Integrating subwoofers with planar speakers

[mglobe]

A friend of mine is interested in adding a sub(s) with his Magnapan 1.7i's. He's reached out to me for info/help. Conventional "wisdom" seems to be that its difficult at best to do, but I've not found very specific explanations for why, nor well founded suggestions on how to go about it. Most of what I read talks about the "speed" of planers, and the difference in radiation patterns. I'm not convinced that it can't be down well.

Interested in comments/insights.

Please don't suggest other main speakers. These are in his second system, and he loves the Maggies for the sound field they project.

 

[Keith_W]

I don't see how it would be any different to integrating a sub with any normal speaker. The principles are the same - use more than 1 sub if possible, find the best placement for the subs, then dial them in with DSP.

FWIW I think that when people talk about subwoofer "speed", they are talking about poor integration. A poorly integrated sub will sound plodding and "slow". Once it is properly integrated the experience is seamless.

 

[MAB]

A friend of mine is interested in adding a sub(s) with his Magnapan 1.7i's. He's reached out to me for info/help. Conventional "wisdom" seems to be that its difficult at best to do, but I've not found very specific explanations for why, nor well founded suggestions on how to go about it. Most of what I read talks about the "speed" of planers, and the difference in radiation patterns. I'm not convinced that it can't be down well.

Interested in comments/insights.

Please don't suggest other main speakers. These are in his second system, and he loves the Maggies for the sound field they project.

One of the many urban legends: planar speakers don't integrate well with subs.

I worked in a store that sold Magnepan, I thought this anecdote was true until I tried it. First with a pair of Vandersteen 2W subs because someone said they are fast subs. It was so successful I tried it with a big Velodyne sub, which was said to be a slow sub. It also dramatically improved the sound. I later learned the idea of a fast or a slow woofer was complete BS.

With the simple crossovers available on the subs back in the '80s, I got great results. I did have to do this all by ear, likely didn't even come close to what I would now consider a good result since a measurement mic was way out of my price range and I was only beginning to see how important measurements are.

Modern sub crossovers, be it a MiniDSP or some of the more advanced internal crossovers, are far superior to the simple filters in those old subs. Subs fix one of the biggest shortfalls with Magnepan and other planar speakers.

Of all the speakers, planar seem to benefit more than most, and are no more difficult to integrate, perhaps even easier. Which is one of the many ironies in audio, for some reason these urban myths seem to tell us to do the opposite of what actually improves sound reproduction.

 

[mglobe]

I’m honestly not surprised at the responses to my questions. It’s what my understanding of the physics of speakers suggested to me was the case but wanted to hear from others. I supposed it was possible that I was missing something.

 

[dlaloum]

20+ years ago I tried to integrate an Audio-Pro Sub with my Quad ESL63 panels....

The integration tools were crude to non-existent, and I never could get the setup sounding right...

But I had no Mic's or other helpful tools - so a lot of subjective poking in the dark.

Ultimately I gave up on trying to match subs to planars...

Doing it nowadays is a completely different thing!

 

[Jim Taylor]

Some people believe a dipole speaker mates best with a dipole bass unit, so you might find value in this. It's Sigfried Linkwitz's design of a dipole woofer, ostensibly to accompany dipole speakers. Notice the links at the top for two more designs, and do not forget the necessity for equalization, mentioned in the text.

Dipole Woofer

John Kreskovsky's Music and Design website is gone as of 2019, but David Ralph has his permission to host the archival pages, along with many other subjects.

David Ralph's Speaker Pages - Home of the Windows Passive Crossover Designer (WinPCD)

www.speakerdesign.net

Kreskovsky was considered a major source of information of dipole design, including bass units.

U-frame DIY

Have fun!

 

[klettermann]

I'm running MGIIIa's (factory rebuilt) with 2 subs and it's superb. I spent a long time messing with REW, MiniDSP, etc. No "integration" issues, just working through the trqnsition and getting timing right.

 

[dlaloum]

A further comment on sub / panel integration...

I have listened for substantial periods of time to various of the Martin Logan "Hybrid" panels, with the built in subwoofer.

Although I tried valiantly to like them - I never found the bass to be "of a piece" with the other frequencies.... there was a definite disconnect in the timbre/texture of the bass vs the midrange... which always bothered me.

Although we have a lot more tools for SW integration - the fact that a vaunted speaker designer like ML could not integrate properly within the speaker, has always made me think that there is definitely something to the belief that panels integrating with subs is a difficult conundrum....

Years ago, Gradient made a "panel" sub, to mate to the Quad ESL63 panel speakers (the SW-63) - they were reviewed a number of times, and consistent reports of good integration resulted... They are very rare here in Australia, and I have never had a chance to audition a set - so I can make no personal experience based comments.

 

[Willem]

I have a pair of Quad 2805 speakers, and have used them with first one and ultimately three subwoofers. In my first attempt they did not integrate well. The subwoofer sounded woolly and booming to such an extent that I lowered the crossover frequency and the subwoofer's level to such an extent that having a sub at all no longer made much sense. But at least the booming bass was gone. I then discovered the importance of room modes, and installed a DSpeaker Antimode 8033 dsp room eq box to tame the sub. The improvement was remarkable. My conclusion was and is that since dipoles excite fewer room modes they sound so much cleaner than any non equalized subwoofer, and the transition from clean to muddy is obvious. So the solution is to use dsp room eq - if you do, subs will integrate nicely with dipoles. The current system crosses over at 80 Hz, and the three subs are equalized by MSO/miniDSP2x4HD.

 

[DanielT]

Slightly OT:
Isn't the biggest challenge, or the most fun thing about dipoles, to test placing them at different distances from the back wall? The further away from the back wall the more non-dipole they should sound. The closer to the back wall with the reflexes it creates, the result should be a fuller, larger soundstage, ("airier" as I've sometimes heard dipoles described) but then, in that case / the placement, at the expense of pinpoint accuracy in the sound? Is my hypothesis correct, those of you who have had, have dipoles and tested this?

Regarding integration with subwoofers, I have nothing more to add than what has already been mentioned in the thread. Good luck with the testing, placement, measuring sub EQ and so on.

One of the many urban legends: planar speakers don't integrate well with subs.

I worked in a store that sold Magnepan, I thought this anecdote was true until I tried it. First with a pair of Vandersteen 2W subs because someone said they are fast subs. It was so successful I tried it with a big Velodyne sub, which was said to be a slow sub. It also dramatically improved the sound. I later learned the idea of a fast or a slow woofer was complete BS.

With the simple crossovers available on the subs back in the '80s, I got great results. I did have to do this all by ear, likely didn't even come close to what I would now consider a good result since a measurement mic was way out of my price range and I was only beginning to see how important measurements are.

Modern sub crossovers, be it a MiniDSP or some of the more advanced internal crossovers, are far superior to the simple filters in those old subs. Subs fix one of the biggest shortfalls with Magnepan and other planar speakers.

Of all the speakers, planar seem to benefit more than most, and are no more difficult to integrate, perhaps even easier. Which is one of the many ironies in audio, for some reason these urban myths seem to tell us to do the opposite of what actually improves sound reproduction.

Regarding the myth of sluggish, slow subwoofers and fast eletrostats and the impossibility of integrating them well that follows from that.

What are fast eletrostats?

IF eletrostats were "fast" then, if you take it from a purely mechanical perspective, they should not be able to reproduce midrange frequencies. They are by definition slower than what they are in the higher frequency registers. Which of course is complete nonsense because any full-range eletrostat can handle it. So what is this fast? No lingering resonances that ringing perhaps? If it can be generalized?

One thing that eletrostats have is an advantage in is that they can have incredibly low distortion. I can imagine vintage eletrostats vs vintage box speakers with dynamic high-distortion drivers that it plays a role. This distortion should be, or maybe is audible? The inaudible distortion in electrostats may be the origin of this view that electrostats are "fast" and have high clarity in the higher registers? Which, by the way, can be seen as a definition, low distortion = clarity

Just a few thoughts on my part.

 

[dlaloum]

Slightly OT:
Isn't the biggest challenge, or the most fun thing about dipoles, to test placing them at different distances from the back wall? The further away from the back wall the more non-dipole they should sound. The closer to the back wall with the reflexes it creates, the result should be a fuller, larger soundstage, ("airier" as I've sometimes heard dipoles described) but then, in that case / the placement, at the expense of pinpoint accuracy in the sound? Is my hypothesis correct, those of you who have had, have dipoles and tested this?

Regarding integration with subwoofers, I have nothing more to add than what has already been mentioned in the thread. Good luck with the testing, placement, measuring sub EQ and so on.

Regarding the myth of sluggish, slow subwoofers and fast eletrostats and the impossibility of integrating them well that follows from that.

What are fast eletrostats?

IF eletrostats were "fast" then, if you take it from a purely mechanical perspective, they should not be able to reproduce midrange frequencies. They are by definition slower than what they are in the higher frequency registers. Which of course is complete nonsense because any full-range eletrostat can handle it. So what is this fast? No lingering resonances that ringing perhaps? If it can be generalized?

One thing that eletrostats have is an advantage in is that they can have incredibly low distortion. I can imagine vintage eletrostats vs vintage box speakers with dynamic high-distortion drivers that it plays a role. This distortion should be, or maybe is audible? The inaudible distortion in electrostats may be the origin of this view that electrostats are "fast" and have high clarity in the higher registers? Which, by the way, can be seen as a definition, low distortion = clarity

Just a few thoughts on my part.

They also don't have boxes to resonate....

They can have their own resonances, but in my experience, the "box" is frequently obvious if you are used to panels...

 

[boxerfan88]

FWIW I think that when people talk about subwoofer "speed", they are talking about poor integration. A poorly integrated sub will sound plodding and "slow". Once it is properly integrated the experience is seamless.

10000% agree.

 

[boxerfan88]

On my system, I had to delay my mains by about 5.9ms because my KH310 was "faster" than my lazy sub. A lot of measurement-experiment-repeat to get the timing right.

I'd also suggest the mains & subwoofer be properly crossed over. I find running both in parallel doesn't really sound that good. (For me at least).

My simple test is to have the subwoofer in standby. Play a track with sufficient bass. The mains will play first, then it's like the mains suddenly grew a big pair of woofers. They play as "one".

If not dialed in properly, the bass notes on some tracks may sound a bit "off". (To me sometimes it sounds like "whoop whoop bass".)
If dialed in properly, the entire system plays whatever track you throw at it, as "one". (I would describe it as "tight" ... a solid thump or bass note then quickly decay.)

 

[A Cute Earring]

I ran my Magnepan 1.7i’s with a pair of SVS SB 1000 pro’s and was VERY happy with the results. Placement is key.

 

[Sokel]

Wherever I experienced "speed" down low, was with large cones without particularly great x-max and freq response no lower than 30Hz.
Room treatment (yes, big bass traps) help enormously too. No DSP is a cure to this.

 

[DanielT]

They also don't have boxes to resonate....

They can have their own resonances, but in my experience, the "box" is frequently obvious if you are used to panels...

I missed that aspect. So can the case be with poorly constructed box speakers vs. planar/non-box speakers.

There can also be the case with well constructed non-resonant box speakers vs. resonant ditto.

 

[dlaloum]

I missed that aspect. So can the case be with poorly constructed box speakers vs. planar/non-box speakers.

There can also be the case with well constructed non-resonant box speakers vs. resonant ditto.

The other aspect, is that so many audiophiles have grown up with box resonances, that they automatically "tune" them out - they simply don't notice that specific type of distortion...

Many years ago, I shared a home with a young woman, who became used to my Quad panels - which she always claimed she cared nought about... sound no different to anything else etc....

Then I had to send them away for a service and temporarily replaced them with a pair of very well regarded "box" speakers... she walked in when there was music playing, did not notice that the speakers had changed (which says something... as they could not look more different!) - then turns to me and asks : are you playing this in mono? it doesn't sound right.... yes, the magic of the Quad midrange was missing.... and indeed it did not sound as good.

But it just goes to show, without the months of acclimatisation to the panels... the other speakers would have sounded "fine".

 

[mglobe]

Aren’t subwoofers slow by definition? They don’t reproduce frequencies above whatever the cutoff is (80-120hz typically). Isn’t any transducer playing 80hz oscillating at the same speed? I mean a small cone, high excursion woofer would have a higher linear velocity as a large cone low excursion one playing at the same SPL, but I highly doubt that we can hear any difference in velocity.

If we’re talking slow in terms of delay caused by built-in circuitry in the sub, that clearly would need to be adjusted for either with phase or location.

Am I missing something?

 

[DVDdoug]

Aren’t subwoofers slow by definition?

Yes. It's some kind of perception... Probably frequency response. Or maybe it's resonance and ringing in the room.

Another one is "tight bass" and here's a quote from Floyd Toole's book:

The NS-10M was admired because of its "tight" bass, a consequence of the deficiency of bass fundamental frequencies.

 

[DanielT]

The other aspect, is that so many audiophiles have grown up with box resonances, that they automatically "tune" them out - they simply don't notice that specific type of distortion...

Many years ago, I shared a home with a young woman, who became used to my Quad panels - which she always claimed she cared nought about... sound no different to anything else etc....

Then I had to send them away for a service and temporarily replaced them with a pair of very well regarded "box" speakers... she walked in when there was music playing, did not notice that the speakers had changed (which says something... as they could not look more different!) - then turns to me and asks : are you playing this in mono? it doesn't sound right.... yes, the magic of the Quad midrange was missing.... and indeed it did not sound as good.

But it just goes to show, without the months of acclimatisation to the panels... the other speakers would have sounded "fine".

Don't take offense now. I'm using myself as an example to show what I mean. One of the worst things I know is being able to pinpoint the sound to the speakers.
I want them to "disappear" so to speak.

In any case. I find that my pinpointing ability varies from day to day. Whether it's due to concentration difficulties, musical material OR an imaginary notion that I can pinpoint and that's why I do it, I don't know. It could also be a combination of all of the above.

With that said. Do you think you hear box sound, box resonances because you expect it to be there? Or are there really, objectively, resonances that are audible that you experience? In any case, as I said, don't take offense. It was just a thought.