Yes, this is a limit I set. Of course, I would like my speaker to be able to play 96 dB, but it's not a requirement for me as the room is untreated and only has a maximum of 12-14 sqm. So I'll never play that loud sitting at 2.5 meters...
I think the 2-way ported design (and components that I chose) are pretty solid. I put it aside. Continue to think about the 2.5-way sealed option.
Hello,
My preference is a sealed 2-way pair of speakers with a shared subwoofer. AKA 2.1
I use a 2.1 system: 6 1/2 inch Purifi mid-bass + TW29B-B tweeters on my bench / desk in a ~10sqm lab space. The 2-way speakers without the sub have a F3 of ~80Hz which is fine for most things. For movies with bass effects turn on the sub then you can feel the rumble.
I do not ask the Purifi drivers to deliver low bass.
My preference is a sealed 2-way pair of speakers with a shared subwoofer. AKA 2.1
I use a 2.1 system: 6 1/2 inch Purifi mid-bass + TW29B-B tweeters on my bench / desk in a ~10sqm lab space. The 2-way speakers without the sub have a F3 of ~80Hz which is fine for most things. For movies with bass effects turn on the sub then you can feel the rumble.
I do not ask the Purifi drivers to deliver low bass.
Are you using active crossovers? If not , very low crossover points become difficult and impractical if passive filters are used. There are a lot of design considerations here like diffraction step correction. A 2.5 way can be tricky, it's easy to end up with too much bass output. Generally speaking, a sealed box will ( in theory) give more clarity in the midrange than letting it reproduce low bass.
FR graph looks great! (So does the THD) 👍🏻
Yes it’s a 3 channel hypex. I suspect without DSP it’s not easy. I don’t know where the addition of second woofer will take F3 or overall bass below 100-120 Hz, but I’m sure, with 4 x 12 inch sealed woofer playing in this room will be bombastic (pun intended…). I’ll have the deal down a lot off bass below 50-120 I assume…
Okay, you will have a lot of control over slope rate, XP points and overall freq response, so it really comes down to your 1st question which was if a sealed enclosure would be better for a clearer midrange. So if you have 3 channels, why not treat your " upper " woofers like a proper midrange in a sealed cavity and crossover at 250 or so. Am I correct in assuming you have 3 channels to play with?
if we make the assumption that a lower f3 in a vented system will degrade the midrange sound quality, ( and it may, but.... at low volumes is it audible?) why not take it up a notch with a higher xo point and treat the system as a proper 3 way . I still think that the horn should be crossed over a tad higher but I'm generalizing and don't know the facts
if we make the assumption that a lower f3 in a vented system will degrade the midrange sound quality, ( and it may, but.... at low volumes is it audible?) why not take it up a notch with a higher xo point and treat the system as a proper 3 way . I still think that the horn should be crossed over a tad higher but I'm generalizing and don't know the facts
OP can use passive crossovers. They are simple and effective.
https://www.sound-au.com/articles/pllxo.htm
https://www.parts-express.com/FMOD-Crossover-Pair-50-Hz-Low-Pass-266-250?quantity=1
Everyone has DSP but me🙁
https://www.sound-au.com/articles/pllxo.htm
https://www.parts-express.com/FMOD-Crossover-Pair-50-Hz-Low-Pass-266-250?quantity=1
Everyone has DSP but me🙁
@gdillon there are two links above. One with instructions on how to make your own XO, perhaps with the most expensive high quality capacitors on the planet and another to where you can buy a quick simple solution. Here is another link with simple instructions for the DIY crowd: https://t-linespeakers.org/tech/filters/passiveHLxo.html This short reference should give you enough time to go back and trace the signal path through all of your audio devices and check the provenance of the capacitors.
Well thank you! I tend to take a minimal approach to the audio signal path and use a pass TVC as a preamp, most inline filters are pretty generic and only offer a 6dB solution and you need to know your input impedance to calculate the xo freq. Why do this if you have a DSP? I am also not a fan of any DSP, again anything you put in the signal path changes the sound quality and I have learned that 1s and Os are not simple 1s and Os, input boards , power regulation, and circuitry play a huge role in digital sound quality and for me less is more. But I digress.
You're right—and for my use case, maybe not. My first question was exactly what you wrote: I could build a 3-way instead of a 2-way, using the same horn (which pairs well with a 12-inch woofer around 800–900 Hz). So, why not use a dedicated mid-woofer for 100–800 Hz and a subwoofer for below 100 Hz? This is a valid approach, but the issue is that with 12-inch woofers, the cabinet height would be at least 2 × 32 cm + 25 cm + some padding, totaling around 90–100 cm. Unfortunately, a 100 cm tower with a minimum 36 cm width is too large for my living room.
This brings me to the second option: since a ported design would cover the entire 30–800 Hz range with one woofer, why not use two woofers in a 2.5-way sealed configuration? If the subwoofer is crossed over around 100 Hz, I could place it on a different axis, such as the sides or back. This allows me to keep the speaker height shorter while slightly increasing the depth. However, this approach may not deliver the midrange clarity I’m aiming for around 500–800 Hz. (Up to 500 Hz, I have high confidence in Faital, but the 500–800 Hz region could benefit from a separate mid-woofer.) That said, a 2.5-way sealed design offers several advantages: a faster ADSR envelope, multiple bass sources, no port noise, and a -12 dB/octave roll-off. I see these as significant pros.
I chose a horn from Audiohorn.net and simply following his advice about directivity. I'll measure and see the final crossover point myself, but I don't expect it to pass 800-900 Hz.
I definitely don't want to have group delay or port noise... It's either 2-way ported with the crossover around 800 Hz or 2.5-way sealed. Thanks 🙂
I’ve used Hypex FA series amps with DSP previously. I’ve also measured and applied room EQ in several listening rooms and studios. When applied correctly, I believe DSP has less impact on sound quality than many other factors. But that's me.
I'm getting the big picture, as mentioned, a 2.5 ways can be tricky to make , you can end up with too much output in low bass but if you are tri amping, then no worries . It's 8am in Los Angeles while I write this and my brain is not yet fully functional but if you are making a system that is purely dependant on DSP, simple use a smaller enclosure that works for your room, you don't have to follow any recommend bass " alignment" you could just make a smaller enclosure and EQ the system to have the desired F3 . Bass alignments are just suggestions to have a flat frequency response, there is no law or magic or better sound quality in a suggested alignment. As long as you are not over driving your woofers past their xmax, all is well, how will this sound..... Not sure but all those home Bluetooth systems have gobs of EQ and some sound amazing. Just a thought
And regarding group delay, Uggg, it is actually the rate of phase change and is always a part of a LF system and the higher the order slope rate, the more GD. Is this audible? I don't know . I just built a dipole system and it's the best bass I have ever obtained in my listening room and has the lowest GD but also a bunch of other things going on . People like the punch and sound quality of a sealed box, but the extension of a ported .
Fun fact :
if you calculate the GD at say 60Hz in a ported system, the delay is equivalent to having your woofers something like 30 feet physically behind your your high frequency drivers, I would intuitively say that this probably doesn't sound good. I'm not fully up-to-date with what mini DSP can do these days but can't you create some FIR filters to remove the delay at low frequencies and do a/b testing? That would be really interesting, I would also like some people to do the same thing at a typical tweeter crossover point and do a/b testing with and without any delay in the system to see if delay ie group delay is actually audible I don't think it is at higher frequencies but at low frequencies that is possible, it's pretty large and I digress.
Fun fact :
if you calculate the GD at say 60Hz in a ported system, the delay is equivalent to having your woofers something like 30 feet physically behind your your high frequency drivers, I would intuitively say that this probably doesn't sound good. I'm not fully up-to-date with what mini DSP can do these days but can't you create some FIR filters to remove the delay at low frequencies and do a/b testing? That would be really interesting, I would also like some people to do the same thing at a typical tweeter crossover point and do a/b testing with and without any delay in the system to see if delay ie group delay is actually audible I don't think it is at higher frequencies but at low frequencies that is possible, it's pretty large and I digress.
I never thought that delaying a subwoofer, as recommended by every surround receiver ever sold, was a good idea. I delay the mains and leave my subs alone otherwise the subwoofer can be over 360 degrees out of phase. Then I add delay to the sound to lip-sync.
Arthur, sounds like you are really into karaoke. And don't delay the mains, you coffee won't be ready in a timely manner!
So there are two concepts going here, group delay and phase delay. In HT setups, delay is added to bring the satellite speakers and subwoofers into phase at the crossover point so they sum flat or sum in a way that is pleasing to the ear. Group delay is a measurement of how fast phase is changing. In low frequency systems group delay is determined by the type of woofer alignment fourth order systems(24dB) have more group delay than second order systems(12dB) dipoles roll off at 6 dB octave and have even less. Phase change is also not linear over the frequency range, a flat group delay graph does not mean that phase isn't changing It means that the change rate is constant.
I really don't know if delay or group delay is audible at low frequencies but as mentioned if you put your woofer 30 ft behind your high frequency drivers ( a 4th order vented alignment) one could argue that that it may affect the sound quality. I would think that kind of delay would change the tonal characteristics of instruments, I don't know, It would be a fun academic test to see.
So there are two concepts going here, group delay and phase delay. In HT setups, delay is added to bring the satellite speakers and subwoofers into phase at the crossover point so they sum flat or sum in a way that is pleasing to the ear. Group delay is a measurement of how fast phase is changing. In low frequency systems group delay is determined by the type of woofer alignment fourth order systems(24dB) have more group delay than second order systems(12dB) dipoles roll off at 6 dB octave and have even less. Phase change is also not linear over the frequency range, a flat group delay graph does not mean that phase isn't changing It means that the change rate is constant.
I really don't know if delay or group delay is audible at low frequencies but as mentioned if you put your woofer 30 ft behind your high frequency drivers ( a 4th order vented alignment) one could argue that that it may affect the sound quality. I would think that kind of delay would change the tonal characteristics of instruments, I don't know, It would be a fun academic test to see.
Someone did a nice test and yes, they found that GD is audible, get out your FIR filters or go Dipole!
https://www.kvalsvoll.com/blog/2019...BX test shows that,20ms which was tested here.
https://www.kvalsvoll.com/blog/2019...BX test shows that,20ms which was tested here.