Definitive Technology Descend DN15 15" Subwoofer Review

[Kevin C]

even with floor space being an issue i would still do 2 rsl 12s . I would just stack them and smile all day. But seriously i do I agree with you that sometimes floor space is at a premium and stacking two of the 12s would be very tall. But if you put them in the corner your wife could put one of those three panel screens in front of it. Nobody would know. But i agree with your point 30 inchs tall is a good hight.

 

[oniiz86]

@shadyJ I was wondering during your time of testing the DN15 did you ever experience it displaying "LIMIT" at any point during deep low passages at around MV -10dB?

I have dual DN12s (yes before anyone says anything I understand they were a poor choice, got sucked into their egregious marketing tactics "The 12 inch plays like a ported 15 inch" & hyperbolic statements from a DN12 review https://www.stereonet.com/au/reviews/definitive-technology-descend-dn12-12-subwoofer-review "Indeed, the DN12s sound larger than I expect from a 12” driver, and in the hands of the competent DN12s, you feel like you're standing next to Wick in the nightclub." but size constraints & obscene pricing is a real problem in Australia ) & have experienced for the first time with Blade Runner 2049's opening "eye" scene one of the DN12s displaying "LIMIT" during this sequence with a sub trim level of -4dB (Audyssey set it to -10dB during calibration, boosted 6dB), Dynamic EQ enabled & MV set to -10dB if set to -15dB this scene exhibited no such issues, I believe the bass boosting nature of Dynamic EQ should be attenuated as you increase the MV closer to Reference 0dB volume, I thought the DN12s would be able to handle this approx. 30Hz frequency fairly well, is Blade Runner 2049 known to be quite the torture test for subs?

 

[shadyJ]

@shadyJ I was wondering during your time of testing the DN15 did you ever experience it displaying "LIMIT" at any point during deep low passages at around MV -10dB?

I have dual DN12s (yes before anyone says anything I understand they were a poor choice, got sucked into their egregious marketing tactics "The 12 inch plays like a ported 15 inch" & hyperbolic statements from a DN12 review https://www.stereonet.com/au/reviews/definitive-technology-descend-dn12-12-subwoofer-review "Indeed, the DN12s sound larger than I expect from a 12” driver, and in the hands of the competent DN12s, you feel like you're standing next to Wick in the nightclub." but size constraints & obscene pricing is a real problem in Australia ) & have experienced for the first time with Blade Runner 2049's opening "eye" scene one of the DN12s displaying "LIMIT" during this sequence with a sub trim level of -4dB (Audyssey set it to -10dB during calibration, boosted 6dB), Dynamic EQ enabled & MV set to -10dB if set to -15dB this scene exhibited no such issues, I believe the bass boosting nature of Dynamic EQ should be attenuated as you increase the MV closer to Reference 0dB volume, I thought the DN12s would be able to handle this approx. 30Hz frequency fairly well, is Blade Runner 2049 known to be quite the torture test for subs?

I haven't seen that, but I didn't have the LCD display facing me when I was using the sub, sorry.

I wouldn't guess that the DN12 is a bad sub, probably a few dB down from the DN15.

 

[oniiz86]

Yes, the dual DN12s do okay but I completely understand they are totally insufficient for the size lounge room with vaulted ceilings, I figured the both of them would have provided decent headroom for that Blade Runner 2049 opening "eye" sequence with 1000W RMS, perhaps too much bass boosting with an extra 6dB & Dynamic EQ but like I said, I thought it would've backed off as I increased the MV from -15dB to -10dB, I think I'll have a go with Dynamic EQ disengaged & see if it avoids engaging the limiters, I couldn't hear it clipping or distorting but was concerned all the same.

 

[haboscio]

How were you driving it? Was there a crossover involved, ot were you running from a full bandwidth output?

To be honest, I dont think so. But I am not expert. It is run out of a Marantz 6015. Both Audyssey MultiEQ and REW/Umik-1 give me the same profile. With or without Audyssey Off. Reference/Flat, does no matter. Perhaps the Marantz is applying a filter?

If so, will appreciate guidance on how to setup my AVR correctly to extend the SUB response beyond 100hz.Thx

 

[haboscio]

Did you measure it in room or out in the open for an anechoic response like Shady is doing

I guarantee you that once you put that DN15 into your room that room is going to mangle that beautiful response curve Shady is showing in his measurements and it won't be extending out as far as you see it doing here in his tests

In my bedroom I have had quality subs that extend well beyond 100hz but in my room, in the best spot for placement, measuring with REW the response drops pretty sharply after 90hz no matter what.

The room is going to affect your subs measured response in a huge way which is why as I'm sure you well know room eq is so critical in the bass region

That may be the case. And I thought of that. However, I would think the same would happen to any other speaker on the room. Yet my old Polk rTI A7 do extend down to 30hz, with quite good response from 90 to 250hz (in my room). The range I would like to see covered by my two DN12,; bc I would need my Sub to cover for my Surrounds, which roll off between 120 and 150hz. No issue with my LCR, but my surrounds would benefit from a Sub that covers below their range.

 

[haboscio]

He might have left some kind of low-pass filter on when he measured that. Also, like what Danzilla said, the room acoustics will boost the lower stuff but not the upper bass stuff, and can make an in-room response look low-pass filtered too.

Thank, appreciate any guidance on how to measure correctly / dissable any low pass filters (I am driving it using Marantz 6015)

 

[shadyJ]

Thank, appreciate any guidance on how to measure correctly / dissable any low pass filters (I am driving it using Marantz 6015)

Make sure that 'Low Pass' on the sub is set to LPF. Make sure that there is no bass management engaged on the Marantz when you run those sweeps, or set the low-pass filter as high as it will go. I would bypass the Marantz altogether when taking a sweep if possible.

 

[haboscio]

Make sure that 'Low Pass' on the sub is set to LPF. Make sure that there is no bass management engaged on the Marantz when you run those sweeps, or set the low-pass filter as high as it will go. I would bypass the Marantz altogether when taking a sweep if possible.

OK, so this may be constraining sounds above 120Hz. Will try a higher setting. Thx.

PS, the DN12 LP goes from 40 to 150 and LFE. Its currently on LFE. Will play with these too

 

[oniiz86]

@haboscio I was curious if you have experienced your DN12s displaying "LIMIT" on deep low passages with MV set to -10dB with a AVR sub trim level of -4dB & Dynamic EQ enabled, I've never driven them hard but experienced one of my DN12s potentially clipping during Blade Runner 2049's opening "eye" scene, I thought that would be a fairly mild moment of sustained bass at around 30-35Hz & not be any cause for concern but it seems the DN12 wasn't liking it too much, no such issues at all with a MV of -15dB.

 

[haboscio]

No. I have not experience any "Limit" or clipping. But I never drive my AV below -15. My Sub trim is at +4, and I occasionally use Dynamic EQ, but not much lately.

 

[oniiz86]

@shadyJ In your review you noted that when the gain was at its maximum (Volume 40) it started to compress, is that any cause for concern? Is this something that you only experienced with the DN15 because of its under-powered 500W amplification? Is this typical behaviour of other sub manufacturers with similar amp power ratings?
"To see how loud the sub could get without endangering my hearing or my speakers, I turned off the amp powering the speakers and raised the volume to max. At the top end of the gain, the DN15 did start to compress the sound, but it never ran into any audible distortion otherwise. There was never the telltale fuzziness of higher-order harmonics, and it kept a tight leash on misbehavior."

 

[shadyJ]

@shadyJ In your review you noted that when the gain was at its maximum (Volume 40) it started to compress, is that any cause for concern? Is this something that you only experienced with the DN15 because of its under-powered 500W amplification? Is this typical behaviour of other sub manufacturers with similar amp power ratings?
"To see how loud the sub could get without endangering my hearing or my speakers, I turned off the amp powering the speakers and raised the volume to max. At the top end of the gain, the DN15 did start to compress the sound, but it never ran into any audible distortion otherwise. There was never the telltale fuzziness of higher-order harmonics, and it kept a tight leash on misbehavior."

Almost all subs will compress the response at high drive levels with a few exceptions. It might be perceived as a tonal change if you are pushing the sub hard for a long duration. It's not something to worry about unless you push the sub to its maximum performance frequently, but then if you are doing that, you will soon have other much more serious problems.