Topping D90 great but question future

[ambre]

2 hours ago, LowOrbit said:

AKM 44XX dac chips can be configured so that when DSD input is detected, the data is sent directly to the output modulators. This removes internal dac decimation/upsampling/filtering from the reproduction of dsd, a purer options especially if you do DSD in software (e.g. HQPlayer etc).

 

 

Disable pre-amp in Topping 90 and direct Dsd is available😍

[ambre]

5 hours ago, barrows said:

As for the AKM chips, they have “direct DSD mode”, which bypasses all of the DSP, oversampling, and the delta sigma modulator, and just sends the incoming DSD stream directly to the conversion stage.  THis approach sounded fantastic to me with the D-90 and DSD 256.  Best performance with the AKM 4499 is with DSD 256 as far as I am concerned.

Hi Barrows,

I own also a Topping 90 feeded by the Allo Usbridge Signature with Uptone IsoRegen.

Using always Hqplayer ( poly-sinc-ext2 and ASDM 7 or ASDM5EC)  for upsampling DSD 256 of 512 depending which filter I use.  

Can you explain why at DSD 256 is better? Is that in terms of (ASR)  measurement  and/or by listening?

 

Very best regards, Andreas

 

[ambre]

19 minutes ago, w1000i said:

it measures better with 256 instead of 512

I have asked Barrows for an explanation especially i don’t hear any kind of difference and for some music Dsd 512 sounds better. At the end it handles Aboutaleb SQ.

[ambre]

4 minutes ago, barrows said:

Hi Andreas.  I looked at the data sheet for the AKM 4499 chip used in  he D-90.  The data sheet has specifications for the chip's performance with different DSD rates, it can clearly be seen that at DSD 256 it performs very well, but that noise noise and distortion actually rise with DSD 512 input.  I have heard Andreas Koch (DSD expert and designer of Playback Designs DAC) discussing different DSD rates, and his point of view is that the "switches" used to convert DSD are not really fast enough to cope perfectly with sample rates as fast as DSD 512, so this may be why the AKM 4499 chip performs better with DSD 256 (the converter tech in the AKM 4499 is a switched resistor converter).

 

See section 8.1.2 of the attached data sheet for details. 

AK4499_Feb2019.pdf 1.7 MB · 2 downloads

Hi Barrows,

many thanks for this kind of explanation.

I don't have a technical background but understand what you are pointing.

 

I (my real life)  don't hear differences of SQ maybe because I am using another kind of filter  to lower CPU capacity. Especially when using the EC filtersmy Mac Mini I7 (6 Core)  sounds....  like an Apple hairdryer.

 

But the Topping 90 is a real bargain compared to my previous dacs and sound much more detailled resp. especially in combination with Uptone ISORegen, EtherRegen and the very nice Allo UsBridge Signature. 

 

Best regards, Andreas 

[ambre]

On 5/14/2020 at 8:37 AM, barrows said:

I am not sure I remember...  I think it was a 250 mA maybe?  Anyway, the fuse is marked.  Topping uses a dirt cheap glass body fuse, even a good quality Littlefuse ceramic body model would likely sound better.  

It is definitely a 5 x 20 mm size, slow blow.

I have asked Topping a few weeks ago about the specs of the Fuse.

 

It is fastblow, 0.2A 5x20mm. 

So not a Slow Blow.

 

Like Barrows I will try at short notice also the attached fuse.

About why or is measurable etc. is and remains on ongoing debate. But I will trust my ears and especially my family If we hear really a difference and/ or improvement. But it is  a very high price😇

[ambre]

7 hours ago, Blake said:

 

So you say the D90 is a "perfect" DAC and the upcoming Topping preamp will be the cleanest in the world.  As long as you believe this stuff, I suppose that is all that matters.  Enjoy!

 

9 hours ago, w1000i said:

 You mention the peramp in D90, and FYI Topping is about to lunch P90 as preamp and going to be the cleanest in the world alongside A90 a headphone amplifier.

That is indeed a statement that cannot be underpinned.

 

But  like Barrows it is a giant killer. but at the price, heck, it is a no brainer. And maybe with a better fuse ???

 

Best Regards, Andreas

[ambre]

13 minutes ago, barrows said:

Wow!  That is really, really weird.  Typically, in every product I have ever been aware of over my 40 years of being an audiophile, I have never heard of any product which used a fast blow fuse for its main AC inlet fuse (fast blow fuses are often used internally in amplifier power supply rails to protect the output devices from burning at clipping).  The reason for this is that most components will draw the most current on the initial power up, because the power supply is entirely uncharged at this point, and the power supply capacitors act like a dead short until they are charged, hence there is a very "fast" and large inrush current, briefly; a slow blow fuse allows for brief periods of over current without blowing..  I am very surprised a 200 mA fast blow fuse could even survive as an AC input fuse in this DAC.

Sometimes "Audiophile" fuses blow more easily than their standard counterparts, probably because the Audiophile fuse makers err on the side of safety.  I have seen "Audiophile" fuses of the correct blow when they should not have, and sometimes it is necessary to raise the fuse value by one step to keep them from blowing when they should not.  Given the expense of these "Audiophile" fuses, i ma not sure I woudl put a fast blow, 200 mA, Synergistic Orange in this DAC, as I woudl be afraid it might blow at power up.  One might consider upping the value a little if they are going to use an "Audiophile" fuse.

 

Main AC input fuses basically protect the device from further damage if there has been an internal problem, they should only burn when there is an internal problem (a broken DAC which draws too much current, typically some kind of short somewhere in the circuit).  The fuse then fails to protect both the component from further damage, and from the possibility of catching fire.  I would not advise to change the fuse value recommended by Topping though...  but I know what I would do here.

Hi Barrows

Ok this make a lot of sense. Will contact  again Topping about this issue.

Ps. I am not willing to spend €150 + en it blows within a few minutes.

 

Please see attached the reaction by Topping.

Regards Andreas

[ambre]

1 hour ago, barrows said:

I am not trying to deny that they use a fast blow fuse for AC input, I just find such spec very, very curious if it is so.  Note that a slow blow fuse is typically marked with a "T" designation on the endcap (the "T" denotes time delay).

 

If one does not want to spend a ton of cash on an Audiophile fuse, a high quality standard industrial part should still be a nice upgrade of the cheap fuse Topping uses.  I would recommend a ceramic body fuse from Littlefuse of the appropriate rating, these are around $1.50.

Hi Barrows,

 

Already sent an rmail to Topping for clarification. May be a mistake?

Ps. I didn't removed the fuse yet may be the printing (if readable) gives the solution.

 

Do you still have the old fuse? What can you read on it ?

 

Regards, Andreas

[ambre]

3 hours ago, barrows said:

Umm, that is exactly what I said???  the fuse will only blow (if correctly specified) if there is already damage to the device.  Primary purpose of the AC line is to prevent fire, as we both stated.  The secondary purpose is to prevent further damage to the device:

For example:  If the D-90 were to develop a shorted output stage component, it would then draw excess current, which, primarily, could cause the unit to catch fire.  So primarily the fuse protects against that "large" problem.  But secondarily, a properly sized fuse will also blow early enough such that it usually prevents further damaged parts in the component.    I am only posting more details for those who may not.

 

But you are mistaken if you are saying most AC line (input) fuses (in audio components) are specified as fast blow.  They usually need to be slow blow so that they do not blow with the higher current inrush at initial power up.  I have never seen a single audio component, be it line level or power amplifier, with a fast blow fuse specified for its AC input fuse before the D-90.

Hi 4est & Barrows, 

 

A lot of discussion and confusion now and not a straight answer yet.

What will it be: Fast Blow or Slow blow? What now is the safest type and functions well?

Please an understandable advice for a laymen.

 

Ps. Barrows promoted the Synergistic Research Orange.  If there is an underpinned measurement, blind test etc.... is a complete other kind of discussion. First of all I will trust my OldEars🤩.But it too costly to blow €155 within a few minutes of time.

 

Ps. In my Shanti Lineair Power Supply as counterpart for the Allo USBRidge they also describe Fast Blow (20mm fuse 500 mili amps Fast blow).🤭 

 

Please see attached today's reaction by Topping. They might also be confused. 🤯

[ambre]

9 minutes ago, barrows said:

You should use whatever type and (fast or slow) and whatever value is recommended/specified by the manufacturer.

Hi Barrows, it was you who questioned the choice of a Fast Blow fuse. Can't handle this way of reacting. Back to the end.

Have a nice evening.

[ambre]

Just now, barrows said:

And I still do, but I am not going to recommend to anyone to use a different type and value of fuse than what the manufacturer recommends.  Please understand this is both a safety and a liability issue.

Ok 🤠

[ambre]

20 minutes ago, OldBigEars said:

 

@Barrows, hate putting the burden on you.  I can only imagine it wouldn't take much to improve on the quality of the standard fuse in the D90.  I took mine out and it's not a premium product.  I tried to read the text scrawled on in - albeit I didn't run around the house to find our magnifying glass, which was lazy - but couldn't figure out the spec on it. The Littlefuse tip looks interesting, although their website is not exactly consumer-friendly.  If I keep my D90, that's a possibility with nothing to lose (once we find out the real, confirmed specs

 

On another topic....power cable.  At about midnight last night I decided to put the original AC cable back, replacing the AudioQuest Blizzard that I normally use with my HD25.  The D90 bass was truly awful - horribly bloated.  Stuck the original cord back in, and voila....so much better. It was hard to stop listening at 1am.

Hi NewBigEars,

Please try dsd 256 with HqPlayer and you will notice where the Topping 90 is designed for and a next step SQ and hires via usb.
Very best regards,Andreas

 

[ambre]

33 minutes ago, w1000i said:

What I understood from Topping designer, some DACs uses passive LPF path for the preamp like SMSL M400. This Gustard has active LPF as per their advertisement.

What does this mean and how can you underpin this kind of statement?

 

Advertsiments are mostly marketing driven

Subjective comparing both dacs is first step and would be nice if this can be underpinned with objectieve measurements and blind tests.

 

Would be great is this manufacture outperforms the imo very good Topping 90 which  supports Direct native Dsd. Just curious and itwould-be a bargain.🌞

 

 

[ambre]

4 hours ago, OldBigEars said:

No disrespect to anyone enjoying their D90's, but after 4 weeks I think I've reached the end of the line with mine.  We've had our good times, and I can see how she would appeal to many.  But I'm not feeling it.

 

Before I pack her up....I'd love to hear any mitigating factors. I've probably put around 120 playing hours on my D90.  Could I expect any further changes in the future? She's definitely mellowed since new, but still has a slightly irritating voice.  I do use the standard USB cord and, of course, the basic fuse. 

 

@Barrows was right about DSD - even 128.  Amazingly wide soundstage and detail.  But I'd question whether it's a pleasing DAC to live with over the long term - there just has to be more refinement out there, without spending silly money. Maybe I'll try an NOS model, such as the Orchid or Troubadour.

With HqPlayer and Ec filters for Dsd 256 / 512 In combination with a powerful pc / imac will give a dramatic jump with thé Topping 90.

 

A realy Top Dac the same as Barrows said. A bargain.
 

 

[ambre]

Roon does’t  equals by far...,,.. HQPlayer4.x imo.
 

Besides the Eq filters there are many other  very nice variants too. Especially in terms of transcients and stage.
 

But you have to replace yr computer first to unlock the REAL potential of Hq player.
 

Besides that I use Allo Usbridge Signature incl. Uptone ISO Regen to clean the signal path and ‘reclock’ the usb signal.

And the Uptone etherRegen which feeds the Allo. That makes anorher lot of differences to my Old ears resp. System.
 

Very best regards,Andreas

 

 

[ambre]

39 minutes ago, OldBigEars said:

 

I've been seriously thinking about the EtherRegen and/or upgrading my mR 1.4 to oR.  That could probably help.

 

 

Uptone Etherregen highly recommended.

ultra rendu + fiber+ EtherRegen is also top notch.🤓