bhobba Posted August 3, 2013 Posted August 3, 2013 (edited) Hi Guys In another thread the issue of exactly how loud an ML1 will go came up. I personally have heard them reach FRIGHTENING levels without distress. Mac 501's that clip at about 1.2k clipped and still no distress. Anyway thought I would open it up for discussion and hopefully Mike can chime in with a few technicalities about what they are capable of volume wise. Thanks Bill Edited August 3, 2013 by bhobba
hyper Posted August 3, 2013 Posted August 3, 2013 Never heard ML1s bill but if a bookshelf can clip a pair of 501 without breaking a sweat that's impressive!
davewantsmoore Posted August 3, 2013 Posted August 3, 2013 (edited) Sure, the driver will survive 1.2kw very short term.... You'd want to keep away from < 150hz though if you don't want to break something :-S Distress is a very subjective term. It's surprising how much we "won't notice". When Mike chimes in I hope he can give us a measurement of 1.2kw VS the ML1. I'd be interested in how much SPL they can create when operated above xmax (sims won't tell us with any accuracy). The largest amplifier I have ever used with this driver is 300w. I didn't push it either. I've not bothered with much past xmax @ 100hz .... 3.5mm excursion on these drivers is pretty large IMO. They seem very robust, but I don't think they sound great even at xmax... why go further? (Rhetorical of course. "Further" is fun). Edited August 3, 2013 by davewantsmoore
bhobba Posted August 3, 2013 Author Posted August 3, 2013 Distress is a very subjective term. It's surprising how much we "won't notice". Again Dave you hit it in one. At those levels you simply don't notice it. Bob Smith at Aether Audio used to use a Seas Magnesium because they could take more power without distress. But he switched to a cheaper Chinese drivers because at that level you simply cant hear it - it produced more measurable distortion but it was simply inaudible with your eardrums about to burst. He also thinks he is the only one crazy enough to feed the type of power his speaker could take - which was MASSIVE - he used a waveguide and padded the tweeter down so it could take a huge amount of power - interestingly often its tweeters that blow if you feed speakers too much power. Anyway its really up to Mike to supply the technicalities and hopefully he can chime in when he gets a bit of time. Thanks Bill
Lenehan Audio Posted August 3, 2013 Posted August 3, 2013 Sure, the driver will survive 1.2kw very short term.... You'd want to keep away from < 150hz though if you don't want to break something :-S Distress is a very subjective term. It's surprising how much we "won't notice". When Mike chimes in I hope he can give us a measurement of 1.2kw VS the ML1. I'd be interested in how much SPL they can create when operated above xmax (sims won't tell us with any accuracy). The largest amplifier I have ever used with this driver is 300w. I didn't push it either. I've not bothered with much past xmax @ 100hz .... 3.5mm excursion on these drivers is pretty large IMO. They seem very robust, but I don't think they sound great even at xmax... why go further? (Rhetorical of course. "Further" is fun). Hi Dave yes indeed the ML1's can handle the full transient output of the Mac501's ! let me just qualify that a bit , this is with material that does not push the bass driver above MAX excursion (where not talking about Linear Xmax here) if you played say Rage against the machine you'd end up with the bass diaphragm in you r lap of course. Specifically on the track Matilda , Harry belefonte Live at Carnegie Hall I was listening one day quite loud with my eyes closed and suddenly could hear distortion ! I opened my eyes and here are the Mac501 powergard lights continuously flicking on and off. The audible distortion was being produced by the Mac's running out of transient power which I think is around 1200 watts 8ohms ( IHF International 20ms Burst rating) I need to check that figure but I think it's right. The continuous RMS output of the 501's into 8ohms is 720watts per channel. How loud were they playing at that time I don't know but bloody loud with subjectively Zero distortion until the amps started distorting. When I get some time I'll measure the transient SPL at the listening chair . Of course the drivers aren't taking all that power as the Xovers simply dole out a specific recipe to them and as we all know passive component aren't 100% efficient so absorb some of the amplifier energy this is why they are SO SO critical. Regards Mike Lenehan LenehanAudio 1
davewantsmoore Posted August 3, 2013 Posted August 3, 2013 Oh also, sorry everyone. My dyslexia was playing up when I typed the name of the driver shown in the pictures. It's supposed to be 832873 (just in case anyone thought it was a sham).
davewantsmoore Posted August 3, 2013 Posted August 3, 2013 MAX excursion (where not talking about Linear Xmax here) Cool, thanks Mike. What value do you use for (xlim) max excursion? .... The manufacturer doesn't specify. I've never attempted to find it with an amplifier. My fingers tell me it can't be more than 5mm ?!?! I have done a lot of investigation around xmax... but testing at these levels takes a lot of effort ... the driver is reasonably badly behaved.... and it's really repeating work others have done.
hochopeper Posted August 4, 2013 Posted August 4, 2013 I agree harmonic distortion within the driver's excursion limit is not likely to be a problem, but that's really stating the obvious well known truth, isn't it? That part of the issue is always going to relate to the bandwidth and energy in the bass frequencies. That limitation is only part of the problem though I believe. I do not agree that there is no issues going on, they may not be obvious until you hear a speaker with drastically different design approach. I don't think this is an issue with any specific speaker but with the two way compact speakers of any make/design. Please don't take any of the above as a criticism of Mike's designs at all, this conversation came up because of my assertions about the limitation of a speaker format so I felt like I should comment. I've commented on one of the effects that I think is going on in Anthony's thread and I have previously mentioned it previously in the ML1 review thread, though no-one noticed it amongst the noise in that thread . Chris
Lenehan Audio Posted August 4, 2013 Posted August 4, 2013 Cool, thanks Mike. What value do you use for (xlim) max excursion? .... The manufacturer doesn't specify. I've never attempted to find it with an amplifier. My fingers tell me it can't be more than 5mm ?!?! I have done a lot of investigation around xmax... but testing at these levels takes a lot of effort ... the driver is reasonably badly behaved.... and it's really repeating work others have done. Hi Dave you can nut Xmax yourself by simply subtracting the magnetic gap from the Voice coil length (only for overhung voicecoil designs) in the case of the ML1 it's 7mm Peak to Peak or Xmax 3.5mm. There are problems with just designing a driver with huge Xmax. Distortion at upper frequencies suffers, mass increases and the driver gets slowed down. Coil inductance rises to unacceptable levels at higher frequencies if the design is to0 overhung. This would mean a totally different Xover . Not a solitary thing in loudspeaker design can be considered in isolation, The catchword with Loudspeaker design is COMPROMISE. The new ML1Limited will use a different Bass driver so of course it will build on the ML1 experience but really be a new speaker. Regards Mike Lenehan
A J Posted August 4, 2013 Posted August 4, 2013 Totally non-technical - but I used to turn up our loungeroom ML1's driven by Bel Canto REF1000's while we were in the pool. It was impressive hearing the cure blasting at full volume, people were always amazed that that much sound was coming out of sleakers that looked so small. I also had a great session playing the album Touch by Yello. I had to go around the ground floor of our house and blu-tack all the window panes to stop them rattling, also had to do the same on all the artwork we had on the walls. IMHO these speakers sound great right up to ear-splitting levels, I've never had any issues with overdriving or distortion. AJ 2
Volunteer sir sanders zingmore Posted August 4, 2013 Volunteer Posted August 4, 2013 I would think that in most systems the amp clips well before the speakers
hochopeper Posted August 4, 2013 Posted August 4, 2013 (edited) I would think that in most systems the amp clips well before the speakers I strongly disagree that this generalisation can be made for any vented two way full range speaker (limit the frequency range and you'll be right). For some music I agree that it may not be a huge problem. There is plenty that would prove that incorrect and it very much depends on the user's taste in music or movies. The assertion that high average level output can be done on a 2way full range speaker without bass augmentation is missleading. Especially if the tweeter is crossed low. Tweeter and upper midrange thermal handling, bass tuning for extension will all result in audible straining of the speaker on dynamics which many audiophiles will dismiss as just being 'loud' but is actually speaker crying for mercy. This is supported by Mike's suggestion in the ML1 review thread that there is a perceived advantage to having negative temp co resistors in the crossover. The exact same issues exist in the voice coil of the drivers. I'm out of this thread guys, this subforum isn't the place for this discussion, my comments were never constrained to specifically Lenehan speakers but all two ways and determining a realistic goal for speaker output levels at the listening position and relating that to output at speaker in a reasonable sized room, now it's all out of context and we're talking about only ML1, which needn't be the case and in fact like I said above with some neat work in the passive XO probably does ok if you keep the low freq away. Chris Edited August 4, 2013 by hochopeper
davewantsmoore Posted August 4, 2013 Posted August 4, 2013 (edited) I agree harmonic distortion within the driver's excursion limit is not likely to be a problem, but that's really stating the obvious well known truth, isn't it? Short version: Not really This is much more complex than it can seem on the surface. Traditionally, the drivers "linear excursion", is: "the voice-coil peak displacement at which the "linearity" of the motor deviates by 10%" So, if every driver was defined like that. Then they would all have (the same, 10% ?!) very similar distortion within their "linear excursion limit" ... but many drivers would then have very low "linear excursion limit", due to their poor motor linearity. You would simply be able to pick up a driver, move the cone 15mm with your finger .... see that manufacturer quoted "linear excursion" of 1mm (due to the motor linearity) ..... and you could decide "something is bad about this driver". ... but obviously the definition of "linearity" is key here. For example. Kippel data for the 8" HDS nomex, shows 10% BL deviation at about -4mm and +6mm cone position..... many other parameters are deviating by more than 10% at much smaller movements than "xmax". (Which Peerless cite as 4.5mm) Hi Dave you can nut Xmax yourself Sure, I can (as waffled about above, by me).... What I asked about though was "xlim". The limit. (Klippel call it Xprot) Have you discovered a value that you use for this? (EDIT: for the 832873) The reason I ask is I've never been game to find out (and really consider it academic too) .... but it would be an important thing to consider if hitting them with 1000w. :blowtorch: The new ML1Limited will use a different Bass driver I guess you won't tell us which one?! :bump: Edited August 4, 2013 by davewantsmoore
davewantsmoore Posted August 4, 2013 Posted August 4, 2013 I would think that in most systems the amp clips well before the speakers Like I tried (probably pretty badly) to say in my post above..... "clips" is poorly defined for speakers. ... So, yes. If you had 100w + modern drivers (like most people) .... and turned it up, up, up.... You would "clip" your amplifier first... before you did anything (obviously) bad to the driver (most modern drivers are very robust) ... but I think this sends very much the wrong message. Looking at 10w or 50w, input power (when using a, say, 100w amplifier) ..... The speakers are distorting a LOT more, than the amplifier.
davewantsmoore Posted August 4, 2013 Posted August 4, 2013 my comments were never constrained to specifically Lenehan speakers but all two ways Yes, me neither.... but I am still a fan of "2way" speaker. The less drivers possible the better IMO. OTOH, I also see "subwoofers" as essential (unless playback is very low level) .... so perhaps that means I like "3ways speakers".
Lenehan Audio Posted August 4, 2013 Posted August 4, 2013 Short version: Not really This is much more complex than it can seem on the surface. Traditionally, the drivers "linear excursion", is: "the voice-coil peak displacement at which the "linearity" of the motor deviates by 10%" So, if every driver was defined like that. Then they would all have (the same, 10% ?!) very similar distortion within their "linear excursion limit" ... but many drivers would then have very low "linear excursion limit", due to their poor motor linearity. You would simply be able to pick up a driver, move the cone 15mm with your finger .... see that manufacturer quoted "linear excursion" of 1mm (due to the motor linearity) ..... and you could decide "something is bad about this driver". ... but obviously the definition of "linearity" is key here. For example. Kippel data for the 8" HDS nomex, shows 10% BL deviation at about -4mm and +6mm cone position..... many other parameters are deviating by more than 10% at much smaller movements than "xmax". (Which Peerless cite as 4.5mm) Sure, I can (as waffled about above, by me).... What I asked about though was "xlim". The limit. (Klippel call it Xprot) Have you discovered a value that you use for this? (EDIT: for the 832873) The reason I ask is I've never been game to find out (and really consider it academic too) .... but it would be an important thing to consider if hitting them with 1000w. :blowtorch: I guess you won't tell us which one?! :bump: Hi Dave Xlim is going the be around 6 to 6.5mm for the ML1 bass driver ! total guess to be honest because where talking virtual destruction testing here. of course positive phase will be slightly more than inverted phase because of the yoke back plate. Regards Mike Lenehan
Paul Spencer Posted August 5, 2013 Posted August 5, 2013 The trouble with the mathematical xmax is that it doesn't always capture the performance well, with some behaving much better at that point. Some drivers are really pushing the suspension system and some are more linear at xmax. It can also be specified as the 70% BL point. The TC Sounds LMS-R has a mathematical xmax of 25mm but due to the linear BL design a more true indication is 32 mm where BL drops to 70%. Yes, that is ONE WAY. So, some drivers are really pushing their limits at xmax - I believe Exodus Anarchy is such a driver, where the motor suits but the suspension is tested. Others can perform beyond their xmax. Some manufacturers also give a rating where distortion reaches 10% and it's a slightly bigger number than xmax.
davewantsmoore Posted August 5, 2013 Posted August 5, 2013 Hi Dave Xlim is going the be around 6 to 6.5mm for the ML1 bass driver ! total guess to be honest because where talking virtual destruction testing here. of course positive phase will be slightly more than inverted phase because of the yoke back plate. Regards Mike Lenehan Thanks Mike (about what I expected) AFAIUI (different manufacturers have varying definitions) "Xlim".... shouldn't damage a driver. Unless you really spank it at Xlim for a while. I've seen "XDamage". Klippel have "XProt"
bhobba Posted August 6, 2013 Author Posted August 6, 2013 (edited) I do not agree that there is no issues going on, they may not be obvious until you hear a speaker with drastically different design approach. I don't think this is an issue with any specific speaker but with the two way compact speakers of any make/design. Hi Chris I don't think anyone is claiming there are 'no issues' going on. What the claim is is a speaker like the ML1 can reach unbelievably frightening levels without having noticeable distress even when fed with an amp like the Mac's. There will be material that doesn't happen with and I have heard the ML1 hit its stops on some material, but the surprising thing is that material is not as common as you might think. Mike has a large music collection across quite a few genres at his factory and there are only few tracks that cause issues. ML1's have limitations compared to speakers like the ML3 with larger bass drivers but its power handing is not as big a limitation as you might think. I remember when Mike had a late prototype of the ML3 Reference at the DAC GTG about 3 years ago now it was compared to an ML1 Reference that was there. To me the ML3 Reference was clearly and obviously better in every area than the ML1. Someone suggested the ML1 may have been better than the ML3. Mikes eyes sort of went wide and he got up and said anyone that thinks the ML1 is better than the ML3 has rocks in their head. But things move on, and while we will not know for sure until its built, Mike is VERY confident the new ML1 Limited he is working on will easily account for the ML3 Reference. Not in low end grunt of course, and power handling with some material, but overall it will be better. Thanks Bill Edited August 6, 2013 by bhobba
Juicester Posted August 6, 2013 Posted August 6, 2013 it will be better. there's that word i was talking about!
Volunteer sir sanders zingmore Posted August 6, 2013 Volunteer Posted August 6, 2013 there's that word i was talking about! Mate, this is the Dorothy Dixer section of SNA. Please respect that 3
hochopeper Posted August 6, 2013 Posted August 6, 2013 (edited) I don't think anyone is claiming there are 'no issues' going on. What the claim is is a speaker like the ML1 can reach unbelievably frightening levels without having noticeable distress even when fed with an amp like the Mac's. There will be material that doesn't happen with and I have heard the ML1 hit its stops on some material, but the surprising thing is that material is not as common as you might think. Mike has a large music collection across quite a few genres at his factory and there are only few tracks that cause issues. ML1's have limitations compared to speakers like the ML3 with larger bass drivers but its power handing is not as big a limitation as you might think. It seems you're easily frightened Bill I think definitions of loud and noticeable are easily mixed up without a common reference. Lets talk about noticeable distortions for a bit. What is noticeable is, as with many things in audio, debatable. Additionally, as Mike says there is a mix of compromises in every design. The vented two-way speaker comes with a few compromises that are inherent in that format, Mike has clearly gone a long way towards minimising those relative to other speakers of this type with his crossover and cabinet designs that is to be applauded. I have done quite a bit of reading on distortion perception and perception of phase distortion, reflections and more ... and I've got quite a bit more reading and research ahead of me I am sure. Though for now I have come to the conclusion that the mix of compromises for a speaker for very high output levels needs a different approach to what I felt would be possible when looking at data for different designs. The envelope of the crest is important and just noticeable differences are exceedingly low on high output and add to that the distortion masking may in fact be reduced for high output also, which is counter intuitive. To say that there is no obvious distortions on the large crest/peaks is probably ok, I do think there will be some impact on the sound quality before they become obvious though. Obviously I'm fairly firm in an objective approach to audio reproduction systems, I've gone a quite a bit further than the typical objective guy though in terms of removing distortion and jitter and other effects that might otherwise be dismissed as inaudible by many. The level of understanding to take an entirely objective approach is not trivial and I'm not going to say that this approach is correct or that I'll get the mix right the first time, the system I'm doing at the moment has been in-progress for some time now and I've learned a lot since I started. Learning is a big part of the hobby for me as is the listening enjoyment. Getting both is important to me. Looking forward to meeting you guys at the amp GTG and will have a yarn in person with a lot less typing necessary! Hope I don't get chased out of the joint for my heretic objective ways though Chris Edited August 6, 2013 by hochopeper
gainphile Posted August 6, 2013 Posted August 6, 2013 How loud depends on how much LFE content. 40hz above are non issue of course but then comes Daft Punk. I really don't see how 5" or 6" driver can reproduce this truthfully. It would be fun to test though.
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