What's wrong with subs?
Posted by: Rockingdoc on 05 January 2004
Being a fanatical purist type (why I else would I be here), I've previously avoided sub-woofer's like the plague.
Anyhoo, for our New Year's Eve house party, I decided to beef up the sound to suit the teenagers dance music and borrowed a sub. Nothing sophisticated, just a nice 15" driver in a ported 100 litre cab, 200 watt amp and a crude bypass filter.
It sounded great for the party, pictures were shaken from the walls, and everyone said nice things about the system.
The problem now is that my system sounds anaemic and bass light. We do have a big room, and I think I want a sub.
Can anyone advise of likely difficulties, will I get fed up with a sub? What should I buy, always REL?
The problem
Anyhoo, for our New Year's Eve house party, I decided to beef up the sound to suit the teenagers dance music and borrowed a sub. Nothing sophisticated, just a nice 15" driver in a ported 100 litre cab, 200 watt amp and a crude bypass filter.
It sounded great for the party, pictures were shaken from the walls, and everyone said nice things about the system.
The problem now is that my system sounds anaemic and bass light. We do have a big room, and I think I want a sub.
Can anyone advise of likely difficulties, will I get fed up with a sub? What should I buy, always REL?
The problem
quote:
Originally posted by Andrew B.:
PS. Paul, you don't need an extra amp for an active sub like the RELs (and you should avoid the passive ones).
A
I presume you mean cheap commercial passive subwoofers? I had great success with DIY coupled cavity passive subwoofers (using 10" Seas units) with my Kans.
Flat to 20Hz @ 100dB (-3dB at 16Hz) A bit big and massively heavy at 21" cubed (x2). They make good large pot plant stands for those with WAF worries.
I would agree that the coupled cavity subs might not suit floor standers that go much lower. None I've seen have a suitably low upper roll-off point.
Mine each had single 4" exit ports. Which certainly allowed non-turbulent flow compared with any normal speaker reflex port. Though I radiused the exit pipe rim for appearance I noted no difference.
Other than with Kans and similar sized boxes it is probably better to use good active subs. If you can afford two.
I still find it fascinating to hear that Mana stands, bigger amps and mains spurs can achieve subsonic bass from conventional speakers. Those who advocate such things have obviously never experienced really low bass. It may be that cleaning up the higher bass frequncies gives the impression that the bass goes deeper. Simply because the upper bass is no longer swamping the room quite so much as before.
The simplest test for your pet theories is to put on a good organ piece. What about a nice bit of Vierne? Can you feel anything but can't hear it? Thought not. 'Nuff said.
Nime
Everyone has the right to be wrong.
quote:
Originally posted by Matt F:
Incidentally, if a sub has very low distortion then if you play a test tone of less than 20Hz through it you should not be able to hear a thing (but strange things may start happening to your room!) – if you can hear anything then the sub is producing harmonic distortions.
Matt.
Purists should close their eyes...NOW!
My passive subs could (singly) give me bus travel sickness at (completely silent) low volume settings on a 30watt A&R A60 amp driven by an audio signal generator. There was still output at 7-8Hz and they were inaudible up to nearly 30hz when a soft sense of fluttering movement was just becoming audible as an airy purr. Below that they were completely silent. It was fun to walk the length of my 30ft listening room, down the open plan stairs and along the hallway with a low (just audible) tone on one subwoofer. You can really discover something about phase that way. I wonder why they say the A60 has bass roll-off?
Not bad for 2 x 10" Seas units, a couple of sheets of 3/4 MDF, some PVC drainpipe and David Purton's £5 "Coupled Cavity Subwoofer" booklet. They won't go loud because they are perfectly matched to Kans at 87dB/Watt. I saw over 105dB maximum on test of a single subwoofer at 20Hz. I still have the graph of the tests somewhere. Flat line from 20hz upwards to the -3dB roll-off for the Kans.
The coupled cavity system pumps a port (or ports) often with the unit completely hidden inside. As are mine. The unit sits in a two cavity system with long connecting internal port and single 4" diameter exit port. This is a much more efficient way of moving air than any sized membrane you care to choose. It starts and it stops dead without overhang. It doesn't need hundreds or thousands of watts to reach only 25-30Hz. It's major drawback is finding a design that rolls off naturally & early enough, without using a crossover when used with larger speakers. It matches small speakers like Kans effortlessly & maintains the speed of the smaller speaker perfectly. As long as you use two of them close to the Kans.
The purists can open your eyes again now.
Nime
Everyone has the right to be wrong.
Great thread
I'm a sub believer, that is in lieu of large expensive floorstanders that'll do a similar job of reaching down to infrasonics in the one box a-la DBL's etc.
My much loved SBL's do a more than reasonable job, as Naim quote they reach down to 30Hz in room, and I've got one review where they achieve 25hz at minus 6db in room - not bad for an 8 unit, no doubt helped by the close to the boundary placement. However, much has been made of the increased sense of ambience etc when the lower harmonics are correctly reproduced by a full bandwidth system, and as been pointed out, Pipe Organ and such, let alone HT sound effects go much lower than 25hz.
Hence, one needs the likes of DBL's,,,, or,,, a good sub IMHO.
Trouble is, I'm still waiting for Naim to produce something. Heh, it's on my 2004 wish list.
I'm curious as to how well the new/older Velodynes do on music. I've heard that they are supreme on HT, but not the most musical of subs - well at least that's what my Naim dealer tells me, but I've only heard one in a HT setup at a friends house - amazing, (HGS15) but I have no idea how they perform on music. Also, are the push pull M&K's as good as the velodynes, or better, or just different. I haven't heard any of them. They are available here, but trying to get a decent dem is like looking for a needle in a haystack, unless one is content to get a demo of explosions, car crashes etc via the ubiquitious HT.
Just curious.
Richard, are you reading this - we're all hanging out for a killer Naim sub..
Happy New Year to all
Best
John...
Populist thinking exalts the simplistic and the ordinary
I'm a sub believer, that is in lieu of large expensive floorstanders that'll do a similar job of reaching down to infrasonics in the one box a-la DBL's etc.
My much loved SBL's do a more than reasonable job, as Naim quote they reach down to 30Hz in room, and I've got one review where they achieve 25hz at minus 6db in room - not bad for an 8 unit, no doubt helped by the close to the boundary placement. However, much has been made of the increased sense of ambience etc when the lower harmonics are correctly reproduced by a full bandwidth system, and as been pointed out, Pipe Organ and such, let alone HT sound effects go much lower than 25hz.
Hence, one needs the likes of DBL's,,,, or,,, a good sub IMHO.
Trouble is, I'm still waiting for Naim to produce something. Heh, it's on my 2004 wish list.
I'm curious as to how well the new/older Velodynes do on music. I've heard that they are supreme on HT, but not the most musical of subs - well at least that's what my Naim dealer tells me, but I've only heard one in a HT setup at a friends house - amazing, (HGS15) but I have no idea how they perform on music. Also, are the push pull M&K's as good as the velodynes, or better, or just different. I haven't heard any of them. They are available here, but trying to get a decent dem is like looking for a needle in a haystack, unless one is content to get a demo of explosions, car crashes etc via the ubiquitious HT.
Just curious.
Richard, are you reading this - we're all hanging out for a killer Naim sub..
Happy New Year to all
Best
John...
Populist thinking exalts the simplistic and the ordinary
quote:
Originally posted by Johns Naim:
I'm curious as to how well the new/older Velodynes do on music. I've heard that they are supreme on HT, but not the most musical of subs - well at least that's what my Naim dealer tells me, but I've only heard one in a HT setup at a friends house - amazing, (HGS15) but I have no idea how they perform on music. Also, are the push pull M&K's as good as the velodynes, or better, or just different.
John - I used to own a Velodyne HGS15 so I can speak from experience here. When I got it I was using a pair of KEF Ref 2-2's as main speakers - pretty good to around 35Hz in room.
Because I use an AV processor I was able to do some easy comparisons of the HGS15 against the Ref 2-2's - I could switch between the 2-2's on their own and then bring the sub in using an 80Hz roll off i.e. <80Hz to sub, >80Hz to KEF's. I was amazed at how much tighter/faster/cleaner the bass sounded when letting th HGS15 handle everything below 80Hz - sure I knew it would play deeper but the cleaness was amazing.
So, basically, the HGS15 played bass (below 80Hz) much cleaner than a not inexpensive (£1750) hifi speaker. This is down to the amazingly low distortion (which itself is down to great engineering - servo control and a massive 1250 watts RMS amplifier). Low distortion equals superb musical performance IMO.
The M&K push pulls are fine subs but they aren't in the same league as the Velodyne HGS's - the M&K's have the output but simply can't play as cleanly as the HGS's.
What's interesting to note here is that the new THX Ultra II specs for subwoofers require subs to produce 105dB at 20Hz with no more than 4% distortion. Hardly any subs have Ultra II certification and it's the very low distortion requirements that will trip them up - the Velodyne HGS15 and HGS18 both attained Ultra II certification.
Matt.
p.s. sorry to mention "THX" on this mainly hifi forum
I guess the main reason for asking about how well the Velodynes and M&K's do on music, is to try and figure out how well they would integrate with my SBL's. As any SBL fan will no doubt be pleased to mention, they have tremendously tight, articulate, detailed, 'fast' bass, with little or no overhang or bloat. HT has music soundtracks, sure, but they mostly take a back seat to dialogue, effects etc, that being the main event and the music the add-on for emotional impact etc. Without the 'distraction' of video, ones audio senses become much more critical on music/HiFi IMHO.
My Naim dealer advocated the REL, which they stock, and in particular the Strata 111, being sealed, as the best/most likely match to an SBL. Apparently they have had the Velodynes in for test etc in the past, and sold a few, but generally didn't think they were as good as the REL's musically, i.e. for music reproduction purposes.
However, I find the Velodyne attractive because it is a sealed box design, (which should give excellent transient response) it goes VERY low in terms of extension (the bigger REL's will go there too, but they're ported designs albeit with some form of coupled cavity loading to 'tighten' the sound as I understand it) they have very low distortion coupled with high power handling, and er, they look nice in timber finish, and aren't a hugely excessive box re physical size.
The M&K appears to do well on spec, however the finish is not as appealing to me re being a plain painted black ash - THX 350 & 5000.
The thing that DOES attract me to the REL's is the way one can couple both high and line level outputs at the same time, hence it can be used for music to extend the range of the main speakers, and in HT mode, will extend the bass of the main left and right speakers, as well as providing LFE from the AV processor via the separate low level feed. Neat.
I'm not aware of being able to do that with the Veodyne or M&K's. Is it possible? It makes a lot of sense to me in terms of value for money to be able to use a sub with individual connections for both HiFi and HT, as well as augmenting the performance in both disciplines.
It's certainly a wiring/usuage scheme I find very attractive.
On specs though, the latest range of DD Velodynes look quite something - at least if their website is anything to go by.
As a large sealed box unit, but not excessively big physically, with a very extended and low distortion response, it is very appealing, with the caveats of how it could be wired re the flexibility of a REL, and how it would perform as a match with SBL's.
It's interesting that they still use sealed box designs, rather that the reflex ports of others.
Here in Melbourne, there is a fairly new company called Whise, which makes subs from smallish domestic, up to huge, and I mean HUGE professional units. The drivers, amps, cabinet work etc is all done/built locally, and they use a patented method of bass loading called PAM or parametric acoustic modelling. This has been developed in conjunction as I understand it with a professor at Monash University, and Dr Thiele of loudspeaker design fame.
Interestingly, the speaker is hidden inside the box; it appears that two internal labyrinths 'feed' the output from both the front, and rear of the driver, separately, and summing them at an output port. They claim vanishingly low distortion, very low response, and coupled with very high SPL output. I've heard them, and most impressive indeed, again, not having been able to compare them to anything else in an A/B situation, it's difficult to make objective comparitive judgements. The only drawback from my point of view is that the labyrinth does result in a very large box, and I'm not sure how they would compare to a sealed box re transient response etc. I mention them, not as a 'red herring' as it were, but out of curiousity - I wonder if some of our resident speaker gurus would like to take a look at the site, and make some comment on the technology, as I lack the technical knowledge to do so, but find the arguments for it quite persuasive. Apparently they are selling extremely well, and are fast becomming highly regarded on the US HiFi/HT scene.
Goodness, don't things get complicated sometimes - Heheh, so many choices, if ONLY Naim would bring out a killer sub that would be a perfect match to the rest of their speaker range, the problem could be solved
Warmest Regards
John...
Populist thinking exalts the simplistic and the ordinary
My Naim dealer advocated the REL, which they stock, and in particular the Strata 111, being sealed, as the best/most likely match to an SBL. Apparently they have had the Velodynes in for test etc in the past, and sold a few, but generally didn't think they were as good as the REL's musically, i.e. for music reproduction purposes.
However, I find the Velodyne attractive because it is a sealed box design, (which should give excellent transient response) it goes VERY low in terms of extension (the bigger REL's will go there too, but they're ported designs albeit with some form of coupled cavity loading to 'tighten' the sound as I understand it) they have very low distortion coupled with high power handling, and er, they look nice in timber finish, and aren't a hugely excessive box re physical size.
The M&K appears to do well on spec, however the finish is not as appealing to me re being a plain painted black ash - THX 350 & 5000.
The thing that DOES attract me to the REL's is the way one can couple both high and line level outputs at the same time, hence it can be used for music to extend the range of the main speakers, and in HT mode, will extend the bass of the main left and right speakers, as well as providing LFE from the AV processor via the separate low level feed. Neat.
I'm not aware of being able to do that with the Veodyne or M&K's. Is it possible? It makes a lot of sense to me in terms of value for money to be able to use a sub with individual connections for both HiFi and HT, as well as augmenting the performance in both disciplines.
It's certainly a wiring/usuage scheme I find very attractive.
On specs though, the latest range of DD Velodynes look quite something - at least if their website is anything to go by.
As a large sealed box unit, but not excessively big physically, with a very extended and low distortion response, it is very appealing, with the caveats of how it could be wired re the flexibility of a REL, and how it would perform as a match with SBL's.
It's interesting that they still use sealed box designs, rather that the reflex ports of others.
Here in Melbourne, there is a fairly new company called Whise, which makes subs from smallish domestic, up to huge, and I mean HUGE professional units. The drivers, amps, cabinet work etc is all done/built locally, and they use a patented method of bass loading called PAM or parametric acoustic modelling. This has been developed in conjunction as I understand it with a professor at Monash University, and Dr Thiele of loudspeaker design fame.
Interestingly, the speaker is hidden inside the box; it appears that two internal labyrinths 'feed' the output from both the front, and rear of the driver, separately, and summing them at an output port. They claim vanishingly low distortion, very low response, and coupled with very high SPL output. I've heard them, and most impressive indeed, again, not having been able to compare them to anything else in an A/B situation, it's difficult to make objective comparitive judgements. The only drawback from my point of view is that the labyrinth does result in a very large box, and I'm not sure how they would compare to a sealed box re transient response etc. I mention them, not as a 'red herring' as it were, but out of curiousity - I wonder if some of our resident speaker gurus would like to take a look at the site, and make some comment on the technology, as I lack the technical knowledge to do so, but find the arguments for it quite persuasive. Apparently they are selling extremely well, and are fast becomming highly regarded on the US HiFi/HT scene.
Goodness, don't things get complicated sometimes - Heheh, so many choices, if ONLY Naim would bring out a killer sub that would be a perfect match to the rest of their speaker range, the problem could be solved
Warmest Regards
John...
Populist thinking exalts the simplistic and the ordinary