate. It should be focused on mostly positive contributions from many users, all while having a mutual respect for each other’s opinions. Not to forget that audio or the perception and enjoyment of audio is subjective. And measurebaters focusing on measurements as a primary way to enjoy music will inevitably continue, but that is truly one side of the coin. I hope that most will find the May has it covered on both sides. It sounds as good as the measurements show. And maybe you can doubt the results, but don’t take it out on me. We have third parties do it for a reason. 
 

anyhow, I’ll chime in once in a while. But not going to entertain debates about whose opinion is right. Imo we both are right.... so there!

So so Sorry! But my opinion can be shared off of forums. It’s better that way. In my opinion  

[barrows]

11 minutes ago, Bimmer100 said:

i cannot stand when one had such a strong opinion it must trump all others.

 

Hi Tim, I think we have a mis-understanding here, sorry for that.  When i said you were "wrong" I was replying directly to this comment:

 

1 hour ago, barrows said:

Correct me if I’m wrong but when I think of small compact setup I think of a small bookshelf speaker system with maybe an integrated class D amp/dac all in one. 

 

Where it appeared to me that you were suggesting that my system, and what I am trying to achieve with it, was someone how not a serious audio system.  All I was attempting to say, was that no, I have a serious audio system and I am serious about sound quality.  Apparently I did not communicate this well enough.  

 

Now, as far as the use of a preamp is concerned, for you, with multiple sources, a preamp is a necessity, for me, with a system completely focused on digital music playback only, indeed, I have no need for a preamp. In my experience, as long as the DAC output stage can adequately drive the input stage of the amplifier, the addition of a preamp can only add noise and distortion, resulting in lower fidelity.  As mentioned, I tested this here very carefully, with a quite capable preamp (Ayre K-5 xe-mp), so my opinion on this is a result of my actual testing.  Of course this is my experience, and my opinion resultant from my experience, and of course, you are welcome to have a different opinion.  I would love to debate this topic with you and anyone else interested in another thread, but not here where we should be talking about Holo Audio DACs.

 

Thank you for answering my technical questions.  And congratulations on the May DAC, it looks like a very impressive product.

[emcdade]

I think there may be a few (many) statements being "lost in translation" here.  🙂

[Superdad]

4 hours ago, barrows said:

Oh yeah, I live in a rural area on 3 acres, so if I want to play TOOL (or Anne-Sophie Mutter) at 2 AM at 90 dB average levels, i can, and often do.

Oh come on Barrows, we know that you play TOOL at a LOT louder than 90 dB! 

[StreamFidelity]

9 hours ago, barrows said:

@Miska, It is good to hear that you feel HQPe is pretty reliable in this regard to volume control stability

 

I can confirm that. With a sound engineer I heard for comparison with the preamp section of a T + A PA 3000 HV. What can I say? The digital volume control of the HQPlayer was clearly superior.

 

However, it is always recommended to use a dedicated Audio PC for this. Nothing else runs on my audio PC except the HQPlayer. My Roon Server runs on the Control PC. I activated a volume limit in Roon itself to avoid destructive noise.

[barrows]

Thanks for that response @StreamFidelity, for sure I would be using a dedicated server just for music playback with HQPe, running SGC's Sonic Orbiter Linux based OS, but I would want to run Roon on the same machine.  Of course I would be using  NAA and the iPad for remote.  Maybe I could get away with just the software volume control... 

[LowOrbit]

And of course HQP lets you configure a max and min attenuation value so you even if mis-set you can have the relative peace of mind that it won't ask you system to go full scale and fry transducers, amps or ear drums.

 

Like Barrows I tend to use DIY DACs (and amps). My current favourite is a DSC1 dsd converter so no built-in attenuation. I have tried many varied approaches to attenuation and agree that only a very well engineered preamp can get close to matching the transparency of HQP attenuation. So, in most single source setups, if you run a good software volume control that should be the best, simplest and most economical approach.

 

I have some interest in the e.g. Metrum approach of changing the reference voltage in the dac as a means of controlling signal level, but I suspect that only works well over a relatively small range.

 

 

[4est]

3 hours ago, LowOrbit said:

And of course HQP lets you configure a max and min attenuation value so you even if mis-set you can have the relative peace of mind that it won't ask you system to go full scale and fry transducers, amps or ear drums.

 

Like Barrows I tend to use DIY DACs (and amps). My current favourite is a DSC1 dsd converter so no built-in attenuation. I have tried many varied approaches to attenuation and agree that only a very well engineered preamp can get close to matching the transparency of HQP attenuation. So, in most single source setups, if you run a good software volume control that should be the best, simplest and most economical approach.

 

I have some interest in the e.g. Metrum approach of changing the reference voltage in the dac as a means of controlling signal level, but I suspect that only works well over a relatively small range.

 

 

OT sorry. Within the range of the shift register voltages, this might work for the DSC builds just by varying the 3.3/5v power rail. And yes, it would be a smaller range, but would keep things super simple too. I like simple. This could keep the output down to a point where it wouldn't damage anything by using software attenuation. I happen to run my DSC build into a transformer volume control directly. Win win!

[emcdade]

I would have no problem using HQP's digital volume control......if it fooled me with a big old volume knob and a readout on the DAC!

That's the part I need more than a resistor ladder, tactility!

 

[barrows]

I am fine with using HQP volume control, as long as there is no risk of it going to full scale via a computer software glitch.  In fact I would prefer such as a digital VC with good implementation is superior to any analog VC, and also means a little less noise in the DAC (most resistor ladder volume controls switched by relays, use a microprocessor to handle controlling them).

[ericuco]

4 hours ago, barrows said:

I am fine with using HQP volume control, as long as there is no risk of it going to full scale via a computer software glitch.  In fact I would prefer such as a digital VC with good implementation is superior to any analog VC, and also means a little less noise in the DAC (most resistor ladder volume controls switched by relays, use a microprocessor to handle controlling them).

I have been using a Goldpoint passive preamp for VC of Holo Cyan (DSD only) but you guys inspired me to try the HQP VC. The Cyan is now connected directly to my Ncore amps (Goldpoint removed).
 

Really liking what I am hearing so far.

 

I set the the limits on the HQP volume at -20 dBFS max & -60 dBFS min. Right now volume is at a comfortable -38 dBFS which is about 1 o’clock position of HQP knob although I am using Roon to adjust volume.

 

 

[Miska]

7 hours ago, emcdade said:

I would have no problem using HQP's digital volume control......if it fooled me with a big old volume knob and a readout on the DAC!

That's the part I need more than a resistor ladder, tactility!

 

You can actually get such as external HID devices. Not specifically the old style traditional, but rotational encoder one that you can find on newer amps (optical encoder that rotates forever to either direction). This reduces also risks of accidental volume turns that can more easily happen when operating volume with a mouse or similar device. Mac is just a bit limited on such, Windows and some Linux desktop environments should be better.

 

The readout on DAC display is missing though. But HQPlayer Client has readout on the main view (and of course main window of HQPlayer Desktop).

 

[Superdad]

7 hours ago, barrows said:

I am fine with using HQP volume control, as long as there is no risk of it going to full scale via a computer software glitch.

 

Well the scary part of using the HQP volume control is that it allows you to go around the bottom of the "horn."  That is, if you turn it all the way down, the GUI allows you to accidentally keep going counter-clockwise--right to max volume!  I truly wish Jussi would fix that at I can not see any useful purpose served by allowing such.

[Miska]

6 minutes ago, Superdad said:

Well the scary part of using the HQP volume control is that it allows you to go around the bottom of the "horn."  That is, if you turn it all the way down, the GUI allows you to accidentally keep going counter-clockwise--right to max volume!  I truly wish Jussi would fix that at I can not see any useful purpose served by allowing such.

 

The knob comes from the GUI toolkit and I'm not too fond of trying to modify the GUI toolkit. But remember to set the max volume in Settings to something reasonable!

 

However, the server knob shouldn't get used much these days, volume should be controlled from clients such as HQPlayer Client. There you don't have such issue.

 

[asdf1000]

On 2/21/2020 at 4:20 AM, Bimmer100 said:

Once the serene comes out it would be an incredible matching setup with the finest components for preamp/and headamp

 

Hi Tim (if you're still here).

 

I've been looking for a Holo DSD DAC but with headamp output (analogue volume control).

 

Is this what Serene will be? Or no DAC inside Serene?

 

 

[asdf1000]

I know @Miska has shared measurements showing Holo Spring2 measures best with DSD256 input.

 

Someone has shown similar measurement showing it measures best with DSD256 input:

 

https://www.audiosciencereview.com/forum/index.php?threads/wolfx700-measurements-of-holo-audio-spring-2-lv2.10678/post-296723

 

It's always nice to see additional verification.

[Bimmer100]

58 minutes ago, asdf1000 said:

 

Hi Tim (if you're still here).

 

I've been looking for a Holo DSD DAC but with headamp output (analogue volume control).

 

Is this what Serene will be? Or no DAC inside Serene?

 

 

 

serene will be totl or flagship preamp/headamp. Same form factor as spring/spring2/May dac chassis and designed to pair perfectly with these products. It will be an absolutely epic preamp/headamp with tech similar to azure yet many improvements of course. 
 

[asdf1000]

22 minutes ago, Bimmer100 said:

 

serene will be totl or flagship preamp/headamp. Same form factor as spring/spring2/May dac chassis and designed to pair perfectly with these products. It will be an absolutely epic preamp/headamp with tech similar to azure yet many improvements of course. 
 

 

Thanks!

 

No DAC inside Serene , correct?

[asdf1000]

Hi @Miska

 

Is the Spring1 and Spring2 based on your open DSC1 Open Hardware design?

 

Did the designer contact you during design with questions?

 

Or even when you opened your unit you can see it is based on your design?

[Miska]

8 hours ago, asdf1000 said:

Is the Spring1 and Spring2 based on your open DSC1 Open Hardware design?

 

Did the designer contact you during design with questions?

 

Or even when you opened your unit you can see it is based on your design?

 

I wouldn't say based on design, but based on idea, I think both use similar approach, like Denafrips and T+A too. But all these are different enough designed from ground up not to be called based on my design even if based on the same idea.

 

So you need to differentiate between actual design and principle of operation.

 

[Superdad]

12 hours ago, asdf1000 said:

Is the Spring1 and Spring2 based on your open DSC1 Open Hardware design

4 hours ago, Miska said:

So you need to differentiate between actual design and principle of operation.

Shift-register DAC design can be executed in a number of ways (and to different levels), including choice to do the FIR in analog or digital domain.