TP1 Posted November 20, 2018 Share Posted November 20, 2018 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 21, 2018 Share Posted November 21, 2018 On 20/11/2018 at 7:10 AM, Ittaku said: drivers don't have an awful lot of excursion. 40mm of "linear" travel is not too bad IMO. Link to comment Share on other sites More sharing options...
Ittaku Posted November 21, 2018 Author Share Posted November 21, 2018 30 minutes ago, davewantsmoore said: 40mm of "linear" travel is not too bad IMO. It's 30mm of linear and 45 total according to the latest product brief. http://www.rythmikaudio.com/DS1500driver.html Compared to the 65mm/78mm of the SB16 driver, it's a heck of a lot less. Link to comment Share on other sites More sharing options...
Ittaku Posted November 21, 2018 Author Share Posted November 21, 2018 Audiosalon got back to me and said the G25HP isn't available in Australia. Back to holding pattern for now. Thanks everyone for your input and suggestions. Link to comment Share on other sites More sharing options...
AccuTidal Posted November 21, 2018 Share Posted November 21, 2018 Interesting readings.... The Magico Q-SUB 15 has always been in my wish-list. Actually still is..., if it was not for our $$$ being so low and the asking price tag. There is one in W.A and the owner is a Medical Practitioner. I wonder how many of you had actually heard it first hands? Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 21, 2018 Share Posted November 21, 2018 4 hours ago, Ittaku said: It's 30mm of linear and 45 total according to the latest product brief. Oh, ok.... sorry. I got +/- 20mm xmax from a quick google (maybe too quick). Link to comment Share on other sites More sharing options...
Ittaku Posted November 22, 2018 Author Share Posted November 22, 2018 (edited) I got a response directly from Magico, after asking for more detailed frequency response plots and peak/continuous program output ratings at different frequencies: Quote Thank you for your interest in the Magico QSUB15. The QSUB15 by design will provide incredibly fast and detailed low bass performance in union with the main L/R loudspeakers in your system. The QSUB15 features a Magico designed 15” bass driver (x2), all aluminum fully braced sealed enclosure, purpose built power amplification and an extremely complex electronic crossover and DSP control center which when setup properly will allow for seamless integration with your existing L/R loudspeakers. We do not provide test specifications or measurements completed under laboratory conditions as they are all subject to change based on room interaction and the low frequency capability of the existing L/R speakers operating in the same space. Attached please find a copy of the universal owner’s manual for the QSUB15, QSUB18 and SSUB which provides a comprehensive overview on the features of the internal electronic crossover and DSP control center. If you like, please share details on your existing listening room and system components including loudspeakers for our review and comment on how the QSUB15 will integrate into your system. Can't say I'm impressed. I'd already gotten a copy of their manual as well, and there was nothing of substance in it in terms of specifications above the advertising blurb. Edited November 22, 2018 by Ittaku 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 22, 2018 Share Posted November 22, 2018 I sent this message through the Magico online contact form: Quote Hi. I'm interested in the Q-sub 18. I see you have specified 136dB @ 20Hz @ 1% THD. Was this in a room (gain)? What else can you tell me about the data, so I can directly compare to other subs? Here is the email I received back: Quote Thank you for your interest in the Magico QSUB18. The measurements on our website are reported from laboratory test conditions and are subject to change depending on the interaction of the room and the main L/R speakers operating in the same space. The QSUB18 by design will provide incredibly fast and detailed low bass performance in union with the main L/R loudspeakers in your system. The QSUB18 features a Magico designed 18” bass driver (x2), all aluminum fully braced sealed enclosure that doesn’t store energy, purpose built power amplification and an extremely complex electronic crossover and DSP control center which when setup properly will allow for seamless integration with your existing L/R loudspeakers. Attached please find a copy of the universal owner’s manual for the QSUB15, QSUB18 and SSUB which provides a comprehensive overview on the features of the internal electronic crossover and DSP control center. If you like, please share details on your existing listening room and system components including loudspeakers for our review and comment on how the QSUB18 will integrate into your system. Here is the response I have sent back: Quote Hi Peter. Thanks for the reply. Is it possible for someone to directly address my question? I am looking at the maximum output of subwoofers at around 20Hz .... You have specified 136dB @ 20Hz @ 1% THD. Can you tell me about the "lab test conditions" you mentioned? There must be a lot of "room gain" on this measurement to be able to achieve such impressively high SPL at such low distortion ..... If I'm to directly compare your subwoofer to other subwoofers, then I need to know about this - as other subwoofers are typically reported in 2pi space. Similarly. If your subwoofer makes 136dB @ 20Hz @ 1% distortion ..... then how loud is it at 10% distortion? 50% distortion? Simple physics (pure piston excursion for pressure) says it is unlikely to make a lot more than 136dB under any circumstances.... so the distortion spec is a little confusing. I hope you can help. I'm sure this subwoofer sounds wonderful .... but I cannot work out how many my cinema would need vs, other subwoofers ..... As you would understand ~10dB "room gain" differences will translate to potentially many multiples of subwoofers being specified. If I were to purchase 8 of your (or a competitor) subwoofers per cinema, when I only needed 4 .... per cinema .... You can appreciate this is would be a very very expensive mistake. Thanks in advance. --- 3 Link to comment Share on other sites More sharing options...
Ittaku Posted November 23, 2018 Author Share Posted November 23, 2018 1 hour ago, davewantsmoore said: I sent this message through the Magico online contact form: Here is the email I received back: Here is the response I have sent back: Sounds like just about the same marketing drivel I got. Their response is too guarded to put any faith in their ability to defy the laws of physics. Link to comment Share on other sites More sharing options...
Red Spade Audio Posted November 23, 2018 Share Posted November 23, 2018 I'd suggest their response means one of two things: 1. The person answering doesn't know 2. They don't think it's in their best interest to answer directly It's usually quite easy to spot the difference between a DIYer fishing for information and a customer working through the questions they need answered before they are ready to buy. 2 Link to comment Share on other sites More sharing options...
Ittaku Posted November 23, 2018 Author Share Posted November 23, 2018 2 minutes ago, Red Spade Audio said: It's usually quite easy to spot the difference between a DIYer fishing for information and a customer working through the questions they need answered before they are ready to buy. Only I'm both... 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 23, 2018 Share Posted November 23, 2018 2 hours ago, Red Spade Audio said: 1. The person answering doesn't know 2. They don't think it's in their best interest to answer directly Indeed... or a combination of both. The people who do know .... likely also understand that it's not "not in their interests". Link to comment Share on other sites More sharing options...
almikel Posted November 23, 2018 Share Posted November 23, 2018 great thread... An audio colleague says often, "there's nothing new in audio transducers". IMHO the innovations in speakers in the last decades have been: Peter Walker's ESL 57s. The rotary sub Danley's Synergy and Tapped Horn Excluding the rotary sub, normal subs are still constrained by Hoffman's Iron Law, and Magico can't get around that in this universe (ie the laws of physics) using dynamic drivers. The rotary sub is an amazing take on the challenge of low bass - I've not heard one, but they can reach to DC. cheers Mike Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 25, 2018 Share Posted November 25, 2018 On 23/11/2018 at 11:40 AM, Ittaku said: Sounds like just about the same marketing drivel I got. Oh, wow. I just noticed where you posted that. It's "word for word" in places. FWIW, asking for a frequency response chart can be problematic, as unless then measurement is outside, it will say a lot more about the room, than the woofer (or at least, we won't be able to tell either way) Link to comment Share on other sites More sharing options...
bzr Posted November 25, 2018 Share Posted November 25, 2018 On 23/11/2018 at 12:28 PM, Ittaku said: Only I'm both... You mentioned Wilson Benesch Torus Infrasonic Generators. They have the accolades science etc. The importer/distributor you mentioned also said to me to back the ones I have & not the Magico when I asked.... Link to comment Share on other sites More sharing options...
Ittaku Posted November 25, 2018 Author Share Posted November 25, 2018 Just now, bzr said: You mentioned Wilson Benesch Torus Infrasonic Generators. They have the accolades science etc. The importer/distributor you mentioned also said to me to back the ones I have & not the Magico when I asked.... Yeah they looked interesting. I did look into them extensively after that. However, while they're amazing and compact on paper, the are also not loud enough for my application to replace my current setup, even if I were to get multiples, and they are rather pricey too. Link to comment Share on other sites More sharing options...
bzr Posted November 25, 2018 Share Posted November 25, 2018 1 minute ago, Ittaku said: Yeah they looked interesting. I did look into them extensively after that. However, while they're amazing and compact on paper, the are also not loud enough for my application to replace my current setup, even if I were to get multiples, and they are rather pricey too. ?? not loud enough...are you trying to bash 747's back into the departure lounge???? Link to comment Share on other sites More sharing options...
bzr Posted November 25, 2018 Share Posted November 25, 2018 (edited) Also half price of Magico & come with 180 watt amps... Edited November 25, 2018 by groot Link to comment Share on other sites More sharing options...
Ittaku Posted November 25, 2018 Author Share Posted November 25, 2018 1 minute ago, bzr said: ?? not loud enough...are you trying to bash 747's back into the departure lounge???? Yes? Link to comment Share on other sites More sharing options...
bzr Posted November 25, 2018 Share Posted November 25, 2018 good luck, I'm outa here before you depart the departure lounge.... Link to comment Share on other sites More sharing options...
Ittaku Posted November 25, 2018 Author Share Posted November 25, 2018 Maybe I misread something then... You all seem to think these things are super loud at 20Hz? I'll go back and reread. Link to comment Share on other sites More sharing options...
Ittaku Posted November 25, 2018 Author Share Posted November 25, 2018 (edited) This was the part in the specifications of note in the product brochure when I downloaded it: Quote Maximum SPL 100dB @ 1-Meter Assuming the documentation is correct, and it wasn't meant to say sensitivity, 100dB is not very loud. The interesting thing is the website says it's 100dB sensitivity, NOT maximum SPL. Guess I need to email them for clarification... Sent. Let's see what they have to say. Edited November 25, 2018 by Ittaku Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 25, 2018 Share Posted November 25, 2018 2 hours ago, Ittaku said: website says it's 100dB sensitivity Must have lots of direct radiators, or a horn, for this to happen at low frequencies. Link to comment Share on other sites More sharing options...
Ittaku Posted November 25, 2018 Author Share Posted November 25, 2018 11 hours ago, davewantsmoore said: Must have lots of direct radiators, or a horn, for this to happen at low frequencies. Indeed, so unfortunately this manufacturer also falls into the same category as Magico for not having enough information to work off, though there is slightly more from them. I'm reasonably sure the 100dB SPL max figure is the correct one, making this a relatively compact sub (considering its 18" driver) but not particularly loud. Strangely all the much cheaper manufacturers give you loads of information and measurements, yet these ultra expensive ones do not as though they know their market is based on money and rave reviews primarily, maybe listening secondarily, and not information. Rel (with their G25) and Wilsonaudio (with their Thor's hammer) seem the stand out exceptions in the "audiophile" price brackets with a little more information, but even they don't provide anywhere much information as the very affordable SVS and PSA offerings. 1 Link to comment Share on other sites More sharing options...
davewantsmoore Posted November 26, 2018 Share Posted November 26, 2018 Ignoring the room gain (which can be significant, but shouldn't be assumed) ... An direct radiator 18" woofer need to move the following distances to make 100dB 40Hz ~2mm 20Hz ~8mm 10Hz ~32mm 5Hz ~128mm 2.5Hz ~512mm As you drop an octave, to keep the same SPL you need to move 4 times as much. If they have settled on "100dB" ... then a high excursion 18" driver could have constant output down to <10Hz (before accounting for room gain). So this seems about right-ish. Link to comment Share on other sites More sharing options...
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