Dynaudio 18s vs sub 6

[Probelou]

I'm currently trialing a Sub 6 with my Heritage Specials.

My first impressions are hugely impressive. So far it's a transformative experience.

I have a couple of queries though.

Does anyone know if the analog signal it receives from a preamp goes through an A/D conversion? My assumption is yes otherwise how would the DSP work. Or does it pass thru the signal untouched to the main speakers and just A/D the signal used for the sub itself?

Another thing I've noticed is noise/hiss coming from my speakers. Before I added the sub into the chain they were silent and now I can hear a lot noise. Could it be the cables I'm using or a hardware fault? Does anyone have any experience this?

The whole A/D part worries me slightly as the signal is now at the mercy of whatever DAC is inside the sub. Could it be this that's introducing the noise?

 

[chillwig]

I'm currently trialing a Sub 6 with my Heritage Specials.

My first impressions are hugely impressive. So far it's a transformative experience.

I have a couple of queries though.

Does anyone know if the analog signal it receives from a preamp goes through an A/D conversion? My assumption is yes otherwise how would the DSP work. Or does it pass thru the signal untouched to the main speakers and just A/D the signal used for the sub itself?

Another thing I've noticed is noise/hiss coming from my speakers. Before I added the sub into the chain they were silent and now I can hear a lot noise. Could it be the cables I'm using or a hardware fault? Does anyone have any experience this?

The whole A/D part worries me slightly as the signal is now at the mercy of whatever DAC is inside the sub. Could it be this that's introducing the noise?

"Sub 6 DSP Features
The Sub 6 incorporates signal processing that can compensate for the time delay and volume level differences between the subwoofer and main speakers resulting from their relative positions with respect to the listening position. Once you have positioned your subwoofer, measure the distances as illustrated in the diagram. The measured distances should then be specified at the appropriate locations in the subwoofer configuration menu. The configuration menu is described in the following of this manual."

my understanding is that as long as you are not using the time delay features then you are not using the DSP.

 

[Probelou]

Interesting.

I have entered the speaker distances so I'm assuming the DSP is coming into play. I'll try removing them and see if there's any audible difference. It'll be interesting to see if this gets rid of the noise I'm hearing on the main speakers.

 

[chillwig]

Interesting.

I have entered the speaker distances so I'm assuming the DSP is coming into play. I'll try removing them and see if there's any audible difference. It'll be interesting to see if this gets rid of the noise I'm hearing on the main speakers.

curious about the noise myself. are you using balanced connections? maybe try adjusting the input sensitivity.

 

[Probelou]

curious about the noise myself. are you using balanced connections? maybe try adjusting the input sensitivity.

Yes, I'm using the balanced XLR connections.

The noise isn't really audible from the listening position but it becomes noticeable the closer I get. I'm nitpicking really but as my speakers are completely silent when the sub isn't in the chain it's something that stands out to me.

@chillwig Do you own a Sub 6?

 

[3125b]

Another thing I've noticed is noise/hiss coming from my speakers. Before I added the sub into the chain they were silent and now I can hear a lot noise. Could it be the cables I'm using or a hardware fault? Does anyone have any experience this?

Oh that's normal, using the sub's crossover adds quite a bit of noise. My previous system with Focal Alpha Evo and Dynaudio 9S went from "not audible" without the sub to "quite annoying" when using the crossover. All subs will degrade the signal passed to the mains to a degree, some better some worse.
You can always just use the sub on a sub- or preamp-output and drive the speakers directly from the amp/processor.

 

[chillwig]

Yes, I'm using the balanced XLR connections.

The noise isn't really audible from the listening position but it becomes noticeable the closer I get. I'm nitpicking really but as my speakers are completely silent when the sub isn't in the chain it's something that stands out to me.

@chillwig Do you own a Sub 6?

Yes im running a sub 6 with a pair of Contour 30. However I'm letting my preamp handle the crossover currently.

 

[Probelou]

You can always just use the sub on a sub- or preamp-output and drive the speakers directly from the amp/processor.

That never occurred to me.

I'll give that a try.

The whole reason I'm trialing the sub 6 is because I was having trouble integrating my current rel carbon special. My room has a 45hz mode and I've struggled to get the rel sounding really great. It can very easily overwhelm my room but it needs a certain amount of gain before it makes a contribution. I did purchase an RME ADI-2 FS to try the EQ and it has been reasonably successful. However, I've grown accustom to my Chord Hugo TT2 and I'm not sure I wanna give it up.

I've only had limited time with the sub 6 but it's a night and day improvement over the rel in terms of integration. It's really impressed me.

 

[Probelou]

Yes im running a sub 6 with a pair of Contour 30. However I'm letting my preamp handle the crossover currently.

Have you tried it with and without speaker distance measurements? Or noticed any noise coming from your speakers?

 

[3125b]

I did purchase an RME ADI-2 FS to try the EQ and it has been reasonably successful.

Not really the best way of implementing room EQ, but it can work. What you should probably do if you can and want to keep the Chord is return the RME and get a MiniDSP and a measurement mic, read up on how to use them and give it a go. That will really help fix your problem. It's not magic and you can't cheat physics, to get the best possible results you'll need to treat the room some. But as a starting point room EQ will give you the most bang for your buck.
Start a seperate thread if you need assistance with that, there are a lot of people here who can help.

 

[Probelou]

Not really the best way of implementing room EQ, but it can work. What you should probably do if you can and want to keep the Chord is return the RME and get a MiniDSP and a measurement mic, read up on how to use them and give it a go. That will really help fix your problem. It's not magic and you can't cheat physics, to get the best possible results you'll need to treat the room some. But as a starting point room EQ will give you the most bang for your buck.
Start a seperate thread if you need assistance with that, there are a lot of people here who can help.

Thanks for the advice.

I have read about MiniDSP but struggled to understand how that would integrate with my Chord DAC. I'll start another thread to get the ball rolling.

 

[chillwig]

Yes im running a sub 6 with a pair of Contour 30.

Have you tried it with and without speaker distance measurements? Or noticed any noise coming from your speakers?

No I haven't, since my sub placement is centered between the towers and there's nothing to correct. I have however let the Sub6 handle the crossover to the towers (theres a preset for the Contour 30) and have not noticed any noise. Again, I suggest playing with the input sensitivity and seeing if that lowers your noise floor perceptibly.

 

[net-david]

"Sub 6 DSP Features
The Sub 6 incorporates signal processing that can compensate for the time delay and volume level differences between the subwoofer and main speakers resulting from their relative positions with respect to the listening position. Once you have positioned your subwoofer, measure the distances as illustrated in the diagram. The measured distances should then be specified at the appropriate locations in the subwoofer configuration menu. The configuration menu is described in the following of this manual."

my understanding is that as long as you are not using the time delay features then you are not using the DSP.

Although I have not seen a schematic for the built in amp, I'm fairly certain it is always going through an A/D conversion and through the DSP. Every other amp I've ever seen with these features does. It would be much more complex to bypass the A/D and DSP only under certain settings. Here is a block diagram of a Hypex amp:

 

[chillwig]

Although I have not seen a schematic for the built in amp, I'm fairly certain it is always going through an A/D conversion and through the DSP. Every other amp I've ever seen with these features does. It would be much more complex to bypass the A/D and DSP only under certain settings. Here is a block diagram of a Hypex amp:

View attachment 277711

I have no idea, only that the Manual discusses the DSP only in connection with the distance correction, including integration with a second sub.

Also the more that I think about it, the availability of software crossover presets for specific tower models also implies that the DSP is handling the crossovers. I guess there's no reason to think that the input sensitivity isn't similarly controlled.

So I guess using my preamp for the crossover was probably the right call all along. Were I using active towers then different story.

 

[Probelou]

I've been doing some more testing today to try and remove the noise.

I tried disabling the speaker distance measurements but all I could do was set them 0cm, I don't think this actually disables them. This didn't remove the noise.

Also, I tried changing the input sensitivity but again, this didn't remove the noise.

Lastly, I tried connecting the sub from a separate preamp output to the main speakers. This does remove the noise as the main speakers are no longer being fed a signal from the sub. However, this greatly reduced the performance of the sub. The integration wasn't there and it lost the depth and punch it has when passing the signal through the sub. I tried increasing the gain but it never reached the same level of performance. I get the impression the sub was designed to be connected as per the manual, i.e. passing a signal through the sub to the main speakers and letting the DSP do it's thing.

I will admit to being incredibly impressed with the sub when it's connected with the signal passing through to the main speakers. The whole sound stage feels more coherent and integrated and just generally, bigger. As mentioned above I think there will always be a A/D and back again conversion regardless of the settings used on the sub. I suspect this is where the "magic" happens that creates the excellent integration and performance. I'm just really struggling with the noise it introduces into the signal path. After attempting some critical listening it is really obvious to me and can even be heard, albeit slightly, at the listening position.

I have sent an email to Dynaudio about the noise and also requesting an explanation of the DSP/analog conversion process. I'm curious to know what's actually going on.

I swapped my rel carbon special back into the system while using the RME ADI-2 and spent some time tweaking gain, crossover and the EQ. It's taken a while but I think I've got it pretty well dialled in now. I wouldn't say it's completely removed my 45hz room mode but it's certainly got it under control and it's even smoothed out a few other bits of the response curve.

The rel performance is great now and I would say the bass feels a little bigger than the Sub 6, possibly slightly deeper too but I wouldn't swear to that. On the flip side the sub 6 feels a smidge faster and more assertive.

I'm not sure I'm any closer to a resolution really. I don't want to get into DAC comparisons here but does the EQ on the RME out weight any of my perceived gains of the Chord? or am I happy to live with the noise introduced by the sub 6? I don't know if I can answer those questions yet.

I will also note that, based on advice here, I'm also looking at the possibility of putting a miniDSP in front of my M-Scaler. To be continued...

 

[FeddyLost]

or am I happy to live with the noise introduced by the sub 6?

I think you should find out some guy with measurement equipment and check how exactly noise is going into your mains.
Maybe you'll live just ok with disconnected cable shield on way sub -> amps.

 

[Probelou]

I've done some room measurements of my speakers in conjunction with both my Rel Carbon Special and the Dynaudio Sub 6. Interestingly the Sub 6 appears to reach a bit lower than the Rel, at least in my room. The measurements show the Rel starting to roll off at about 35hz and it's quite a steep curve where as the Sub 6 pretty much stays in the game all the way to 20hz. These measurements have no EQ or room correction.

I've done a lot more listening and audibly their bass response sounds very similar with the Rel being ever so slightly smoother. The Rel really exaggerates my 45hz room mode if I increase the gain, even by a few clicks, but it does bring up the sub 35hz response but it's still nowhere near the Sub 6. I'm a little surprised that audibly they're so similar based on the measurements I'm seeing.

Has anyone here experienced different measurements without really being able to distinguish an audible difference?

Also, I now have a miniDSP that I've been playing around with. After some quick, preliminary measurements with Dirac it pretty much smooths out all the dips and peaks. I need to spend more time with it to get it properly dialled in though. I'm wondering if it will allow me to increase the gain on the Rel to bring up the sub 35hz while smoothing out the 45hz peak.

More testing is needed.

 

[LucreciaBorgia]

Hi everybody
I am a bit surprised that nobody is discussing (using ?) the High Pass filter on the sub 6/sub 18: Isn't it the best way to use a sub, and integrate "satellites" ? and at the same time sparing your amplifier the power-hungry low frequency amplification ?
There are not so much subs having this functionality, so I would expect lot of comments/feed back on that...
If I buy this sub, it would be only for this possibility !

 

[FeddyLost]

I am a bit surprised that nobody is discussing (using ?) the High Pass filter on the sub 6/sub 18: Isn't it the best way to use a sub, and integrate "satellites" ?

It's a mediocre solution due to 2 reasons
1) for good subwoofer integration in real world user needs little more than HPF
2) sending sinal to mains through any subwoofer will never improve it and most probably degrade it
It's a quick and dirty way of integration sub with NFMs for bedroom producers.

 

[LucreciaBorgia]

It's a mediocre solution due to 2 reasons
1) for good subwoofer integration in real world user needs little more than HPF
2) sending sinal to mains through any subwoofer will never improve it and most probably degrade it
It's a quick and dirty way of integration sub with NFMs for bedroom producers.

It will not improve, but it will send to the amplifier only frequencies above 80Hz, making his life much easier, and most probably improving its performance for the upper frequencies...
Unless you have very bass competent loudspeakers (but in this case, why do you want a sub ?) why not letting each one doing the job he is best at ? My experience in integration is that there is always a frequency where both sub and LS are adding eachother, making the whole magic disapear...
...and I don't understand your point 1