Digital Sample Rate Settings On X1850 Mixer

Hi - I want the best quality sound on my equipment to went into advanced settings on my mixer and found the the sampling rate was set to 48khz. So I changed it to 96khz then for some reason the LED channel level meters on all 4 inputs where flashing in turn on the bottom LED of - 40. At this point the fader trim was at about 12 O’ clock, if I turn the fader trim to zero it does not flash any more but if I turn the fader trim higher than 12’O clock not only does the -40 flash but - 30 as well.

So does anyone know why the LEDs flash when set to 96kHz as the unit is designed to work at this sample rate.

Any thoughts on this.

What are you feeding into it 48 or 96. If your feeding it 48 then its upscaling it which is going to sound crap. Set it to the same as your feeding it for best results

Why would you say it will sound crap ? Because the hardware is too weak to do it well ?

Becauae your trying to upscale a 48 to 96 on the fly. Irs going to clip like a #@%$

Honestly I would not see any benefit for me to use my X1850 in 96Khz mode especially since I would loos some FX, but I would not assume that the sound quality would be affected in a negative way. Would be stupid to provide such a functionality from Denon DJ :slight_smile:

Oh, I just recognise this setting is only affecting the digital audio out. It has nothing to do with the internal signal processing in general.

Screenshot 2022-07-09 at 10.16.04

Thats the max output if thats what you feed in. Anything less will be processed to give that output. Or at least thats my understanding. So if you feed it a 128 mp3 dont expect a magical studio quality sound out … to get that out thats what you have to put in

1 Like

What max output ? If I am setting it to 96khz my digital out will be set to 96khz. The internal signal processing and the quality of the medium you are playing have nothing to do with it. Of course it will not do magic and improve the overall quality of a crappie mp3 file but this is what you get if you connect another device. There is nothing else we should assume if we read the manual of the mixer

Hi everyone.

Thank you all for your input and based on things you have said I will be trying another test of my own on Monday.

The files that I play are varied the newer ones are all Wav hi-res (not that good) plus some rubbish MP3 tracks, however the majority are my own Wav 96 kHz @ 24 bit they was 192 kHz but I scaled them down to match the SC6000 sample rates.

I know if the tracks sample rate is rubbish to start with then there is nothing you can do to improve it but as I say most of my tracks are 96 kHz @ 24 bit.

But regardless of this I still can’t see what this would have to do with my issue of the LED channel level meters on all 4 inputs flashing in turn on the bottom LED of - 40 just because I set the output to 96 kHz. I have read the manual and there is nothing in there about this.

Thanks - Keith

??? If your feeding a low quality low resolution file in of course its going to upscale it internally to feed the 96 output. That’s how i understood the manual

To sum it up a little bit what I wanted to say.

  • SC6000 is dealing with the upsampling and not the X1850

  • SC6000’s Digital outputs are fixed to 96 kHz/ 24 bit

  • Internal processing sample rate for X1850 is not specified from Denon DJ but I assume its 96 kHz

  • What we can control in X1850 - “Advanced audio” is only the sample rate used for the digital audio signal and not for internal signal processing.

Sounds this logic now ?

Like @DJKeith said he would like to get our feedback on the LED issue in 96 kHz mode. I did not get this problem when I switched to 96 kHz (output mode) once. I would assume the best would be to experiment some more with input selection or to open a support request and to await what they say.

Hi Aquadics The test I hope to do tomorrow if time permits will show if there is a fault or not. I have already asked Denon’s support InMusic via the place I bought the equipment from this question as if I open a new ticket you are looking at 6/7 days for a reply but the dealers have a direct line. I will post the outcome once I know more. - Keith

1 Like

The control you have over sample rate on the Prime X18xx mixers is over the internal sample rate it runs at, which it will convert every SPDIF input into and for which the mixer SPDIF output will also match.

I’ve sent old Pioneer CDJ 44.1khz SPDIF into the X1800 without issues both at 44.1 and 96 on the mixer. I preferred matching the rates on the X1800 with lower bitrates, but for some reason at 96khz there seems to be some odd trade-offs besides just losing a few effects when sending 96khz into the mixer set to 96. I don’t think the difference in sound is as wildly different between the rates as on the X1700, though, where it was obvious when the rates were matched and you were getting by the numbers but very accurate performance, and when you were doing the nifty (edit: not-SHARC) interpolative upsampling that clearly was adding pleasant, euphonic things to the sound beyond what you input. The X18xx mixers are kind of dry, grainy, and boring sounding already, other than their killer low-end, and their SRC is equally boring, but at least by the numbers. The X1800 tests perfectly fine on both TruRTA and RightMark that I could tell, and has a very nice iso bypass when you’re at 12 o’clock on all a channel’s tone controls. Whatever sonic character it’s got, like its somewhat murky blending ability, our ears are apparently more sensitive to it (or at least mine used to be) compared to what TruRTA and RightMark can pick up on going digital to digital in situ, as it were.

It seems like you have a problem on your X1850, though, as your electronics are going bonkers doing something very straightforward that it’s designed to do. I know my X1700s do some funky things if you change settings on them and don’t reboot, so perhaps the newer X18xx model has such constraints. If that doesn’t fix it, you probably should look into getting it exchanged or serviced, I guess.

Just a question for clarification to follow up on this. Isn’t the player (assuming that one uses something like a SC6000 which is fixed at 96) already doing the conversion? So in my understanding, if I play a 48 file on the SC6000 it will convert this into a 96 signal and send it to the mixer. In this scenario, the 1850, when set to 96, does not convert anything as it is getting a 96 signal already (even though the file was 48 originally).

Or do I get that wrong?

2 Likes

@Marek_Reuter exactly. Somewhere noise (distortion) has to be added in. You cant just magically upscale a 48 to a 96… the info just isnt there so the upscale just makes it up. Hence distortion.

The SRC for file rate compatibility appears to be at least part of the SC Prime players’ own speed change algorithm, or rather vice versa. So, keylock off and moving the slider around and it needing to resample everything to whatever work rate it’s using appears to be all part of the same thing on them. My understanding is that if you’re just doing the speed change on digital DJ media players that are at the same rate already as the file, it’s only part of the SRC stuff, but in the case of the SC Prime players, it just does the whole shmeer.

And to be fair, the SRC on the players does do some interesting things. While it’s arguably half-@ssed, overly-efficient, and unnecessary in the first place with impulse amplitude oscillation, intermodulation distortion (a type of nasty nonlinear distortion, basically one of the worst-sounding and audible types of subtle audio distortions), and has a bunch of ultrasonic distortion (perhaps aliasing ‘reflection’), it does have a fairly clean impulse response for a computationally-efficient real time SRC, even if it seems to do nothing else right except having a clean impulse and being computationally-efficient.

Run a live, continuous impulse test, and you can see the amplitude oscillation of them. Run a frequency bandwidth test of sufficient treble extension, and you’ll see the ultrasonic garbage being added, as well as the poor extension of the original sonic content (be careful what you wish for asking for just more extension if they don’t change anything else). Run either a proper IMD test or just watch a test tone sweep on a real time frequency analyzer to see the extra harmonics being generated that aren’t even linear harmonics that move in a direct, fractional/multiplier manner with the test tone.

If you want to learn more about how SRC methods vary, you can look at the following and compare various post processing (i.e. not real time) software methods that are even hit or miss:

https://src.infinitewave.ca/

Oh, and you might be interested in this:

https://community.enginedj.com/t/sc-prime-player-sample-rate-selection-and-spdif-enable-disable-preference-setting/42139

If You Own X1850 Mixer I Would Suggest You check for the Following Fault. This Is Only an Issue when set to 96k digital output, it’s ok on 48K.

Connect all 4 analogue inputs if you can. Set all 4 inputs to line All faders in the off position Turn the fader trim to each channel 12 O’ clock or more Do not play any music.

Now If you have the fault you will see the channel LED level meters start to flash slowly at the bottom light of -40 across them all in turn.

If you turn the fader trims above 12 o’ clock to max, then the lights flash higher up to -16.

This also applies to the master output volume, the higher the volume the higher up the lights flash on the VU bars to the master output.

If all 4 inputs are set to line then all 4 flash, if 2 are on line and 2 on digital only the line ones will flash. It’s reacting as if there is low volume sound there but there is not, there should be no movement of the channel LEDs if no signal or sound.

This mixer is designed to be able to have line and digital inputs work side by side at 96K.

I have reported this to InMusic but by all accounts I am the only one to do so. Apparently most DJs set the output to 48k for connection to other devices so are not aware of this.

Unfortunately after two of these mixers from different batches and both had the same fault I had to refund and go with a different manufacturer.

Even if you do not use the 96k I would suggest you at least test it and If you do have this fault please make sure you log it with InMusic and if your mixer is still under warrantee where you purchased it.

Keith

1 Like

What devices are you connecting to the line input? What cables are you using? Do they have shielding on them? Are they running near to any power cables?

Hi Stu-C There was two SC6000 connected via the 4 cables that Denon supply, not next to the power cables.

The fault has been confirmed by Denon / InMusic that there is no doubt of.

Regards Keith

Those cables that come with players are usually bargain basement items though aren’t they, they should be replaced with superior items by anyone who is serious about sound quality. Is there an audible sound coming through the channels when you turn the trim up? Or is it just lights on the mixer?

One other question, what is the purpose of turning up the sample rate on the mixer if you’re plugging the units in through the line connection? Shouldn’t you be using the digital coax to take advantage of that sample rate?

Obviously there is some issue whereby the increased sample rate is adding some sensitivity to the sound, but it’s only apparent by doing 2 things that aren’t relative to each other? (Line input and digital sample rate) and if it’s not actually causing noise to come through the signal chain is it worth worrying about?

Just to add, it looks like you already created a thread about this 6 months ago? Any particular reason for restarting it?

Posts moved here

1 Like