davewantsmoore Posted November 4, 2018 Posted November 4, 2018 14 hours ago, almikel said: subs usually need to cope with higher SPLs - especially with HT ????? He has implied his system is calibrated for reference - ie. full output will deliver 105dB per channel (or 115dB for the bass). If he never lifts the volume dial above -12.5dB .... then the PEAK SPL in the bass will never rise above 102.5dB. So in that case, 102.5dB is the correct subwoofer output to design for.
davewantsmoore Posted November 4, 2018 Posted November 4, 2018 14 hours ago, almikel said: dipole bass is too hard to get right Perhaps you are not looking at it in the right way(?!), people often over complicate it. At subwoofer frequencies the differences between a monopole and dipole source are surprisingly few.... and all of the same basic issues apply in general The dipole will excite room modes with a different (but not necessarily better or worse) strength to a monopole, depending on it's placement At low frequencies, the bass output will drop off faster than you want, and you will probably want some type of EQ to lift it up (the dipole just drops of faster than a monopole at LF) Dipole woofers will reach maximum excursion earlier than a monopole for the same SPL Dipole woofers need substantially less power to reach maximum excursion (but this only applies to an "open baffle", and not to two output of phase monopole that are arranged to form a dipole) Placement.... EQ..... excursion limits..... power limits .... these are just generic design issues.
davewantsmoore Posted November 4, 2018 Posted November 4, 2018 13 hours ago, Nada said: You might save a lot of time, some money and pain by paying for expert input It depends on what he wants help with. Design, or construction (or both). There are many published subwoofer designs which will work great... Why reinvent the wheel? (there might be a reason, but I don't see one yet). Of course, if you can't build a documented design confidently .... then having someone build something, is a good choice. 11 hours ago, Primare Knob said: and don't really need them. The reason to have multiple bass sources is not just one of SPL output. Multiple bass sources can address how room modes are excited. You seem very focused on getting a high quality result.... what is going to matter much much much more than what enclosure your build and what driver you use (within sensible reason) is where you place the subwoofer and how it excites the room. More than one subwoofer may excite the room a lot better. What I am saying is that your "don't really need them" could be flippantly disregarding the largest (by far) factor of your bass performance. Perhaps you have already worked out that 1 subwoofer will do a good enough job in that regard..... but you haven't mentioned that in this thread. Perhaps you cannot fit more than 1 subwoofer anywhere in your room..... that's totally understandable, and in that case limits your options nicely. 11 hours ago, Primare Knob said: Still have lots to learn, and likely gonna adjust my ideas once I understand things better. Go with a sealed box. Pick your "acceptable" box size ..... you know your output requirement ..... this will tell you which driver(s) you need. Build the box exactly as documented. 11 hours ago, Primare Knob said: I know, but that also takes away a lot of the learning path. Plus my stubbornness hasn't caved in yet The "learning path" is much more "practical" than "theoretical". If you're not prepared to build 5x subwoofers (design, build, test, redesign) and likely buy multiple drivers ...... then I'd advise you to shortcut that by building something that you know will work. If you want to increase the quality, then the focus needs to be on placement, EQ, and likely multiple woofers. If you have too much distortion, then this could also be a problem it it's extreme.... but the only solution to that is larger sized boxes, or larger number of boxes. Most people have practical limits for those, understandably.
Primare Knob Posted November 5, 2018 Author Posted November 5, 2018 The "learning path" is much more "practical" than "theoretical". If you're not prepared to build 5x subwoofers (design, build, test, redesign) and likely buy multiple drivers ...... then I'd advise you to shortcut that by building something that you know will work. If you want to increase the quality, then the focus needs to be on placement, EQ, and likely multiple woofers. If you have too much distortion, then this could also be a problem it it's extreme.... but the only solution to that is larger sized boxes, or larger number of boxes. Most people have practical limits for those, understandably. I am pretty confident that I can get even bass response over multiple seating positions using 2 subwoofers with my single row 3 seater (2 adults+2kids) configuration.Non the less, the best position sofar used in a single seat configuration is placing the subs half way the length of the room along the wall. With my future sofa on the way I tested it with the added estimated seating positions and this no longer seems to be ideal. Also the person sitting on both ends of the sofa are getting rather close to the subs, I have tested some new sub positions at the 1/4 width room position along the front wall. This does heavily accentuate the 35Hz room node I am having but and some other peaks at the Left and Right listen position, but no major dips. But I do end up with an EQ issues in the 45-70Hz range as I have to cut heavily for the L and R listen position, but not for the Centre listen position.This 1/4 position does have the room to build larger subs.I'll have to tweak the position a bit more and see if more than 2 subs are needed.
davewantsmoore Posted November 5, 2018 Posted November 5, 2018 1 hour ago, Primare Knob said: using 2 subwoofers Right, 2 is usually a lot more helpful than 1. (I thought you were only planning one) 1 hour ago, Primare Knob said: Also the person sitting on both ends of the sofa are getting rather close to the subs, I would not worry about this too much. As long as the subwoofer is well low pass filtered (eg. it is -6dB@80Hz, and the rolloff is 24dB/octave) ... then this shouldn't be a drama. 1 hour ago, Primare Knob said: I'll have to tweak the position a bit more and see if more than 2 subs are needed. Possibly not. If your room is rectangular-ish, then this calculator might give you some ideas. http://www.hunecke.de/de/rechner/lautsprecher.htm
almikel Posted November 6, 2018 Posted November 6, 2018 On 04/11/2018 at 9:56 PM, Primare Knob said: I believe that Isobaric designs have only one woofer in contact with the outside air, and one woofer in a sealed enclosure without contact with the outside air, to keep a constant pressure in the enclosure used for the other driver. On 04/11/2018 at 10:19 PM, Primare Knob said: But will it still be a di-pole if both driver move in the same acoustical direction? On 05/11/2018 at 9:15 AM, davewantsmoore said: No. My interpretation of what PK is saying is that he's proposing a sealed box with a driver on the front and the rear wired so they move in the same direction, ie front driver moves out, rear driver moves in. I would regard this as a dipole - I may have completely misunderstood PK's intention... On 04/11/2018 at 9:56 PM, Primare Knob said: Why would 2 drivers moving in the same acoustical direction create suckouts in a room? Maybe I misunderstood what you said (see above) If I'm correct in my understanding you're proposing a box with front and rear drivers that move "forwards and backwards" in synch, like a dipole. Based on my limited understanding of acoustics, once you're below the modal range in your room (ie in the "pressure zone") to make bass you need to increase/decrease pressure. If when you say "2 drivers moving in the same acoustical direction" you mean "moving out" at the same time, then that increases pressure in the room. One driver moving out and 1 driver moving in makes no net change to room pressure (same as a dipole). I've not experimented with dipole subs, but I struggle to see how they work lower than the lowest mode if they don't change net pressure in the room...could easily be one of those "well dipole subs can create any frequency in 4 pi space, so why does a room change anything?" sort of discussions... cheers Mike
Primare Knob Posted November 6, 2018 Author Posted November 6, 2018 Maybe I misunderstood what you said (see above) If I'm correct in my understanding you're proposing a box with front and rear drivers that move "forwards and backwards" in synch, like a dipole. Based on my limited understanding of acoustics, once you're below the modal range in your room (ie in the "pressure zone") to make bass you need to increase/decrease pressure. If when you say "2 drivers moving in the same acoustical direction" you mean "moving out" at the same time, then that increases pressure in the room. One driver moving out and 1 driver moving in makes no net change to room pressure (same as a dipole). I've not experimented with dipole subs, but I struggle to see how they work lower than the lowest mode if they don't change net pressure in the room...could easily be one of those "well dipole subs can create any frequency in 4 pi space, so why does a room change anything?" sort of discussions... cheers Mike I believe you are on the correct for most of it, but the difference is that the 2 drivers are acousticly in phase with each other, while with a dipole they are out of phase by 180 degree.By accousticly, I mean the drivers follow the same pressure and depressure patern.I had to do some reading on this myself to figure out where the differences are, and then I read about this on wiki about dipole figure 8 lobing"This can be useful in reducing the stimulation of resonant room modes at low frequencies "I assume that this does apply to the SPL output, but can it also be usefully with controlling reverberation energy?I have a nearly flat SPL response, but still heaps of reverberation energy that I can't get rid off. (I have to update my other thread on this)
almikel Posted November 7, 2018 Posted November 7, 2018 10 hours ago, Primare Knob said: 2 drivers are acousticly in phase with each other, while with a dipole they are out of phase by 180 degree. By accousticly, I mean the drivers follow the same pressure and depressure patern. OK - I had misunderstood. Placing a driver on the front and rear of a box where both drivers move out at the same time is 2 monopoles, which as Dave says, based on the small distances between the drivers (compared to the wavelengths being generated) will operate as a single monopole. You won't get the figure 8 cancellation at the baffle edges you get with a dipole. On 05/11/2018 at 9:31 AM, davewantsmoore said: The dipole will excite room modes with a different (but not necessarily better or worse) strength to a monopole, depending on it's placement As Dave says, dipoles excite room modes differently because of the figure 8 pattern. 11 hours ago, Primare Knob said: I had to do some reading on this myself to figure out where the differences are, and then I read about this on wiki about dipole figure 8 lobing "This can be useful in reducing the stimulation of resonant room modes at low frequencies " I assume that this does apply to the SPL output, but can it also be usefully with controlling reverberation energy? If the sub doesn't excite a particular mode - whatever type of sub - then you won't have reverberant energy in the room from that mode from that sub (other subs may still excite that mode). Toole had some good papers on this - by deliberately placing a sub in a null for a particular mode, the sub won't excite that mode. 11 hours ago, Primare Knob said: I have a nearly flat SPL response, but still heaps of reverberation energy that I can't get rid off. This will be room related - and the more rigid the room, the bigger the issue. When you say "nearly flat", try lopping off remaining peaks with EQ - this should also reduce reverberation times for those peaks. Once you've done all you can with sub/s position and EQ, then treatment is the only thing that can reduce the reverberation times - but you need to target the treatment on the problem areas - a different discussion. On 05/11/2018 at 9:48 AM, davewantsmoore said: what is going to matter much much much more than what enclosure your build and what driver you use (within sensible reason) is where you place the subwoofer and how it excites the room. More than one subwoofer may excite the room a lot better. As Dave says, the "type" of sub will have a very small impact on the result compared to position/EQ/using multiple subs On 05/11/2018 at 9:48 AM, davewantsmoore said: Go with a sealed box. Pick your "acceptable" box size ..... you know your output requirement ..... this will tell you which driver(s) you need. Build the box exactly as documented. I agree... and keep it as simple as possible - I would recommend sealed box monopoles with 1 driver per box. You have relatively modest SPL requirements. 2 subs with the Dayton RSS390HO-4 driver should be ample. Go with as large a box as you can get away with to reduce the EQ you'll need to push the driver to 20Hz. cheers Mike
almikel Posted November 7, 2018 Posted November 7, 2018 12 hours ago, Primare Knob said: I have to update my other thread on this which thread? the VPR thread?
davewantsmoore Posted November 8, 2018 Posted November 8, 2018 On 07/11/2018 at 8:33 AM, Primare Knob said: I had to do some reading on this myself to figure out where the differences are, and then I read about this on wiki about dipole figure 8 lobing "This can be useful in reducing the stimulation of resonant room modes at low frequencies " Somewhat. It's often repeated, but mostly overstated.... A dipole will show different strengths of mode exciting .... but a blanket, "use dipole cos less room modes" is unwarranted. On 07/11/2018 at 12:13 AM, almikel said: I've not experimented with dipole subs, but I struggle to see how they work lower than the lowest mode if they don't change net pressure in the room...could easily be one of those "well dipole subs can create any frequency in 4 pi space, so why does a room change anything?" sort of discussions... Yes, sort of..... In theory, the monopole SPL will increase below the lowest room mode, and the dipole SPL will be ~ the same as in free space. Theory for these things can help explain what you saw happen ..... but sometimes isn't super helpful in predicting what will happen.
Primare Knob Posted November 24, 2018 Author Posted November 24, 2018 I have been playing with some software and things are starting to make a bit more sense.The Dayton RSS390HO can deliver 105dB at 20Hz at my listen position using 2 seperate subs at peak level. The RSS460HO can deliver 108dB at 20Hz which is roughly 105dB at my listen position and with 3dB reserve using 2 seperate subs. The Ultimate 15-22 can deliver 110dB which roughly translate into 107dB at listen position, or 105dB with 5dB reserve using a 2nd seperate sub.I would like to stay clear from peak output at 105dB in favour for less distortions. If using the RSS390 I would need to use 4 drivers and roughly a 100 liter box, which is going to put some demands on the amplifier. From the 3 different drivers, this one seems to have the strongest motor with 6.18 BL/100gram.The RSS460HO seems the more ideal choice. It will give me the reserve to stay clear from peak output and requires the smallest box, roughly 75 liter, but this driver seems to have the weakest motor, 4.68 BL/100gram.The Ultimax 15-22 will give me the most headroom, but also requires the biggest box 198 liter, and has a motor strength of 5.5 BL/100 gram.These numbers are aimed at a Qtc value of 0.625 as I believe after reading, to be a pretty good number for a well controlled subwoofer. If this is true I don't know.I don't know much about what a strong motor or BL value is either, only that higher seems to be better.I am still looking into amplifiers and like to look into more quieter options as well. The demands required for a dual driver subwoofer on the amp has me considering going with a single driver configuration as well.Does someone have any experience with a pro amplifier that doesn't have or need a noisy fan?
davewantsmoore Posted November 24, 2018 Posted November 24, 2018 10 hours ago, Primare Knob said: strong/weak motor Don't misinterpret this. Shooting for the "strongest" motor in isolation isn't necessarily "better". It's a trade-off. Imagine it like a trampoline. A strong motor is a really tightly sprung trampoline. Will you bounce higher on a tight trampoline, or a loose one? That depends, doesn't it
davewantsmoore Posted November 24, 2018 Posted November 24, 2018 11 hours ago, Primare Knob said: These numbers are aimed at a Qtc value of 0.625 as I believe after reading, to be a pretty good number for a well controlled subwoofer. There is so much "misunderstanding" published about this, that it's not funny. Words like "control" or "damping" invoke lots of incorrect assumptions. The best way to shortcut this is to realise that what "Q" is .... rather than being "control", or "damping" or anything like that.... is that it is "the shape of the frequency response". Example: http://images.audiojudgement.com/2016/01/Frequency-response-QTC-sealed-enclosure.jpg When the frequency response is not flat (like all of these are), there is ringing in time. The driver doesn't start/stop when the input signal says it should. ... but if you "apply EQ to the response" .... then you have a different shaped frequency response (which is a different Q) ... and the Qtc that you calculated from your box, is long gone (irrelevant). Remember "applying EQ to the response" ... could be Room gain Position of the speaker and listener in the room (eg. room modes) A port/vent or a horn A passive crossover filter An active crossover filter In short.... when people say "Qtc of X" is desirable.... They are assuming the the frequency response will be exactly what the box causes it to be. As soon as something else changes the frequency response of the driver/box combo - you have a totally different Q. 2
davewantsmoore Posted November 24, 2018 Posted November 24, 2018 11 hours ago, Primare Knob said: Does someone have any experience with a pro amplifier that doesn't have or need a noisy fan? https://www.hypex.nl/product/fusionamp-fa501/158
almikel Posted November 25, 2018 Posted November 25, 2018 (edited) 2 hours ago, davewantsmoore said: https://www.hypex.nl/product/fusionamp-fa501/158 any good quality class D amps are ideal for subs if you want avoid fans. The class D/switching architecture is inherently more efficient (than class A/B amps), so less waste heat needs to be gotten rid of. I haven't listened to the DEQX amps, but based on my experience with DEQX products, they will sound excellent. I understand they're based on Hypex modules. They're a stand-alone/separate box, rather than a "plate" amp requiring "building" in to your sub enclosure or other box. https://www.deqx.com/products/amplifiers/ cheers Mike Edited November 25, 2018 by almikel
davewantsmoore Posted November 25, 2018 Posted November 25, 2018 14 minutes ago, almikel said: I haven't listened to the DEQX amps I understand they're based on Hypex modules. Yep, they're the hypex module(s) in a box... You don't get: DSP features Unbalanced inputs Digital inputs Pass through of analogue and digital Signal detect on/off You do get: Double the price
almikel Posted November 25, 2018 Posted November 25, 2018 39 minutes ago, davewantsmoore said: Yep, they're the hypex module(s) in a box... I'm sure there are lots of other options available with the hypex modules "in a box" - I'm not in the market for new amps, so I haven't looked. 39 minutes ago, davewantsmoore said: You do get: Double the price Fair enough. In my dealings with DEQX, the pricing ended up less than the Australian $ equivalent of their advertised US pricing (by a reasonable margin). PK could contact Alan from DEQX if he's interested. 39 minutes ago, davewantsmoore said: You don't get: DSP features Unbalanced inputs Digital inputs Pass through of analogue and digital Signal detect on/off Based on your link to the Hypex plate amp and the link to the DEQX amps: DSP features would definitely by a plus that's lacking from the DEQX amps unbalanced inputs - having mucked with mixing pro and consumer gear for years I've never found this an issue (ie plugging unbalanced gear into a balanced input) The Hypex module you linked to doesn't seem to have a digital input? in an active setup I'm not sure why PK would need pass through analog for a sub? signal detect is included in the DEQX amps Yes I'm a DEQX fanboi - I'm very happy with my double DEQX setup (no DEQX amps though) - but it's their after sales service that I've been most impressed with. If PK wants an amp "in a box" then he should look at options - DEQX is one of those that is locally available and supported. Many other options are likely available. cheers Mike
davewantsmoore Posted November 25, 2018 Posted November 25, 2018 1 hour ago, almikel said: Fair enough. In my dealings with DEQX, the pricing ended up less than the Australian $ equivalent of their advertised US pricing (by a reasonable margin). Actually I miscalculated. Double is wrong. The Hypex 500w plate amp (with the features mentioned earlier) is $485 AUD .... and the DEQX 1x 500w version (in a box, but without the features) is $1345
davewantsmoore Posted November 25, 2018 Posted November 25, 2018 1 hour ago, almikel said: The Hypex module you linked to doesn't seem to have a digital input? I linked the wrong one. There's a 1x500w plate amp and a 2x250w plate amp. The 1x500 has analogue only inputs, and a high-level (speaker) input .... Like a typical subwoofer does (this plate amp is featured up for a subwoofer) The 2x250 has analogue and digital inputs. It's designed for a 2 way speaker (so drops the high-level/speaker input) .... but this 2x250 module, can be bridged into a 1x500 amp. If you didn't want the digital input, you could use the 1x500 module ... which is cheaper at $480. I am rearchitecting my system with these plate amps in my subwoofers.... using the digital inputs/outputs to "chain" them all together and optimise my cabling.... and provide a "single input" to the entire subwoofer swarm (for things like Dirac Live, etc. which only understand "one subwoofer"), while maintaining the ability to do correction individually in each subwoofer. Note: The DSP in these amplifiers is IIR only (no phase correction). I will do my phase correction (for the overall "subwoofer channel") in the source. 1 hour ago, almikel said: in an active setup I'm not sure why PK would need pass through analog for a sub? Let's say you had 3 subwoofer in the rear of the room. You just need to run one cable front room to back room. You can also do as I described above.... and connect a "chain" of individually EQed subwoofers to a "single output" of devices which only consider "one subwoofer". Hope that makes sense. 1 hour ago, almikel said: signal detect is included in the DEQX amps It didn't look like it. 12v trigger, yes. ... but what about turn on/off, on input signal detect?
Nada Posted November 25, 2018 Posted November 25, 2018 Dayton Audio 18" Reference Series HO "Running the driver in free air with sine waves indicates that it is capable of nearly twice as much stroke as the Xmax would indicate with a value of about 20 mm seeming like a good value for "useful" excursion after which the output distorts heavily." 1
davewantsmoore Posted November 25, 2018 Posted November 25, 2018 3 hours ago, Nada said: capable of nearly twice as much stroke as the Xmax would indicate That's about typical ... ie. a motor might be linear for about half it's possible travel ... but there are a lot of different ways people calculate "what is linear?"
Primare Knob Posted November 26, 2018 Author Posted November 26, 2018 (edited) Speakerboxlite SPL levels are based upon max power ratings, where the cone excursion ends up being bigger than xMax. Looking at the RSS460HO and UM15-22, WinISD sets the max SPL_LF at 20Hz at 104dB for both drivers, and this seems to be based upon the xMax value. Only when looking in the graph for cone excursion on both drivers, the drawn graph doesn’t even come close to xMax. Am I doing something wrong? In WinISD when I Iower the Pe value of the driver until the max SPL value starts to drop below 104dB(xMax limit) I end up with a value of 600W for the RSS490HO and 350W for the UM 15-22. Does this sound alright? I have been working with the idea for the amplifier that I will need RMS max and Peak max output, looking at 800-1000W RMS amps and double that for Peak output, but it looks that I might not need it for my max 105dB target. That 104dB max is still not at listen position and I would need 3dB more or ideally 5dB. At least it has become clear that I can stay clear from any max output needed from driver or amp (depending on the amps specs). In WinISD giving the box a bigger volume doesn’t increase the LF output as it does with SpeakerBoxLite due to the xMax limit. I can decrease the Box volume down to 40L for the RSS460HO before it has an impact on the 104dB maxSPL output at 20Hz, or anything below 50Hz. This seems consistent with Speakerboxlite, where the same 40L keeps the xMax within limits. With the UM15-22 it comes down to a minimum box volume of 50L, but that does influence the shape of the curve with a hump. Do we need to stay within xMax, and how much do we want to stay within xMax? It has become clear now that Q doesn’t matter. I wasn’t thinking with my head straight and didn’t consider the SPL graph to be a theoretical in room output response which I do want to EQ. Edited November 26, 2018 by Primare Knob
Primare Knob Posted November 26, 2018 Author Posted November 26, 2018 23 hours ago, Nada said: Dayton Audio 18" Reference Series HO "Running the driver in free air with sine waves indicates that it is capable of nearly twice as much stroke as the Xmax would indicate with a value of about 20 mm seeming like a good value for "useful" excursion after which the output distorts heavily." I could use this as a design to build myself, as I think shipping will be expensive. I was thinking of using 32mm plywood for the build. Parts Express uses a 4 cu ft box while Dayton recommends a 3 cu ft. It doesn't seem to make a big difference except for cone excursion.
davewantsmoore Posted November 26, 2018 Posted November 26, 2018 4 hours ago, Primare Knob said: Speakerboxlite SPL levels are based upon max power ratings, where the cone excursion ends up being bigger than xMax. Looking at the RSS460HO and UM15-22, WinISD sets the max SPL_LF at 20Hz at 104dB for both drivers, and this seems to be based upon the xMax value. Only when looking in the graph for cone excursion on both drivers, the drawn graph doesn’t even come close to xMax. Am I doing something wrong? The cone excursion chart responds to the "input power" on the "signal tab". Yes, the max SPL is based on the Pe or Xmax at 20Hz You can see that if you dial in whatever power it takes to push the driver to ~104dB@20Hz (~680w in the default sealed box) .... you will see that it is right on Xmax at 20Hz. 4 hours ago, Primare Knob said: In WinISD when I Iower the Pe value of the driver until the max SPL value starts to drop below 104dB(xMax limit) I end up with a value of 600W for the RSS490HO and 350W for the UM 15-22. Does this sound alright? Yes, about right. However, don't change Pe. Pe is the "maximum power" the driver can cope with. If you want to see the SPL for certain power.... change the input power on the signal tab ... and look at the "SPL" chart. 4 hours ago, Primare Knob said: I have been working with the idea for the amplifier that I will need RMS max and Peak max output, looking at 800-1000W RMS amps and double that for Peak output In that case you may nee to be careful about how your amp is rated for peak power. How much distortion does the amp make at "peak power?". Unless the amp manufacturer has already been conservative, I would want to keep 3dB in reserve .... ie. double the number of watts than you will use.... but again, this depends lots on what the manufacturer actually mean when they well you the amp can put out "800w peak power" or whatever. 4 hours ago, Primare Knob said: Do we need to stay within xMax, and how much do we want to stay within xMax? This depends on how the manufacturer has determined xmax.... and it depends on how far the driver can actually travel before it hits it's mechanical limit (typically called xmech, xlim, or xdamage... or often not specified) You can push the driver beyond xmax towards xmech .... but you need to measure the distortion of the driver under these conditions to see if were too high. So the short answer is No.... but you need to answer the question, much farther can you go before there is too much distortion, and before the driver breaks. .... But, depending on the driver and box, it might not be problem. If you sim 900w into this driver (which you will probably need a "2kw amplifier" to do realistically without the amp distorting) .... the you get about 16mm distortion at 10Hz. This will be fine. Also, if you factor in the room gain (that winISD isn't) ... and another woofer .... then you're not going to be this close to the edge, to hit your 105dB target. So, all in all - it's a safe design. 2x of these, in room, are going hit 105dB @ 20Hz (with a 12dB/octave roll off below) ... within the power and excursion limits.
Primare Knob Posted November 26, 2018 Author Posted November 26, 2018 I hadn't found out yet about the signal input tab.As I understand you can control xMax curve or "efficiency" by changing the box volume, is this what the size of the box is all about?The hypex amps are rated in RMS but it doesn't state anything about the peak power output. Is it save to assume that they have a 3dB or peak reserve?The other thing I haven't read into yet is, do I need to protect the amp or woofer from very low frequencies?Which woofer would you recommend? Is the RSS460HO good to use?
Recommended Posts