Hi All, been offline for quite a while, since i finished my major build. Despite it being a year long learning experience and trying to use best-practise on every aspect (within the limits of my requirements for a compact system) honestly ive never been totally happy with the sound. the subwoofers particularly have never really satisfied me, and the whole system seems to be missing something. The subwoofers (compact things with slot ports) do crank out bass, but its a bit resonant and boomy, and overall the system is missing "slam!"
i remember at the time, i had a laugh when somebody here described my chosen subwoofer drivers (https://www.daytonaudio.com/product/120/rss265ho-4-10-reference-ho-subwoofer-4-ohm) as "mud-shovels" and i assume the criticism was spot-on. i chose them since a) i got them for an amazing price and b) they allowed me to build the subs small (also they did have great reviews so im not a complete idiot)
so anyway, im evaluating options. specifically, im wondering if some other enclosure type might allow these sub drivers to sound better.. ideally also reaching higher to improve the punchiness of the sound. (they claim to go up to 600 hertz, id be happy with kick drum range at 2-300hz.) at the moment they cross over to my dual driver alpair fullrange cabinets (also ported enclosures) at around 85 hz.
Id not go higher with the current cabinets as first, they are not positioned well for stereo imaging if they go higher, second, the drivers are down-firing and third, with a 210 gram cone, they have a habit of jumping off the floor despite weighing close to 20kg.
i was playing with the idea of some kind of transmission line (pvc pipe?) or tapped horns, placed under or behind the fullranges, with the drivers forward firing.
i do vaguely remember however that these drivers were not well suited for tapped horns.
itll break my heart to replace the very pretty (imho) translam cabinets i spent months designing and building, probably with something 3x bigger and ugly. but if it doesnt sound good, whats the point?
any suggestions most appreciated.
i remember at the time, i had a laugh when somebody here described my chosen subwoofer drivers (https://www.daytonaudio.com/product/120/rss265ho-4-10-reference-ho-subwoofer-4-ohm) as "mud-shovels" and i assume the criticism was spot-on. i chose them since a) i got them for an amazing price and b) they allowed me to build the subs small (also they did have great reviews so im not a complete idiot)
so anyway, im evaluating options. specifically, im wondering if some other enclosure type might allow these sub drivers to sound better.. ideally also reaching higher to improve the punchiness of the sound. (they claim to go up to 600 hertz, id be happy with kick drum range at 2-300hz.) at the moment they cross over to my dual driver alpair fullrange cabinets (also ported enclosures) at around 85 hz.
Id not go higher with the current cabinets as first, they are not positioned well for stereo imaging if they go higher, second, the drivers are down-firing and third, with a 210 gram cone, they have a habit of jumping off the floor despite weighing close to 20kg.
i was playing with the idea of some kind of transmission line (pvc pipe?) or tapped horns, placed under or behind the fullranges, with the drivers forward firing.
i do vaguely remember however that these drivers were not well suited for tapped horns.
itll break my heart to replace the very pretty (imho) translam cabinets i spent months designing and building, probably with something 3x bigger and ugly. but if it doesnt sound good, whats the point?
any suggestions most appreciated.
Yes, just try them sealed. It's enough to stuff the ports with clothes. You may need some additional bass equalization, but I guess they are actively driven anyhow, so a linkwitz transform is not too difficult.
Maybe post some data and pictures of your build, so one can see what you dislike.
This subwoofer driver is 100% OK. Forget the stupid "mud shovel" comment. Any driver can sound
disapointing in the wrong housing.
A possible fix is closing the port and DSP' the sub. A cabinet too small for a vent may be right closed.
Next, full ranges may not be able to deliver the slam you expect. A dynamic bass impulse starts in the tweeter...
This subwoofer driver is 100% OK. Forget the stupid "mud shovel" comment. Any driver can sound
disapointing in the wrong housing.
A possible fix is closing the port and DSP' the sub. A cabinet too small for a vent may be right closed.
Next, full ranges may not be able to deliver the slam you expect. A dynamic bass impulse starts in the tweeter...
Hi!
This speaker can produce very good results.
Could you share the details of your current enclosure so we can understand what you have now?
Specially the volume and tuning frequency you've chosen.
How much power do you apply to these speakers? So we can check port size, air velocity, eq possibilities etc.
From a quick simulation I've done here, with a 40-liter enclosure you would have a very nice FR down flat to 24Hz @-3dB (RED plot).
Even with a tiny small 20-liter enclosure, FR would go flat down to 31Hz @-3dB (BLACK plot).
I would definitely put this subwoofer forward firing in the same enclosure of the full range, making a true full range single loudspeaker.
Much better phase alignment around the crossover region. I like the sound coming from a single baffle.
A layman's opinion. There's probably nothing wrong with your subs. The problem is more likely your deployment and expectations. A subwoofer grunts, rumbles and shakes. It does not produce anything tuneful. A 10" sub typically works best when focussed between 30 & 65Hz. Just because the driver can reproduce 600hz doesn't mean it's any good at it. Crossover frequencies above 80hz produce directional issues.
Any texture in the bass; tightness, punchiness, attack etc. is revealed in the overtones and not the fundamental frequencies. It is the woofer and not the subwoofer that largely governs tone and texture.
The reason we have multiway systems is because different drivers are better at different frequencies. For example: my Sony mains (5" bass) sound nice, relieve them of the responsibility of sub 80hz signals and they come into the their element, the woofers cease to flap around trying to reproduce frequencies they are uncomfortable with.
In short: the experience of bass is produced subwoofers. The sound of bass is shaped at higher frequencies.
Any texture in the bass; tightness, punchiness, attack etc. is revealed in the overtones and not the fundamental frequencies. It is the woofer and not the subwoofer that largely governs tone and texture.
The reason we have multiway systems is because different drivers are better at different frequencies. For example: my Sony mains (5" bass) sound nice, relieve them of the responsibility of sub 80hz signals and they come into the their element, the woofers cease to flap around trying to reproduce frequencies they are uncomfortable with.
In short: the experience of bass is produced subwoofers. The sound of bass is shaped at higher frequencies.
Question: have you done any frequency response measurements?
The lack of "punch" may be an acoustic issue. My 8"+1" 2-way main speakers measured flat down to below 20Hz in-room, but there was some ugliness in the 80-160Hz octave due to room interactions. The result was that there was plenty of deep bass, but the upper-bass "slam" was missing.
After trying measurements in a few different positions, I determined that the problem was reflections in the vertical plane.
So, I added a second woofer near floor-level, made it a 2.5-way, re-did the system EQ to account for the extra output below about 300Hz (ie, it's nominally flat again), and now the bass is as good as those drivers can produce.
Given that subwoofers are often asked to reproduce 2-3 octaves of information, I must disagree with Surtsey's assetion that "It does not produce anything tuneful."
Even a bandwidth of just one octave should allow plenty of discernable notes in the subwoofer range. I don't know what Surtsey's reference system is, though, so it's possible his experience differs to mine.
Chris
The lack of "punch" may be an acoustic issue. My 8"+1" 2-way main speakers measured flat down to below 20Hz in-room, but there was some ugliness in the 80-160Hz octave due to room interactions. The result was that there was plenty of deep bass, but the upper-bass "slam" was missing.
After trying measurements in a few different positions, I determined that the problem was reflections in the vertical plane.
So, I added a second woofer near floor-level, made it a 2.5-way, re-did the system EQ to account for the extra output below about 300Hz (ie, it's nominally flat again), and now the bass is as good as those drivers can produce.
Given that subwoofers are often asked to reproduce 2-3 octaves of information, I must disagree with Surtsey's assetion that "It does not produce anything tuneful."
Even a bandwidth of just one octave should allow plenty of discernable notes in the subwoofer range. I don't know what Surtsey's reference system is, though, so it's possible his experience differs to mine.
Chris
From memory, you do PA stuff where different rules apply.
My simple test: cross a sub @ 50Hz and listen to it independently. As an experienced listener I cannot tell if the sound originates from: an electric bass, double bass, 808, or nuclear warhead.
It is the overtones rather than the fundamentals that provide the different sound textures. It's the reason 50hz on a bass guitar, keyboard, and 808 all sound different.
An interesting sidebar: I was raised on Funk / Jazz Funk. In this genre the bass is often the lead - it needs to sound right. Ask a customer to hum "Good Times" - you'll get the bassline. "Bat out of Hell" - not so much.
Try this for dynamics of bass.
thanks for all your replies, ill dig out the relevant info regarding the current setup and post it here. might be a little while as i have some urgent work on.
off the top of my head this is the original thread i started at the beginning of the project. which was just supposed to be a single 8 inch sub to augment an exisiting system, and grew into a dual 10 inch sub, twin driver fullrange speakers and a 6 channel class D amp with built in Minidsp. - i posted some photos on the last page of the final result.
ill see if i can find a thread with response curves etc.. there were a lot of threads.
ill see if i can find a thread with response curves etc.. there were a lot of threads.
This is quite clearly a thread about home HiFi. It's possible for me to differentiate between that and professional sound reinforcement, and I'd ask that you avoid dismissing my posts so quickly in the future.
Your previous post:
Is subtly different.
A tune requires notes, and a home HiFi subwoofer should be able to play from A0 to G2 as a minimum:
ie, a subwoofer can play a tune.
So, I stand by my previous post.:
The tonality of each note is, of course, differentiated by the harmonics, which may or may not fall within the subwoofer's bandwidth.
Chris
well further to this discussion, i was playing in hornresp, looking at a potential TL configuration for these drivers. just playing, you know.
im no expert in hornresp, but i got what seemed to be a fairly flat response from about 25 hz up to 150 or so. two drivers in series in an offset position in a 380cm line.
however changing the pmax setting in the wizard (which i assume is amplifier power), the drivers hit xmax on only 37 watts, which seems.. wrong. ive probably messed up some parameter somewhere, or its a terrible idea!
anyone fancies taking a look for fun, id be interested to see if it might be worth persuing.
To be honest ive got the building bug again, and even if theres nothing wrong with the current boxes, id like to hear these drivers in another config.
im no expert in hornresp, but i got what seemed to be a fairly flat response from about 25 hz up to 150 or so. two drivers in series in an offset position in a 380cm line.
however changing the pmax setting in the wizard (which i assume is amplifier power), the drivers hit xmax on only 37 watts, which seems.. wrong. ive probably messed up some parameter somewhere, or its a terrible idea!
anyone fancies taking a look for fun, id be interested to see if it might be worth persuing.
To be honest ive got the building bug again, and even if theres nothing wrong with the current boxes, id like to hear these drivers in another config.
You have build some really nice cabinets, but the vent is much too long, bend and the volume of 18 liter too small to be an optimal construction Maybe find a woofer that plays in such a small box. Making the vents shorter should be no problem. I would look for a really good 8" sub. The cutout can be modified with some kind of adapter ring you simply screw in.
A good idea is to ask and discuss the volume, driver and its tune, so you don't make such a mistake again. There is another problem with Dayton Audio drivers. They are produced for a long time and manufacturers seem to change material like magnets or tolerances quite often when looking for cheaper production. Which may result in very different data than the data sheet predicts. Dayton/ Parts Experss doesn't care for this problem as long as they still look the same from the outside. If you pick a driver it is a good idea to do your own TSP measurements and return it when it is far off and will mess up your simulations.
Simulations are 100% spot on, but only if feed the right parameter. The so called "down fire" position (what a ridiculous phrase) is not the best idea with heavy cones. Some may tollerate it, others sag over time. If a vent gets too long, 40cm seems to be a good measure, consider a passive radiator. It has huge advantages in some (many) cases.
About your satellites there may be very different opinions. Imo for dynamic program with hard hits it may not be the best solution to say it polite.
I would consider to "fix" this problem with an excellent tweeter, instead of the second driver going MT or in the middle of them, a MTM. That should produce any rim shot life like. You can blame a lot on the room, but not everything as some may do.
A good idea is to ask and discuss the volume, driver and its tune, so you don't make such a mistake again. There is another problem with Dayton Audio drivers. They are produced for a long time and manufacturers seem to change material like magnets or tolerances quite often when looking for cheaper production. Which may result in very different data than the data sheet predicts. Dayton/ Parts Experss doesn't care for this problem as long as they still look the same from the outside. If you pick a driver it is a good idea to do your own TSP measurements and return it when it is far off and will mess up your simulations.
Simulations are 100% spot on, but only if feed the right parameter. The so called "down fire" position (what a ridiculous phrase) is not the best idea with heavy cones. Some may tollerate it, others sag over time. If a vent gets too long, 40cm seems to be a good measure, consider a passive radiator. It has huge advantages in some (many) cases.
About your satellites there may be very different opinions. Imo for dynamic program with hard hits it may not be the best solution to say it polite.
I would consider to "fix" this problem with an excellent tweeter, instead of the second driver going MT or in the middle of them, a MTM. That should produce any rim shot life like. You can blame a lot on the room, but not everything as some may do.
Im surprised to hear you think the vents are way too long and the box too small. the driver is specifically designed for small enclosures, and the whole project was simulated repeatedly over months using WinISD, and discussed extensively with the help of many far more expert people than me on these forums. I cant find the old project files, they will be on one of my archive drives somewhere. having said all that, as ive noted the result isnt the best so maybe you are right and the sims were wrong.
I know what the simulations say, but there is also some other physics involved. First, did you measure the TSP of your driver? They may not be exactly what you gave the simulation to chew on. There is some experience you get over the years while building speakers. Such a long vent bend around in the cabinet may be more of a transmission line than the vented construction the simulation expects. My advice would be to measure the TSP yourself, REW does most for you. The bare driver has to be in free air. If you don't like that, you seem to be good in wood working. You sure can do a quick test cabinet. Maybe give this driver 35 liter net volume and a matching vent. Some straight round tube will do. This should work much better. 18 liter with a 10" driver is on the very low side for what you expect.
One more alternative to measuring TSP by yourself. Read about ground plane measurements and perform some with the sub. That should show you what your sub really does.
One more alternative to measuring TSP by yourself. Read about ground plane measurements and perform some with the sub. That should show you what your sub really does.
As far as diaphragm displacement is concerned, assuming linear operation, your transmission line loudspeaker design without any filtering can comfortably accept Eg = 30 volts, equivalent to 112.50 watts into 8 ohms or 128.57 watts into two 3.5 ohm drivers connected in series.
There is nothing wrong in putting this driver in a transmission line, just volume will be much larger. Also, if the real Qts of the driver is much higher than written in the data sheet (which is what I fear), it should tollerate it better. A transmission line should give a very different kind of bass, if you can fit it into your room.
space i have plenty of. . its wife approval that is the more likely constraint. it was the reasoning behind the tiny subs in the first place.
I wonder if the TL sound is anything like the sound of a tapped horn? Years ago I built 4 of those using one of volvotreter's designs (6.5 inch tangband drivers tuned to 30 hz) and with 4 of them in a room the bass was amaaazing. Unfortunately that was a loong time ago, and i now live in another country so who knows where those are, i left them with my flatmate in london when i left. id have liked to try these drivers in a similar box, but from what ive seen they dont work very well in a tapped horn.
I wonder if the TL sound is anything like the sound of a tapped horn? Years ago I built 4 of those using one of volvotreter's designs (6.5 inch tangband drivers tuned to 30 hz) and with 4 of them in a room the bass was amaaazing. Unfortunately that was a loong time ago, and i now live in another country so who knows where those are, i left them with my flatmate in london when i left. id have liked to try these drivers in a similar box, but from what ive seen they dont work very well in a tapped horn.
ahh, so thats how it works! i was adjusting the "pmax" setting at the bottom, with the xmax set.. the graph went "thick red line" (i assume clipping) when i set the pmax to 37 or so..
When the Pmax slider is enabled the amplifier in effect becomes a constant power source (unless Xmax displacement limited), rather than a constant voltage source.
Pmax = 37 watts (constant power source):
Eg =30 volts (constant voltage source):