how big is your woofer, how big is your box, what's your sensitivity
- Thread starter Joe P
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cooky1257
pfm Member
Volume displacement is an inescapable property/requirement-a pretty specific mechanical requirement in this case, it hardly doesn't matter what driver (s) used.The mech limits mentioned do suggest a system limited to 96dB on peaks when wide dynamic material is used, the more compressed offerings in todays music could well mean your subs are bottoming most of the time.
I can't make Scalford but would've loved to hear them in action-proof of the pud as they say. Any patents you can point us to, any Kickstarter action I can see millions to be made in the pro/PA field?
S-Man
StrivingON
Cooky, for the third (at least) time:
The program material does not contain sufficient lf signal level for volume displacment to be a problem, with the music I listen to and at the levels I listen at (approx 100dB peaks according to my Phone, which may not be very accurate). With DVD soundtracks this is not the case and the drive units bottom out without too much provocation.
BTW, I'm only a visitor at the Wig Show this year.
Merlin - I had a chat with the designer...
He thinks boundary loading could be a very good idea - better impedance matching to the air. He did have concerns about the dry-lined walls in modern houses having insufficient rigidity to reflect the sound effectively though.
He has also studdied the Meyer X-10. It has a foible that the microphone they bolted on the front of the drive unit picks up ambient noise (e.g. when somebody slams a door) and then plays a processed version of that noise through the driver.
The program material does not contain sufficient lf signal level for volume displacment to be a problem, with the music I listen to and at the levels I listen at (approx 100dB peaks according to my Phone, which may not be very accurate). With DVD soundtracks this is not the case and the drive units bottom out without too much provocation.
BTW, I'm only a visitor at the Wig Show this year.
Merlin - I had a chat with the designer...
He thinks boundary loading could be a very good idea - better impedance matching to the air. He did have concerns about the dry-lined walls in modern houses having insufficient rigidity to reflect the sound effectively though.
He has also studdied the Meyer X-10. It has a foible that the microphone they bolted on the front of the drive unit picks up ambient noise (e.g. when somebody slams a door) and then plays a processed version of that noise through the driver.
cooky1257
pfm Member
S-Man,
Your irritation is uncalled for old chap.
I'm interested, I'm trying to get some facts rather than read repeated claims.
Had you posted "-6dB @10hz free space but output limited to 86dB"
I wouldn't have been so intrigued.
Maybe I'll just wait for Merlin to report back..
S-Man
StrivingON
That is like saying for e.g. a fast car can do 0-60 in 3 seconds, has a top speed of 190MPH and can do 50MPG. Obviously it will not do 50MPG at 190MPH!
The reality is that in normal use it does not get stretched.
cooky1257
pfm Member
More like it could do 0-60 in 3 secs but has a top speed of 50mph..
I can only guess at the performance improvements to be had should larger and better spec'd bass units be employed.
S-Man
StrivingON
More cone area with the same X-max would certainly enable higher SPL at the same (low) frequency. It would be interesting to know if the sound would be different, when used within the volume displacement limitations of the smaller drive units**.
**Somebody who I suspect would have more idea than most, thought it would sound different.
Which specifications would you suggest should be improved over the drivers I am currently using, and why?
**Somebody who I suspect would have more idea than most, thought it would sound different.
Which specifications would you suggest should be improved over the drivers I am currently using, and why?
cooky1257
pfm Member
I don't have any specs, you are saying very little other than their diameter which allowed to extrapolate the approx Sd and necessary xmax for the 10hz figure you posted.
Why am I even arsed?
Your sub bottoms with LF content from DVD at normal listening levels so perhaps this would be the first thing to address with more Sd ergo less excursion, if you are happy with your drivers then you could just use twice as many.
I've wasted too much time on this already tbh.
Why am I even arsed?
Your sub bottoms with LF content from DVD at normal listening levels so perhaps this would be the first thing to address with more Sd ergo less excursion, if you are happy with your drivers then you could just use twice as many.
I've wasted too much time on this already tbh.
cooky1257
pfm Member
TheDecameron
Unicorns fart glitter.
And it's me you need to show
How Deep Is Your Bass
How deep is your bass, How deep is your bass
I really need to learn
'Cause we're living in a world of fools
Breaking us down
When they all should let us be
How Deep Is Your Bass
How deep is your bass, How deep is your bass
I really need to learn
'Cause we're living in a world of fools
Breaking us down
When they all should let us be
S-Man
StrivingON
So finally you accept that you are speculating about the specs and that you don't know which specs are important and which are not in my application.
I's not a sub - it's a stereo pair to turn a 2-way speaker into a 3-way.
Once again you are twsting what I have posted.
My telly is not connected to my hifi at home, and I would not want to watch an entire film at the SPL we used for the DVD session AFTER we turned it down a bit to stop the bottoming.
Agreed!
merlin
Avatar changed - Town names deemed offensive.
S Man
I'm sure you have a fine pair of three ways. It's no reflection on those that Cooky and I take serious issue with the claims of your designer friend.
Just a thought though. You will not find a pair of say ATC-SCM100's bottoming on a movie soundtrack at anything approaching sane levels. What your chap seems to have done is to apply maths to solve a singular issue at the expense of others.
Your requirement seems to be low level listening. If we say that you listen at circa 80db, have a look at the levels required in the bottom octave in order to get perceived equal loudness.
Now room gain will usually help here in the domestic setting but putting your bass units where you do reduces that to an absolute minimum.
To give you an idea, corner mounted bass modules that say require 4w to produce 100db at 1m would require as much as 256 watts placed in the middle of the room along side your satellites.
Now imagine the amount your cones move when given 256w in comparison with their vibrations under just 4w.
This is admittedly taking worse case scenario but I'm sure you can get the gist of it, and why Cooky and I are rather sceptical of your chap's methods.
I'm sure you have a fine pair of three ways. It's no reflection on those that Cooky and I take serious issue with the claims of your designer friend.
Just a thought though. You will not find a pair of say ATC-SCM100's bottoming on a movie soundtrack at anything approaching sane levels. What your chap seems to have done is to apply maths to solve a singular issue at the expense of others.
Your requirement seems to be low level listening. If we say that you listen at circa 80db, have a look at the levels required in the bottom octave in order to get perceived equal loudness.
Now room gain will usually help here in the domestic setting but putting your bass units where you do reduces that to an absolute minimum.
To give you an idea, corner mounted bass modules that say require 4w to produce 100db at 1m would require as much as 256 watts placed in the middle of the room along side your satellites.
Now imagine the amount your cones move when given 256w in comparison with their vibrations under just 4w.
This is admittedly taking worse case scenario but I'm sure you can get the gist of it, and why Cooky and I are rather sceptical of your chap's methods.
S-Man
StrivingON
ATC 100s don't go much below 35Hz and the B/L curve probably flattens off quite a bit at high excursions - so I'm not surprised.
Post #114:
"The designer told me that theoretically this is not enough cone area to provide high output at 20Hz, experience has shown that is it adequate for 99.9% of music recordings "
Perfectly understandable since I cannot tell you how it's done and we are unheard of in audio circles.
As I said earlier, they are not bass monsters and I am not after stunt bass. I want excellent coherent sound where the bass performance does not mask the rest of the music. I also wanted something domestically acceptable - I live in a house, not a studio.
Post #114:
"The designer told me that theoretically this is not enough cone area to provide high output at 20Hz, experience has shown that is it adequate for 99.9% of music recordings "
Perfectly understandable since I cannot tell you how it's done and we are unheard of in audio circles.
As I said earlier, they are not bass monsters and I am not after stunt bass. I want excellent coherent sound where the bass performance does not mask the rest of the music. I also wanted something domestically acceptable - I live in a house, not a studio.
Your requirement seems to be low level listening. If we say that you listen at circa 80db, have a look at the levels required in the bottom octave in order to get perceived equal loudness.
I don't follow this.
Joe Hutch
Mate of the bloke
The blue line at 40 is almost touching the red line. The other red lines are all over the shop.
cooky1257
pfm Member
Your speakers are output limited i.e. they have zero headroom at LF, flying by the arse of your pants in regard to sub 35hz content(according to you there isn't any signal below that in modern cd's)is just plain silly.
I had the temerity to suggest you could improve this situation, pardon me. Loudspeakers approaching their xmech are non linear(see some Klippel tests...) you don't know if/when this is occurring other than a blank assumption there isn't any signal/content that low except when you bottom out your drivers-I hope they are robust.
Do a spectrum trace in Audacity and tell me there's no sub 35hz content..
merlin
Avatar changed - Town names deemed offensive.
Go on Markus. What's wrong?
Tony L
Administrator
FWIW (and entirely without science / maths) I can barely see or feel any movement at all in my two active 12" infinite baffle subs at my usual 70-75db listening level. I doubt they ever move more than a mm or so unless dealing with a Hollywood Godzilla movie or something like that. I'm currently playing Talk Talk's Spirit Of Eden and I can barely feel any cone movement at all. They do cross over very low though (about 50Hz).
S-Man
StrivingON
Third time lucky Cooky
"The designer told me that theoretically this is not enough cone area to provide high output at 20Hz, experience has shown that is it adequate for 99.9% of music recordings "