RobWells said:
Its was a joke Rob, a poor one of course though.
No way I'd have the skills to competantly machine alu or other metals. It would look something like a car wreck.
I've seen some of the work the guys do in solid state and the other amp sections. Building speakers out of wood is a piece of cake next to crafting a really good enclosure out of metal.
No way I'll be using these in another year, no matter how well they turn out. I'm always moving on, its the most enjoyable part.
If a craftsman built the finest chair he could, I'm sure he'd still build other chairs. Same goes for DIY'ers like us.
The problem is that I like my speakers same as my women. Fine that is. So finishing is a must and again its the pushing yourself to create a look that you haven't done before that's half the fun.
You don't see my turntable vision.
How about this type of design for a home subwoofer,
can you visualize this?
http://home.pacbell.net/lordpk/misc/speaker_box.jpg
How about this type of design for a home subwoofer,
can you visualize this?
http://home.pacbell.net/lordpk/misc/speaker_box.jpg
thylantyr said:
The bass driver runs up to 380hz before roll off so I'd have reservations about moving the mid and HF out of the same horizontal plane for imaging reasons.
Much easier to just toe the cabinets and and leave them 🙂
How about this type of design for a home subwoofer,
can you visualize this?
http://home.pacbell.net/lordpk/misc/speaker_box.jpg
Very Doom'esq.
Would look good in a demonic themed home theater but for anything else other than an ICE install it would look tacky. Can't fault the workmanship though even if the taste is off from my point of view
I've been playing with the newly constructed cabinets for the best part of a week now.
I'm still not happy with the W22. What I have right now is as follows:
380hz 4th order acoustic rolloff and a 55ltr enclosure tuned to 30hz via a rear firing port.
I've tried crossing upto 800hz and down to 250hz and what I have already out lined is the best is sounds from these choices.
Very disappointed. I'm not entirely sure that its anything to do with me or the drivers and I'm going to start looking at the PC XO. I feel there's something of in its execution. I've noticed that when I run a sweep the lowpass on the ATC seems to have some strange behaviour can't put my finger on it yet but I'll post back with my findings later.
I'm still not happy with the W22. What I have right now is as follows:
380hz 4th order acoustic rolloff and a 55ltr enclosure tuned to 30hz via a rear firing port.
I've tried crossing upto 800hz and down to 250hz and what I have already out lined is the best is sounds from these choices.
Very disappointed. I'm not entirely sure that its anything to do with me or the drivers and I'm going to start looking at the PC XO. I feel there's something of in its execution. I've noticed that when I run a sweep the lowpass on the ATC seems to have some strange behaviour can't put my finger on it yet but I'll post back with my findings later.
I knew it!
Take a look at this:
It seems the lowpass behaviour doesn't work like the highpass at all. Its more like a steep shelving function.
If you look at the picture it actually roll offs and then maintains amplitude after this point.
This completely explains the muddyness I was describing. Its not a case of anything wrong with cabinet design or drivers but rather the XO execution itself.
I've noticed a that this steep shelving behaviour actually changes with frequency, move the XO point up and the shelve becomes less pronounced and moving it down causes the opposite. There is a specific high accuracy LF filter in LineEQ but its limited to a filter shape that don't match the rest of the other filters.
I believe this behaviour I've noted here is actually engineered into LineEQ rather than any sort of bug.
What this means is that Waves LineEQ ISN'T suitable for use as an XO.
Take a look at this:
It seems the lowpass behaviour doesn't work like the highpass at all. Its more like a steep shelving function.
If you look at the picture it actually roll offs and then maintains amplitude after this point.
This completely explains the muddyness I was describing. Its not a case of anything wrong with cabinet design or drivers but rather the XO execution itself.
I've noticed a that this steep shelving behaviour actually changes with frequency, move the XO point up and the shelve becomes less pronounced and moving it down causes the opposite. There is a specific high accuracy LF filter in LineEQ but its limited to a filter shape that don't match the rest of the other filters.
I believe this behaviour I've noted here is actually engineered into LineEQ rather than any sort of bug.
What this means is that Waves LineEQ ISN'T suitable for use as an XO.
Try low ripple mode, located in the method dialog box in Line EQ.
FIR crossovers behave like shelving filters, the stop band can be anywhere from 40db to over 100db down depending on implementation.
Remember LinEQ is designed to be an EQ not a crossover.
A good place to see a bunch of graphs showing FIR filter behavior is any DAC datasheet, The anti-aliasing filters are all FIR and the datasheets show general FIR crossover performance.
FIR crossovers behave like shelving filters, the stop band can be anywhere from 40db to over 100db down depending on implementation.
Remember LinEQ is designed to be an EQ not a crossover.
A good place to see a bunch of graphs showing FIR filter behavior is any DAC datasheet, The anti-aliasing filters are all FIR and the datasheets show general FIR crossover performance.
You are also using very shallow slopes with FIR, Unless you are crossing above 24db/oct I would just use an IIR crossover. FIR crossovers big advantage is very steep 48db/oct-400db/oct filters, otherwise I would not mess with them.
mbutzkies said:
I've been messing with the filter mode somewhat and have come to the conclusion that accurate exhibits the least shelving nature followed by normal and then low ripple being slightly worse.
Thanks for the heads up.
What are your thoughts on this causing lowmid upper bass muddyness?
mbutzkies said:
The example shown in the screen grab above isn't indicative of my usual setup. It was merely used as an example to highlight the shelving nature.
It strange because the high pass shows no such behaviour regardless of Q. There's also the fact that the shape of the shelve is determined by frequency - its non linear.
Vil said:
Cheers Vil,
Now that I know what I'm looking at I'll run some measurements specifically targeted at identify the impact on the cross between bass and mid. Perhaps my slopes haven't been steep enough but the example above is an extreme one.
>>>>Now that I know what I'm looking at I'll run some measurements specifically targeted at identify the impact on the cross between bass and mid. Perhaps my slopes haven't been steep enough but the example above is an extreme one.
yes , thats just for testing purposes . Usually I don't use such big slopes 🙂
yes , thats just for testing purposes . Usually I don't use such big slopes 🙂
I am not saying you can't have 12db/oct slopes with FIR, I am saying why would you bother. Use IIR and get improved latency.
As far as your woofer/mid crossover
Have you tried a voxengo plugin called PHA-979. It is a phase shifter that shifts all frequencies the same phase. You might want to insert that into your plug chain and see if you can improve your crossover region. It is a different type of delay than an all pass filter, or a linear phase FIR filter.
On your previous attempt, I was wondering why you picked a woofer with 3.5mH inductance to cross with with an ATC mid. 3.5mH is subwoofer inductance. You moved to the w22 so that really should not be much of a problem anymore.
Another issue, have you used the Seas woofers in different setups with good results?. You actually might not like the SEAS sound, a lot people, mostly the paper crowd and the scan-speak crowd are critical of the "Lack of Realism" of the Seas alum/Mag woofers.
Generally, I think "Lack of Realism" is" Lack of realistic Reverb" and you might add some reverb to see if you like it. Realistic Reverb is tricky, room dependent, and genre dependent, and really depends on your tastes etc, so I really can't speak for you.
How have identified your problem area, have you limited it to the crossover area, and to the seas unit and not the ATC?
As far as your woofer/mid crossover
Have you tried a voxengo plugin called PHA-979. It is a phase shifter that shifts all frequencies the same phase. You might want to insert that into your plug chain and see if you can improve your crossover region. It is a different type of delay than an all pass filter, or a linear phase FIR filter.
On your previous attempt, I was wondering why you picked a woofer with 3.5mH inductance to cross with with an ATC mid. 3.5mH is subwoofer inductance. You moved to the w22 so that really should not be much of a problem anymore.
Another issue, have you used the Seas woofers in different setups with good results?. You actually might not like the SEAS sound, a lot people, mostly the paper crowd and the scan-speak crowd are critical of the "Lack of Realism" of the Seas alum/Mag woofers.
Generally, I think "Lack of Realism" is" Lack of realistic Reverb" and you might add some reverb to see if you like it. Realistic Reverb is tricky, room dependent, and genre dependent, and really depends on your tastes etc, so I really can't speak for you.
How have identified your problem area, have you limited it to the crossover area, and to the seas unit and not the ATC?
I know what your saying.
I've got that worked out I think.
Yes I've played around with it but it made no difference or certainly no improvements over what I'm using currently.
Its also a big CPU hog when you've got a few instances running and the latency sucks too.
I know the inductance seems somewhat high for a driver that is to be crossed over at 400hz. But I was aiming to forgo subs by using drivers capable of low frequencies.
In my revised v2 I scrapped that idea and moved onto a more capable excel that would handle a 400hz and still have an octave or so of flat output and then output the low stuff via stereo subs.
I agree its got a lack realism compared to the ATC and Scan. But I'd say I actually like the Excel sound because it feels accurate and quick. Bass is punchy without any sort of overhang, its got great tonal clarity and can handle complex bass lines with an ease that I haven't heard on most speakers I've owned or auditioned.
The only paper bass drivers I've ever liked are the Volts and I'm really scratching my head now trying to think of a reason why I never went with one in the first place? There was a reason but I think its got lost in 8 months of trying to get these things to play ball.
Its always difficult to describe the problem simply its very difficult to describe the sound. From the masses of measurements I've done everything should sound great but I'm just not feeling that, measurements vs. actual sound are two completely different things.
I'm confused as to whether I just don't like the Seas sound or if its the ATC thats naff down below or I need paper bass drivers or the crossover idiosyncracies... etc.
I've tried moving the XO point upto 800hz and there's still no decent intergration around this point between the Seas and ATC. So I very much doubt its the ATC, its more a case of driver incompatibility I think. I also think that the XO isn't actually playing a big part in the problem, running measurements reveals that the output is way way down whilst running a sweep past the XO point on each driver.
I'm half ready to pack this project in flog the drivers and start over. Maybe I've bitten off more than I can chew on this one. What really frustrates me is that I've got a quite incredible synergy between the ATC and Scan. Music really breaths and is a pleasure to listen to with these. But with most kinds of music the bass shows up the problems with the ATC and bass cross. From what I've said it sound like the Seas and ATC combo is rubbish - that's very far from the truth but its still not as perfect as I'd like.
Am I being too picky??? Actually I don't think I am.
Have you tried the troubleshooting method where you remove stuff and make it primitive to see what happens? ie,
1. Only play the Seas alone and listen to it, what do you hear?
ie, directly connect the Seas to the amplifier without any crossover, source-> amp -> Seas ... sure it's playing full range
but do you hear anything in that pass band {igore treble},
or add a coil to make a 6dB/octave crossover just to test the
sound.
2. Do a crossover frequency sweep to find the nasty sounding
crossover point, do the same for the ATC, what's the verdict?
3. What is the Seas/ATC driver spacing? Do you think it's too far or should be closer for better integration?
4. Are you driving the Seas with adequate power?
///
Finally, the best suggestion is;
Don't listen to music for a few days and go audition some expensive home audio gear, then come back and listen to yours,
I bet you will realize how much better it is and you were overreacting.
1. Only play the Seas alone and listen to it, what do you hear?
ie, directly connect the Seas to the amplifier without any crossover, source-> amp -> Seas ... sure it's playing full range
but do you hear anything in that pass band {igore treble},
or add a coil to make a 6dB/octave crossover just to test the
sound.
2. Do a crossover frequency sweep to find the nasty sounding
crossover point, do the same for the ATC, what's the verdict?
3. What is the Seas/ATC driver spacing? Do you think it's too far or should be closer for better integration?
4. Are you driving the Seas with adequate power?
///
Finally, the best suggestion is;
Don't listen to music for a few days and go audition some expensive home audio gear, then come back and listen to yours,
I bet you will realize how much better it is and you were overreacting.
I think the 4th order crossover in the critical fundamental range may be an issue. You're slowing down the rise time of the woofer a great deal. Try 1st or 2nd order crossovers for a comparison.
Have you tried the scan 8535/8545/8565 and do you prefer the volts to them? They are stiffer than normal papers, you might prefer them
I know a lot of people recommend some exotic stuff, but just remember if a driver gets damaged you are SOL. And for speakers of this price range, I like to keep my speakers for a long long time
There are about three things I would look at.
Did you overstuff your box? I think you are BR now, so you probably removed a lot of stuffing. One common mistake in closed boxes is overstuffing and that removes subjective slam from your speakers. So adjusting the stuffing is one way to change your sound even with BR.
Room interaction. Room effects generally polute 300hz and down, To clear up bass you generally have to build false walls, foam unless very very thick does nothing for bass. Do you have the same problem with your speakers outside as inside? A room that has a lot of absorbstion at high freq and very little at LF will have boomy bass. DRC is awesome but room engineering is still a must at the very high end.
Pipe mode resonances, If you picked a large tube to keep your wind speed down you can have higher order resonances, these are easy to spot, just mic your tube and do a frequency sweep, these are out of phase and can be problematic.
you stated you have tried multiple XOs and that the PC XO was the best of them and so I am assuming the problem is not in the XO. That is another ball of wax.
Have your tried a touch of reverb, There is a plugin called izotope ozone that has some pretty interesting presets to play around with.
Ozone is available in a low cost Plugin for winamp/windows media player and and full plugin for VST/DirectX.
I know a lot of people recommend some exotic stuff, but just remember if a driver gets damaged you are SOL. And for speakers of this price range, I like to keep my speakers for a long long time
There are about three things I would look at.
Did you overstuff your box? I think you are BR now, so you probably removed a lot of stuffing. One common mistake in closed boxes is overstuffing and that removes subjective slam from your speakers. So adjusting the stuffing is one way to change your sound even with BR.
Room interaction. Room effects generally polute 300hz and down, To clear up bass you generally have to build false walls, foam unless very very thick does nothing for bass. Do you have the same problem with your speakers outside as inside? A room that has a lot of absorbstion at high freq and very little at LF will have boomy bass. DRC is awesome but room engineering is still a must at the very high end.
Pipe mode resonances, If you picked a large tube to keep your wind speed down you can have higher order resonances, these are easy to spot, just mic your tube and do a frequency sweep, these are out of phase and can be problematic.
you stated you have tried multiple XOs and that the PC XO was the best of them and so I am assuming the problem is not in the XO. That is another ball of wax.
Have your tried a touch of reverb, There is a plugin called izotope ozone that has some pretty interesting presets to play around with.
Ozone is available in a low cost Plugin for winamp/windows media player and and full plugin for VST/DirectX.
Member
Joined 2003
Shin,
...just my .02, but it seems this driver combination should sound better than it does. I have noticed the W22/26 can sound "disconnected" without appropriate time offset. They seem very unforgiving in that regard.
A very subtle improvement is to flatten the breakup even when it is several octaves above xo...but that doesn't seem to be the issue in this case.
Good luck!
Paul
...just my .02, but it seems this driver combination should sound better than it does. I have noticed the W22/26 can sound "disconnected" without appropriate time offset. They seem very unforgiving in that regard.
A very subtle improvement is to flatten the breakup even when it is several octaves above xo...but that doesn't seem to be the issue in this case.
Good luck!
Paul
I'll highlight what I've done so far and the rough results:
I've isolated both the ATC and Seas and run individual frequency and impedance/phase measurements both with and without the XO in place. The only one I haven't done this with, and its because I don't fancy piping a fullrange signal through it, is the Scan ring but that driver isn't the problem.
All the plots look fine no peaks no dips aside from cone breakup on the Seas around 2.5Khz. These are two very well behaved drivers as far as measurements go.
Impedance matching has nothing to do with this since its active buy I'll mention it anyway.
I've also tested the drivers mounted and free air. I'm showing the classic double impedance spike for the Seas mounted in a ported cabinet and they correlate well with the port tuning and driver Fs. The rest of the curve is well behaved aside from cone breakup. The ATC is remarkably flat in amplitude when mounted on the baffle with a minor ripple of around 2dB at 1.2kHz which relates to the baffle since it wasn't shown in free air measurments. I also think I've got a good baffle design because the free air vs. mounted on baffle responses look very similar.
I've checked to see if the cone breakup of the Excel is causing any unwanted sound output and with the high Q notch filters in place they are completely inaudable when testing using a high SPL frequency sweep with the XO in place and just the Excel playing in isolation.
Summation around the 380hz XO point is flat, no dips, no peaks which suggested good phase matching and indeed running a gated far field acoustic center response measurement with the mic 1.5m from the tweeter axis. It shows very good phase variance to within +50/-30 degrees from 130hz upto 18khz.
I've also run gated far field response on axis for each driver to check dispertion and off axis response. The ATC was quite exeptional here and the scan working well within this 'cone' of sound with a similar radiation pattern but more focused and limited in dispertion. Since the Excel is only used upto 400hz its actual dispertion pattern is naturally large low down and doesn't roll off until you start to get to around 50degrees and even then its only at around 300hz. All in all the dispertion of the ATC and Seas mate very well at 380hz suggesting a good candidate for a crossover point.
I did note some lobbing between the ATC and Scan at around 30 degree's off the horizontal axis. This seems to steady out though and the mid range becomes slighty more prounounced at 30+ degrees as the Scan starts to roll off rapidly above around 6Khz.
Both sound and measure fine. I think its more of a tonal matching and sound signature problem than anything.
I hope not otherwise I'm in a word of hurt. That would mean building more cabinets 🙂 I can feel a nose bleed comming on just at the thought.
They measure around 23cm from acoustic center to acoustic center.
I don't think for a minute this is a problem from the vertical and horizontal dispertion measurements I made during early design. I also sit someway back from the speakers also.
At the moment it has 200w into 8ohm. I measured a 5 ohm minimum when testing but the nominal is certainly 8 or above. Its a very easy speaker to drive.
Maybe, I prefer studio monitors rather than boutique hifi non-sense. My Mackie HR626 are good reality check for me and beat the hell out of many expensive passive hifi speakers.
At the moment they don't sound a patch on the scale or realism of what I have in place now. So I might be over exposed and might just focusing and exagerating things but you know when something isn't quite right.
Cheers for the reply.
Not heard those Scans. I do however like the Volts.
The Scan bass drivers I have heard all sound somewhat muffled and heavy/slow to me. I prefer a light and nimble bass like the Seas provides but if only I could get it to play nice with the ATC.
What do you mean when you say 'if a driver get damaged'? Is there something that I'm doing that could cost me?
Hardly any fill at all, only on the walls and directly behind the driver. I've not experimented much with this apart from when measuring. I haven't done any serious listening with different amounts of fill.
Looking at the sweeps I've done in room with the RTA, I don't have any problems around 380hz, its actually quite flat. Further down the scale its ragged with a big hump at 50hz and a minor suck out at the around 90hz which I corrected with positioning. There's remarkably little postive gain on the EQ because I've tweaked to avoid that and focused on bringin the humps down in line with dips.
TBH My room only has real problems low down and even then its not enough for me to be concerned about.
******!
You know what I haven't tested the port at all. Done everything else though. That's on my to do list. Thanks!
Agreed I've been looking for problem area's and by chance found the Waves LineEQ lowpass problem by accident almost.
I'd have liked to blame my problem on that but after testing this afternoon and evening its completely inaudible and I had the volume up LOUD when testing the roll off characteristics. With Q filters at 3 and above it wasn't noticable at all.
Vils measurements also confirm this.
I'm not sure I like the idea of adding reverb. It tends to rob imaging in trade for ambience I find.
I definitely prefer to keep the sound as true to the recording as possible(my preference for studio monitors) and it seems like that is fudge to cover up other problems?
I've got a couple of reverb plugins that I can try but I'm guessing I won't like the results 😉
Not heard those Scans. I do however like the Volts.
The Scan bass drivers I have heard all sound somewhat muffled and heavy/slow to me. I prefer a light and nimble bass like the Seas provides but if only I could get it to play nice with the ATC.
What do you mean when you say 'if a driver get damaged'? Is there something that I'm doing that could cost me?
Hardly any fill at all, only on the walls and directly behind the driver. I've not experimented much with this apart from when measuring. I haven't done any serious listening with different amounts of fill.
Looking at the sweeps I've done in room with the RTA, I don't have any problems around 380hz, its actually quite flat. Further down the scale its ragged with a big hump at 50hz and a minor suck out at the around 90hz which I corrected with positioning. There's remarkably little postive gain on the EQ because I've tweaked to avoid that and focused on bringin the humps down in line with dips.
TBH My room only has real problems low down and even then its not enough for me to be concerned about.
******!
You know what I haven't tested the port at all. Done everything else though. That's on my to do list. Thanks!
Agreed I've been looking for problem area's and by chance found the Waves LineEQ lowpass problem by accident almost.
I'd have liked to blame my problem on that but after testing this afternoon and evening its completely inaudible and I had the volume up LOUD when testing the roll off characteristics. With Q filters at 3 and above it wasn't noticable at all.
Vils measurements also confirm this.
I'm not sure I like the idea of adding reverb. It tends to rob imaging in trade for ambience I find.
I definitely prefer to keep the sound as true to the recording as possible(my preference for studio monitors) and it seems like that is fudge to cover up other problems?
I've got a couple of reverb plugins that I can try but I'm guessing I won't like the results 😉
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