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Hi everyone.
It's been a while and hope everyone has been v well and safe.
Wanted to ask a question. A friend on a UK forum is interested in buying some new smallish Maggies., - probably the 0.7i, but he saw a video on YouTube that suggested you'll have limited volume when driving then full range, and it's better to high pass the Maggies and use subs.
The video is here.
https://m.youtube.com/watch?v=uXErcOEdTuI&t=340s
What the guy in the video is describing with the panel buttons etc and the sound distortion issue sounds like IMD. I also assume that although Magnepan might have addressed this to some extent in the design, it's might be more of an issue with the current Maggies range that use all 1st order crossovers (compared to the older range that use steeper slopes) due to the greater overlap of frequencies.
The amps in the video he is using are 170 watts a channel. Might it be possible that some of that distortion is also caused by amp clipping? as in the past I had clipping sometimes on 3 series models when driving v loud with an amp of that kind of power.
Or might it be a combination of both clipping and IMD?
The chap in the video then switches to using the subs and a steep high pass filter on the Maggies with no distortion at higher volumes, I might be wrong but I think the speaker amps won't then have to dish out as many watts for a given volume, as the bass is rolled off (I might be wrong though so please correct me if so).
I guess it might be impossible to say for sure what the distortion is caused by unless measurements etc are made but was just wondering what you guys think of this?
I explained to the prospective buyer that the subs in that video are h frame open baffle and probably very pricey (particularly with the servo amp driving them), and quite different to the REL box subs he owns now and intends to use with a smaller Maggie. I explained that there will likely be some bass blending issues due to the different bass radiation patterns not being compatible.
I explained that it's also likely the vol levels in this video are likely pretty high, and probably higher than he would listen to most of the time.
I also explained to get good bass extension with a Maggie it better to buy a bigger model in the first place, but I'd be interested to hear views on using them with subs.
A few years ago I ran some 3.3Rswith a REL strata (closed box traditional sub) but ran the speaker full range and set the REL to the lower filter setting and placed it near the wall. I got better results like that than high passing the Maggies sharp at 80Hz, although the Maggies were still being run full range so there was still excursion issues etc when the vol was turned up v loud.
If this issues above is likely to be IMD when driving the speakers full range, is it also an issue with bigger current Maggies too? Say for the all first order 3.7i, compared to a previous 3 series model - for example the 3.5R, that used 3rd/2nd/3rd/2nd order stock XO slopes?
Any info/advice would be much appreciated.
Follow Ups:
IMO the current 3.7 or 3.7i do not go much below 40 Hz. and do need a sub.The older 3 series go to 30 Hz in most rooms and I do not use them with subs.
At low frequencies the 6 footers radiate a sound stage that is 6 feet tall and when used with a short sub the transition in sound stage height at low frequencies shifts to a shorter soundstage.
I hate that soundstage effect and do not recommend subs with the older 6 foot Magnepans.
YMMV
Edits: 12/30/20 12/30/20
I agree with you on the subs with the 6 foot 3 way ribbon Maggies. I had two pairs of 3 series a few years ago (MGiiia and 3.3R) and found what you describe. I eventually ditched the subs and just used both speakers full range as I far preferred the bass of the Maggie bass panel. The bass extension was generally enough, apart from some on material. A 20 series would obviously be better.
I didn't personally find rolling off the speakers with a XO higher up and using a sub underneath as nice as running the speakers full range and using that fast and big area bass panel. I missed that bass quality. The ported subs I tried were the worst and sealed subs better.
The problem is a ported sub can start but not stop fast enough compared to the way Maggie bass panel can. I also tried an open baffle sub with one driver but that was also a bit slow and didn't add anything. The bass area wasn't wide enough too Those GR research diy subs with 4 drivers look nice though, and the servo amp should enable them to stop much quicker. The bigger area with 4 drivers and more similar bass radiation than a closed box sub pattern might make them much more acceptable. I'd like to try those.
The bass result I had using a sub was running the speakers full range and using an REL strata 3 on its very lowest filter setting in tandem, although the speakers don't have any excursion protection like that so there is no increased max volume. In the end I still preferred the speakers without a sub as the bass was better integrated still.
Never tried a bipolar sealed sub like Satie suggested to me a few times before but would like to.
Yes I've heard that the 3.7 and i don't have an much bass extension as the older 3 series. That's a shame. The midrange panel is bigger and the bass panel smaller compared to older 3 series which is probably the main cause. The 3.6R also has same size panels as the 3.7 and I've heard similar things about that too, although possibly it is not quite as bad. Heard varying things on the 3.6 bass extension.
The 3.7 has first order XOs which I usually personally like more than higher order XOs, but it will cause more limited volume compared to older models, which also isn't too great, along with the reduced bass extension issue...
I have active 3-way Maggies - which are basically IIIas with the mid on a separate sheet of mylar to the bass panels. Or you could call them T-IVas with only 1 bass panel.
I pass over to sealed subs with a 24dB L-R XO @ 80Hz; my miniDSP unit enables me to swap between 4 different stored configs 'on the fly' - so I can easily compare running my Maggie bass panels full range vs. chopping them off and bringing in the subs.
I much prefer the latter.
Andy
Hi Andy,
Did you tune the tension button on the 2.6R bass/mid panel to a lower frequency when you reframed them?
I had some 2.6Rs, MGIIIas and 3.3Rs at the same time in the past and directly compared them all. The 2.6R was far lighter and less extended in the bass than the 3 series models. Probably due to the combo of it being a 2 way rather than a 3 way, a less area. I found the 3 series models vastly better and sold on the 2.6Rs very quickly. The panel area on the 3 series is about 800 sq in (with the midrange part) compared to 609 for the 2.6R panel.
So when run full range it might not be such a fair comparison to a 3 series model as you are using the 2.6R panel on the bass, compared to the 3 series bass panel, which is tuned lower and is also larger, although I appreciate the XO setup you have on the speakers is three way, not two way, so that must make some difference.
Yours mids and bass are on separate sheets of Mylar, which helps with congestion etc compared to a stock 3 series.
Assume that your subs are sealed?. Where do you place them in the room? Are their amps standard or servo type?
No I didn't (as I didn't know how to do this!).
Now, you said: The panel area on the 3 series is about 800 sq in (with the midrange part) compared to 609 for the 2.6R panel .
Leaving out the mid panel area on the IIIa - you get bass panel areas of:
* 620 sq in for the IIIa, and
* 609 sq in for the 2.6R.
So not so very different, I suggest. :-))
I never listened to 2.6Rs - I had had IIIas for about 15 years and when I reached the end of my upgrade path, I decided to try and create a IIIa which had a separate mid panel (to get rid of IMD - and vibrations from the bass panel getting to the ribbon cage).
After a couple of years looking, I was able to find the bass panels from a pair of 2.6Rs (which were shipped from Rome) ... and the mid/tweeter panels from a pair of T-IVas (which were shipped from Detroit).
The cross over uses stock IIIa slopes - although I tweaked the filter roll-off points slightly, to get a smoother overall FR. I use a 3-way active XO, using a miniDSP.
Yes, my subs are sealed (outside dimensions are about 3' high x 18" wide x 2' deep) with a 800w Hypex plate amp. So no servo-control.
Subs are in the front corners of the room - see here:
Andy
Thanks for the pic. Yes I remember your photos of the Frabkepans from several years ago too. Really lovely job you did on those frame etc. Wish I had those kind of DIY and woodwork skills!
I see what you mean about the size of the 2.6R and 3 series bass panels but the whole panel size on the 3 series is 800 sq m, - I know a part of it is for mids but I wonder if that greater size also has influence on bass extension. I'm also pretty sure the 2.6R panel is tuned at a higher freq than the 3 series bass section and therefore doesn't have as much extension. Although my comparisons aren't exactly the same as what you are using (as your 2.6R panel is only covering bass in a 3 way system and the stock 2.6R is 2 way) but I can say for sure the difference between the 2.6Rs I had and the two 3 series models was absolutely huge. The 3 series models sounded so much better to me. So much more range, scale, bass volume and especially bass extension. I was pretty disappointed with the 2.6R, after hearing a bit of hype about it.
I once restored a full set of Tympanis IVas in 2012. I had the full set with all the original bass panels with Mylar in tact (the seller delivered them to me. IIRC you had some that got damaged and that was very back luck, (was that you?)). My set came with the mid and bass panels delaminated and having lost continuity. The tweeters worked fine and were original 3 ohm thin wide types. It took me two months to rewire the mid and bass panels, but the speakers didn't work so well in the room I was using at the time compared to the 3 series models. The room was 15 by 24 and wasn't big enough. I was only able to set up the speakers widthways over the 15 ft wall due to various reasons, and it didn't work so well. The bass was very overwhelming and muddy. So I sold them and went back to just using the 3 series models. In hindsight I wish I had tried the IVa mid and tweeter section with a 3 series bass panel only,
which I could have easily done. It might have integrated well and worked much better in that room than the IVa bass panels. Much less width and not so spread out. Separate Mylar for mids and bass, like your setup.
I also didn't know about a trick Satie used on his Tympani IV bass panels on another room of less than ideal size which was to cross over the bass panels lower than stock (stock is 350 Hz Maggie 3rd order LP IIRC) - he changed to a 200 Hz LR 4th order low pass which kept the lower mids out of the bass panels and from spreading out too far. Mind you he used the Neo 8 mids which could play lower than the Maggie mids so he could cross over lower.
I like the sound of the slightly modified MGIIIa XO slopes you use. Less peaky than stock in the mids than the MGIIia XO would generally be a v good thing for most people. (Although some people like those hard mids). Using the passive speaker level XOs I preferred
the MGIIIa with first order mids rather than 2nd order (like the MGIII XO). That was also a bit less peaky. Did you try that too?
Those subs you have look very nice. Bet the system sounds great with those. I was told before by someone (can't remember who) that with Maggies when using a sealed box sub it's important to place subs in the corners
of the room, as if you don't, some of the bass travels to the back wall first and then to the listener (which is a longer overall distance) and it can sound slower than having them in the corners.
Thanks for the pic. Yes I remember your photos of the Frabkepans from several years ago too. Really lovely job you did on those frame etc. Wish I had those kind of DIY and woodwork skills!
I see what you mean about the size of the 2.6R and 3 series bass panels but the whole panel size on the 3 series is 800 sq m, - I know a part of it is for mids but I wonder if that greater size also has influence on bass extension. I'm also pretty sure the 2.6R panel is tuned at a higher freq than the 3 series bass section and therefore doesn't have as much extension. Although my comparisons aren't exactly the same as what you are using (as your 2.6R panel is only covering bass in a 3 way system and the stock 2.6R is 2 way) but I can say for sure the difference between the 2.6Rs I had and the two 3 series models was absolutely huge. The 3 series models sounded so much better to me. So much more range, scale, bass volume and especially bass extension. I was pretty disappointed with the 2.6R, after hearing a bit of hype about it.
I once restored a full set of Tympanis IVas in 2012. I had the full set with all the original bass panels with Mylar in tact (the seller delivered them to me. IIRC you had some that got damaged and that was very back luck, (was that you?)). My set came with the mid and bass panels delaminated and having lost continuity. The tweeters worked fine and were original 3 ohm thin wide types. It took me two months to rewire the mid and bass panels, but the speakers didn't work so well in the room I was using at the time compared to the 3 series models. The room was 15 by 24 and wasn't big enough. I was only able to set up the speakers widthways over the 15 ft wall due to various reasons, and it didn't work so well. The bass was very overwhelming and muddy. So I sold them and went back to just using the 3 series models. In hindsight I wish I had tried the IVa mid and tweeter section with a 3 series bass panel only,
which I could have easily done. It might have integrated well and worked much better in that room than the IVa bass panels. Much less width and not so spread out. Separate Mylar for mids and bass, like your setup.
I also didn't know about a trick Satie used on his Tympani IV bass panels on another room of less than ideal size which was to cross over the bass panels lower than stock (stock is 350 Hz Maggie 3rd order LP IIRC) - he changed to a 200 Hz LR 4th order low pass which kept the lower mids out of the bass panels and from spreading out too far. Mind you he used the Neo 8 mids which could play lower than the Maggie mids so he could cross over lower.
I like the sound of the slightly modified MGIIIa XO slopes you use. Less peaky than stock in the mids than the MGIIia XO would generally be a v good thing for most people. (Although some people like those hard mids). Using the passive speaker level XOs I preferred
the MGIIIa with first order mids rather than 2nd order (like the MGIII XO). That was also a bit less peaky. Did you try that too?
Those subs you have look very nice. Bet the system sounds great with those. I was told before by someone (can't remember who) that with Maggies when using a sealed box sub it's important to place subs in the corners
of the room, as if you don't, some of the bass travels to the back wall first and then to the listener (which is a longer overall distance) and it can sound slower than having them in the corners.
That's very interesting, Colin. Maybe that's why so many people have reported that adding subs spoilt their Maggie sound?
I certainly don't hear any mismatch between the subs and the bass panels You can't really see the sub cones move (when the covers are taken off) - all that seems to happen, when the subs are running, is that the sound stage widens and the Maggies seem to have grown some cojones! :-))
Andy
The way the Finish designer described placing the subs in the corners and the reflection issue when not doing so made a lot of sense. I had always previously thought it was better to place the subs closer to the listener, away from the corners or wall and in line with the speakers, but I hadn't considered how part of the bass wave would travel to the front wall and back.
Sounds like corner placement works really well in your system. So do you just use a symmetrical 80 Hz 4th order XO? Someone else (I think it was Satie) suggested to me to use a 4th order 80 Hz HP on the Maggies and try varying the sub 4th order LP, maybe trying it a bit lower, say 50 or 60Hz, - to try to stop the dipole bass and sub bass radiation patterns interfering too much.
... leave the Maggie HP @ 80Hz but make the sub LP lower.
I will try that soon. :-))
Andy
Good luck! Will be interested to hear how you get on :-)
I have played around a lot with different setups between 1.6 and subs last 5 years... I share same experience - sealed is a good general route to go and at least 2 subs, one per side behind mains near corners. Room modes will help bottom end of subs, but you need to run PEQ to tame and make them sing correctly so it not becomes a boomy/one note bass sound... Phase is also a key to make them integrate. It is important to have some knowledge to make a sub integrate well. Actual room and setup are what it comes down to.However, I have experienced that Maggies do clean/tight bass quite well in untreated rooms due to its dipole design. If you add a dynamic sub you will hear a lot more of that boomy, one note, sound. Dipole seems to be more forgiving generally with room acoustics.
I have tried both extra Maggie bass panels and 3-4 different ordinary dynamic subs. Bass reflex was not able to match due to lack of speed (I guess) and adding Maggie bass panel was not pleasing enough in the punch area so I ended up with multiple subs in closed cabinets. I believe dynamic drivers in dipole config can be even better and Rythmiks with servo systems the end of the road???
However, if you know what you are doing and relief Maggies around 80hz with 12-24 dB HP and work with phase/distance and have a parametrical EQ at hand you will end up with a great sounding system. This will bring clarity to the panels when going little louder. The only down side to Maggie design is bass slam and attack (IMHO) and some music needs well integrated subs to please me, some music not. You pick speakers upon music taste. But I can be wrong about attack as it can be my large room that is playing tricks on me. But I seldom here people talk about Magnepan speakers when it comes to moving air. Rock and EDM sounds thin and bright on lonely Magnepans, but heavenly on less processed genres.
I run my setup through a HT receiver to get it right with filters and distance through mic setup, EQ and a Velodyne SMS-1, but thats me.
Edits: 03/11/21 03/11/21 03/11/21 03/11/21 03/12/21
ColinB wrote: "I once restored a full set of Tympanis IVas in 2012. I had the full set with all the original bass panels with Mylar in tact (the seller delivered them to me. IIRC you had some that got damaged and that was very back luck, (was that you?))."
That was probably me. I repaired the midrange drivers, used foil conductors. Looked great but unfortunately the Mylar came lose on the double sided tape that splits the diaphragm into smaller sections. Basses were re-wired by the guy I bought them from. Ripped a ribbon, the original one from 1985. Have a spare set of the narrow ribbons.
I remember now who advised me to put subs in the corners of the room. It was the designer of DSPeaker antimode products in Finland. Can't remember his name.
When placed in the corners, I would think it would be a lot better to use two subs rather than one as the bass would be more even around the room.
I think that the cones on sealed subs usually don't move like they can do on ported subs as the sealed box has a natural 2nd order HP due to and determine but the size of the sealed box. With a ported sub it's a good idea to add a subsonic filter to stop those crazy subsonic movements below port resonance. On the antimode device there is a 10 Hz subsonic filter for this that works well (although I still don't recommend using a ported sub for Maggie as they are too slow - leave them for Home Theatre use).
FWIW, read the technology page on Brian Ding's Rythmik Audio page about what problem his servo is trying to address and then consider how it applies to an OB/Dipole sub.https://www.rythmikaudio.com/re-radiation.html
"...
Bass re-radiation animationThe animation above shows how definition is lost in conventional subwoofers, ...
What causes the problem?
One cause of this problem is what happens inside the box . A subwoofer driver produces output on both sides of the cone. An ideal subwoofer is one in which the output from the rear of the driver is either eliminated completely inside the box ... Sealed subwoofers seek to eliminate the rear wave. The problem in the case of sealed subwoofers is that the rear wave is re-radiated through the cone.
..."
Edits: 12/31/20
Design execution is what matters most in a sealed subwoofer, and that comes down to sufficient internal damping. The box resonance and cone re-radiation of a well damped, sealed subwoofer system should be negligible. In a properly designed sealed sub, rear wave radiation back through the woofer cone should be virtually nil.
Cheers,
AuPh
I think you missed the point.
Nope, I haven't had that much alcohol yet, even though it is New Year's Eve. 🍺
Cheers,
AuPh
Good DSP & algorithms. They work fantastically now. Try Anthem ARC or Dirac.I use Anthem ARC with my 3.6 and a sub. Before I was running the mains full range and supplementing the sub heavily low passed, crossing below 40 Hz (as the main panel has a big resonance at about 42 Hz). Now, with ARC the crossover is at 70 Hz, and with the rest of the measurement, correction & processing, it sounds amazing. You get the 'snap' and energy of many box speakers with the full clarity and immersion of maggies that they don't have. It fixes the primary issue with the 3.6 (a low/mid bass opacity compared to the best) with no downsides---if you limit the upper range of correction to somewhere between 500 to 1500 Hz as the manual recommends. It's still just a single sub and I didn't even work very hard to optimize its placement---the system correction can do wonders.
I use a lower end Anthem 310 MRX receiver (and preouts to external power amp for the mains) and it works great, plus of course multichannel & video for movies & netflix. And Dolby Volume.
Edits: 12/30/20
I high pass Acoustat 1+1s in the HT system because first octave bass excursion limits their output.
They are happier with dual subs carrying that burden.
If that were a 20.x model, however...
Some people get it right occasionally. Congratulations.
Dave.
The benefit of high-passing the speakers has been known for decades. This is hardly a secret revealed.
The guy in the video doesn't seem to know much about the speakers actually.
Around seven minutes in he completely mischaracterizes what the buttons are for. :)
It was impossible to take him seriously after that.
Dave.
The guy in the video is a hack that sells a lot of useless expensive kits to unsuspecting naive Magnepan owners.It looks like his website is down, but if you read some of his verbiage, you get the idea.
"...
3) Place mini AudioFoil (did he misspell Audiofool ???) speaker cables between xover and panel
4) Poop your shorts at the gains you receive.
5) Clean yourself up and go back for listening.
..."https://www.verastarr.com/magnepan-fuse-bypass
The subs in his videos are Danny Richie's DIY Servo Sub kits from GR Research.
https://www.gr-research.com/diy-subwooofer-kits.html
Edits: 12/28/20
He seems like a complete clown to me. Oh well.
Thx.
Dave.
Thanks Dave,
Ah yes. I remember now that the buttons are for tensioning the panel to a certain freq, not for what he says.
Is there a chance the speaker amp is clipping a bit at the start when the speakers are run full range? Or is this just all likely down excursion issues/IMD when run full range?
How about the max vol capability of the current Maggies range with 1st order XOs compared to the older range with higher order XOs.? (When run full range)
Cheers
Colin
There's a certain amount of IM distortion "built in" to the speaker because of the mechanical crossover between the drivers. You can see this by exciting the woofer transducer and monitoring voltage on the tweeter transducer. (Or vice-versa....although not nearly as easy to see.)The "first-order" series crossovers obviously broaden the drive levels to each transducer and "blend" the drivers even further. And the single-ended operation causes more even-order distortion components. These are speakers not without significant distortion. :)
The electro-mechanical nature of these transducers has an inherent 2nd-order roll-off below resonance. Including dipole cancellation you net an approximate 3rd-order roll-off. Thus, I think it's appropriate to add a first-order electrical filter to the power amp drive that matches up (the best you can) with that 3rd-order roll-off point.
You then have a 4th-order acoustic roll-off which can be matched up to a subwoofer low-pass pretty well.That's my preferred way to operate the smaller Maggies.
Higher-order crossovers are popular too but, to me, it's difficult to blend them correctly.That said, and all other things being equal, rolling off the bass frequencies to the main panel will reduce all forms of distortion from the speaker....driven at the same nominal SPL level. That's just basic physical limitations at work.
Dave.
Edits: 12/28/20
But surely, Dave, if you do it this way ... you're not actually cutting off much low end from the Maggie bass panels? So you're still getting into single-magnet distortion territory.
Whereas if you cut them off higher - say 60 or 80Hz (with a 24dB L-R filter) - you avoid getting into excessive distortion territory ... plus reduce the load on the amp.
Andy
Yeah I had thought about this possibility too. I would probably try both methods and see if the first order method at bass roll off makes enough difference regarding distortion and max vol capability/congestion etc. I would imagine it would not be as good as a higher order electrical XO at higher freq but it might help somewhat compared to running the speakers full range, anc could make enough of a difference.
Better potential integration with a sub sound like a good positive of the first order method, and I suspect the bass extension and output of the speakers might not be too much different to running the speakers full range, which gives you the option of not using a sub too (if you want too) which isn't possible with the other method.
Perhaps this depends on which active path you go down?
Certainly with an analogue active filter, it would be difficult ... but my miniDSP unit (initially a 10x10HD) and now a nanoDIGI) enables me to store 4 configs and select one of them 'on the fly'.
So one config is "bass panels full range and subs off" - which is easy to compare against "bass panel / sub XO at 80Hz, 24dB L-R".
Andy
Yeah good point. The newer Minidsps are v flexible for sure. Those presets sound v handy. You could also try the first order HP either subs method mentioned above and compare to quickly to the others.
I'd probably still prefer to go down the HP PLLXO route with analogue active LP XOs though, but it's more work and no easy way to switch quickly to compare.
You are always in "single-magnet distortion territory" with these speakers. (Unless you have 20-somethings.)
There are advantages in higher-order/higher-slope schemes. (I don't believe I said otherwise.)
Yes, distortion would be further reduced, but you don't have the best integration (in my opinion) between main speakers and sub-woofers using that approach.
As you know, there are trade-offs at every turn with speaker systems. :)
Dave.
not using your suggestion of a 6dB HP filter which coincided with the intrinsic low end roll-off of the bass panel ... but, rather, moving the roll-off higher.
The fact that you do this forces you to use a higher-order HP filter, as you need to compensate for no longer having the "intrinsic low end roll-off".
Andy
That's interesting. Why would the integration potentially be better with the first order HP at speaker bass roll off freq method? because the XO is at a lower frequency and the ear is less sensitive to phase issues etc there?, or for another reason?
Thanks for the info. Much appreciated. That's a handy tip to get effectively a 4th order acoustic roll off. I assume a pllxo (single cap) to get that first order HP before the power amp is ok to use? Might this method produces better blending with a standard kind of sealed box sub or would you really still need dipole subs and eq etc?
I have had good luck with a minidsp to perform biamping and subwoofer blending.
Looks good, but how did you get the HSU subs to blend well? Those subs are ported and would surely be quite a lot slower than the Maggie panels. I only found sealed box subs to work ok (but still with some issues...). I prefer the bass from the Maggies panels as it's faster etc and better integrated. I really want a 20.x or the 30.7 and run them full range, but this looks like a good solution for a smaller model like the 1.6.
having four subs evens out the bass response in the room. The nanodigi crossover I have set is 24/db which also helps to keep the bass out of the magnepan response region of the 1.6's. Kinda of like my own version of the swarm system.
http://www.audiokinesis.com/the-swarm-subwoofer-system-1.html
Yes using many subs definitely evens out the bass response and is nice. What I meant was a ported sub won't stop and start like a sealed one can and is even further behind a Maggie panel in that regard. Would be interested to hear this setup. Appreciate that keeping the Maggie freq range separated from the sub range would help integration though. If it was me I'd probably only be using sealed subs though, based on my previous tests with different sub types.
Satie (is he still around?) used to recommend using bipolar sealed subs if using box subs. He reckoned they integrated better with Maggies than one driver box subs. Vanderstein used to make a few bipolar subs.
The 2 HSU TN1220's in my setup are tuned at a very low frequency, something like 18hz. So an octave or so above that they behave similar to a sealed subwoofer.
The 2 SVS SB-1000's are sealed.
The sound especially in the base region is very natural and seamless sounding in my setup.
I have a significant amount of bass trapping in the room.
Sounds interesting. Using ported and sealed subs together, and getting both of the types of bass radiation patterns.
In the past I could never get ported subs (on their own) to integrate well with some Maggie 3 series . I used some big ones too that were tuned very low. They were just too slow. Like a dinosaur! I got much better results from not so big sealed subs. The REL strata III worked quite well but was still a little slow. Quite a few people used to use those IIRC.
Mind you I have little experience of using integrating subs with a minidsp and having the ability to tune it so much there.
Sounds interesting. Using ported and sealed subs together, and getting both of the types of bass radiation patterns.
In the past I could never get ported subs (on their own) to integrate well with some Maggie 3 series . I used some big ones too that were tuned very low. They were just too slow. Like a dinosaur! I got much better results from not so big sealed subs. The REL strata III worked quite well but was still a little slow. Quite a few people used to use those IIRC.
Mind you I have little experience of using integrating subs with a minidsp and having the ability to tune it so much there.
It's the low-pass behavior of the subs that necessitates the type of integration. This is defined (and not alterable) in many cases, so you'd probably want to try and match that.....whatever it is.
Whether the sub is dipole or sealed-box is another aspect. I think it's preferable to use dipole subs, but box subs are much more available and easier to get started with.
Dave.
Thanks for the info. I see. So if your sub's own control had a 4th order LP, for example, the method of first order on the Maggies at their bass roll of point might work ok?
Would a PLLXO (single cap) be ok to use before the speaker power amp to get that 1st order HP or would you be better off using something like a minidsp?
This 1st order HP method you suggested obviously doesn't have as much filtering as if you rolled up the Maggies higher up, say at 80 Hz with a 4th order active HP. Is the former method sufficient in removing enough low frequencies in the signal to protect against excursion, and get a fair amount of higher max volume?
Appreciate dipole subs will integrate better than box ones. I tried an open baffle sub before in my system but it never worked well. Looks like you need quite a few very light drivers, and preferably a servo amp. That GR research sub setup isn't too cheap I guess..
A simple capacitor in front of your amplifier will yield the first-order slope, but that only works correctly if you're using the natural roll-off point of the Magnepan's.
If going up higher, like maybe 80Hz, then it's a different scheme and you'd need to adopt a different approach.
A low frequency first-order filter isn't going to help out too much on bandwidth-limitation relative to a 4th-order electrical filter at 80Hz. If a person is looking to play the main speakers a good bit louder than they're capable of driven full range, then the higher frequency/order crossover is preferred. But, (smaller) Magnepan's are limited in their SPL capability anyways, so you can quickly get to the point of diminishing returns.
Dave.
Thanks Dave.
Yeah that's what I thought. In that video I guess the 4th order active Hp he uses later on in the vid is providing a bit more max vol without distortion, but the small Maggies have limited vol anyways so probably not a huge different to using a first order at Maggies bass roll off freq as you suggest.
I was curious as to whether the distortion you can hear when he runs the Maggies full range at the start of the vid is all due to max panel excursion etc, or if the speaker amp might be clipping a bit too. Guess there is no way to know for certain without measurements.
Thanks for the first order HP tip at the Maggie bass roll off point. It might provide a touch more max vol, less congestion, a bit of driver protection, and might also make sub integration easier. I'll be trying that in the future with the bigger Maggie models. I would assume that the bass extension of the bass panel when run like that is similar or not too much less than when the speakers are run full range, which is handy. Might not need a sub so much like that with a bigger model.
Can use a Pllxo too which is cheap and sounds good.
I've read your comments with interest on this ... when you've referenced crossovers you're referring to analog not digital implementations, correct?
with regards,
Yes either will work. Digital XO like a minidsp etc or an analogue active XO, or a PLLXO (passive line level XO) which in this case (as it's just a first order high pass required) is just a small line level cap in between pre and power amp. The Pllxo would be my preference as you can use a polypropylene or polystyrene film cap. Very good sound and cheap compared to an active XO that would be comparable.
I bumped into a line level Xover aficionado on high eff. a few days back
never tried them myself
thanks!
regards,
Welcome. Did that guy mean the passive line level type (PLLXO)? I played with these quite a bit a few years ago. They can be very good for cheap money.
One problem I found when biamping the older Maggie MGIIIas and 3.3Rs (which require a 3rd order low pass on the bass) is that when using an HP PLLXO, you can get phase matching issues if you are using a digital crossover for the low pass as digital XOs have a delay. The high pass comes in just before the low pass, although you can phase match it up a bit better by playing with the delay on the digital XO. Although I never tried it (but want to) using a 3rd order Active XO with opamps like a Marchand for the low pass might be much better than a digital XO as there is miniscule delay I believe. You can't easily use a 3rd order low pass PLLXO to complement the high pass PLLXO as there is too much insertion loss with 3rd order.
With the current *.7 Maggies (for biamping) I would assume it would be ok to use a PLLXO for the low pass too (as the speakers use all first order slopes), and you could then adjust the level balance with a pot on the high pass.
he stressed that PLLXO was the 'clear' winner of crossovers, money no object
unless I read him wrong
all I could respond with was that I miss tone controls, which totally misses the point of course ... as it turns out some find my sparkling wit rather dull, knuckle dragging troglodyte that I am
<> \_(ツ)_/ <>
with regards,
Haha. I miss tone controls sometimes too :-)
I used to use Wima FKP1 caps (film and foil polypropylene) for the high pass PLLXO. Cost about $3 each and sounded v good. More exotic cap options would have improved things more.
I never got as good sound as a PLLXO when using an active XO or digital XO on the high pass instead.
No, either way (analog or digital) can work.
Dave.
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