Linear Phase filter settings. Topping: How we (ASR) can help?

[Ron Texas]

All of these DAC chips have options the builder can either "hardwire" or make adjustable. The CS4398 chip is an older design with fewer options. I'm wondering if the harshness I hear is due to the chip or it's implementation. I was also running it at relative high volume with a Crown Amp which requires 1.4V for full output. It might sound better (avoid clipping) If I turned up the sensitivity on the Crown. Something to try next week.

 

[solderdude]

I have the FiiO X3-II which uses the exact same chip and has both filter settings user selectable.
I would say it sounds buttery smooth in both settings, just like my FiiO X3 (original, but that one only when 0dBFS is not reached) and all the other DACs I have.
There is absolutely no hardness to the sound in neither setting.
That is, unless the hardness is in the recording.
In that case the 'hardness' is accurately reproduced.

I am not saying you or any other folks do not hear hardness, I honestly cannot say.
One thing is certain to me ... it is not the DAC chip nor both filter settings that are causing any perceived hardness.
I don't own a D30 so cannot compare.

 

[sajunky]

No, that's not what I said... so I will try to explain again

Topping just 'hardwared' the DAC chip so it uses the linear-phase filter present in the DAC chip.
It is not their 'own' filter, tailored to their personal wishes or 'beliefs' nor is the other filter that is available in the DAC chip user-selectable.

As you quoted there are two settings for this filter: fast and slow roll off (which in this case is fast rolloff for better measurement result, are there?). In addition chip can work with single speed, double speed mode, etc.... There are number of combinations of chosing a mode for the same sampling frequency. Changing the mode is changing filter characteristics The datasheet refer to the AN48 for designing the analog output filter that should care about total amplitude and phase response. D30 has an ideal amplitude response, probably on expense of phase (yes, they could mess up with phase) and group delay.

 

[SIY]

If you don't understand simple things like "what is a ground loop," I'd probably avoid trying to interpret datasheets.

 

[sajunky]

If you don't understand simple things like "what is a ground loop," I'd probably avoid trying to interpret datasheets.

That is completely off topic. You may agree or disagree with my understanding of ground loops, but you shouldn't bring it here.

 

[SIY]

You either lack understanding of many topics, including this one, or you understand well and are just looking for attention.

I have my own opinion, but either way, I do not encourage anyone to engage you in a discussion and expect it to be either a useful one or an honest one. I'm particularly looking at you @solderdude since you are much nicer, trusting, and more patient than any of us deserve.

 

[BDWoody]

That is completely off topic. You may agree or disagree with my understanding of ground loops, but you shouldn't bring it here.

Of course it's relevant...It's about your rapidly declining credibility to gather support for a problem that so far only you believe exists.

You are trying to swim in the deep end with people who dug the pool, when you are still in kiddie pool knowledge.

Listen to these people. You aren't as smart or as clever as you clearly believe.

Cheers.

 

[solderdude]

As you quoted there are two settings for this filter: fast and slow roll off (which in this case is fast rolloff for better measurement result, are there?). In addition chip can work with single speed, double speed mode, etc.... There are number of combinations of chosing a mode for the same sampling frequency. Changing the mode is changing filter characteristics The datasheet refer to the AN48 for designing the analog output filter that should care about total amplitude and phase response. D30 has an ideal amplitude response, probably on expense of phase (yes, they could mess up with phase) and group delay.

fast roll-off is for better performance and thus also better measurements. That's why it is selected in the D30. Not to rob owners of optimal sound and mislead them.

The sampling frequency mode is determined by the input sampling frequency not something that is 'set' by Topping to manipulate sound for better measurements.
Of course, with a higher sample rate the filter also has to change with it. All DACs that support multiple sample rates do that.

Yes, one can f-up the analog post filtering stage. That one is fixed frequency, not steep and based on the highest sample rate cut-off frequency or just below.
It does nothing in the audible range so can't mess up phase and group delay when they adhere to or slightly change the, by Cirrus, suggested filtering.

There are lots of things that can be messed up in any design.
A high susceptibility for ground loops is one of them.
A poor USB implementation, poor signal handling, poor layout, poor wire routing, incorrect choice of opamps, incorrect decoupling of certain chips to name but a few.

The first one I mentioned is not tested by Amir but some complain about this so may be a valid complaint, but is only an issue IF you have a (bad) groundloop. There are solutions for this.
The other aspects are visible in one way or the other in measurements. These look good to me given the price point so don't see many things there that are wrong.

It's you that needs to prove something is 'wrong' with (your?) D30 or your setup it is in. No point in whining about it and regurgitating the same subjective babble.

 

[solderdude]

I have my own opinion, but either way, I do not encourage anyone to engage you in a discussion and expect it to be either a useful one or an honest one. I'm particularly looking at you @solderdude since you are much nicer, trusting, and more patient than any of us deserve.

It's almost Zalive all over again is it ?
I am not yet reaching my boiling point otherwise there would be animated gifs.
In most cases I reply in a more elaborate way because I know there are folks that also adhere to a similar line of thought.
Maybe something of what I write may be of help to them.
I understand your frustration though.

Certain people you can tell/teach something. Others are stubborn. The only way to get them to change their minds is to coach/push them to test certain things themselves.
It's unfortunate he does not want to play/do that.

 

[BDWoody]

It's almost Zalive all over again is it ?
I am not yet reaching my boiling point otherwise there would be animated gifs.
In most cases I reply in a more elaborate way because I know there are folks that also adhere to a similar line of thought.
Maybe something of what I write may be of help to them.
I understand your frustration though.

Your patience is truly exemplary...

As you say...others follow along. Good reminder.

Just feels more and more like a troll...