bass
sort of a solar powered bass shaker thingy
thanks for your thoughts allen
i still have my home audio system to listen to
then the workshops
cheers all
sort of a solar powered bass shaker thingy
thanks for your thoughts allen
i still have my home audio system to listen to
then the workshops
cheers all
test
i managed to get these graphs today
with the speakers as they are
ie no foam removeal and existing crossovers in place
the mearurements are at bass driver level and one metre from cone dust cover
from bassbox the F3 is 50 Hz so from the graph it appears that the boxes start to give response from that point onwards
i set the amp at 2.8 volts for these tests
so now i have to get to work on trying to flatten that responce curve
some more input would be appreciated
cheers speedie
i managed to get these graphs today
with the speakers as they are
ie no foam removeal and existing crossovers in place
the mearurements are at bass driver level and one metre from cone dust cover
from bassbox the F3 is 50 Hz so from the graph it appears that the boxes start to give response from that point onwards
i set the amp at 2.8 volts for these tests
so now i have to get to work on trying to flatten that responce curve
some more input would be appreciated
cheers speedie
Attachments
Hi Speedy, I'm not familiar with B weighted curves so I'm not going to comment on that, but (from the spl graph) since your crossover point is at 2000hz my first comment would be that it looks like you don't have good phase tracking around the crossover point.
It looks like you are getting some destructive interference across a reasonably broad range say from about 800Hz through to about 4000Hz. This is of course assuming that there isn't a big drop off in the woofers response from 800Hz on.
It would be interesting to see two measurements taken at the same spot, but one with the tweeter polarity reversed, from what it is now. The response from 20K down to 4K looks excellent!!
Tony.
It looks like you are getting some destructive interference across a reasonably broad range say from about 800Hz through to about 4000Hz. This is of course assuming that there isn't a big drop off in the woofers response from 800Hz on.
It would be interesting to see two measurements taken at the same spot, but one with the tweeter polarity reversed, from what it is now. The response from 20K down to 4K looks excellent!!
Tony.
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testing
thanks allen tony and salas
like all things new i am getting to slowerly understand these new software packages
what with WT3 then the microphone gig it is going to be a slow process
then once these are understood it is going to be more adapting to jeff bagbys program passive crossover designer
question do you think that placing a BSC circuit in will bring down the Db of the tweeter as it is somewhat higher than the lower range
there is no impedance compensation on the woofer at present so would this be a good idea to place one on that driver?
tony i will try the polarity swap on the tweeter and see what happens
at present it is wired out of phase with the woofer this i followed from the xover pro software plus most other information suggest + to - for that filter
others have stated that the foam could be eating up my bass signal?
now that these graphs are showing response, what do they represent in the lower end
is the Db level down due to this?
cheers speedie
thanks allen tony and salas
like all things new i am getting to slowerly understand these new software packages
what with WT3 then the microphone gig it is going to be a slow process
then once these are understood it is going to be more adapting to jeff bagbys program passive crossover designer
question do you think that placing a BSC circuit in will bring down the Db of the tweeter as it is somewhat higher than the lower range
there is no impedance compensation on the woofer at present so would this be a good idea to place one on that driver?
tony i will try the polarity swap on the tweeter and see what happens
at present it is wired out of phase with the woofer this i followed from the xover pro software plus most other information suggest + to - for that filter
others have stated that the foam could be eating up my bass signal?
now that these graphs are showing response, what do they represent in the lower end
is the Db level down due to this?
cheers speedie
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Can I assume that now you can measure, you'll be simming your crossovers? If so, forget the baffle step per se, and just make it flat.
Of course you'll have to work out how to take anechoic measurements. Some of these fluctuations could be room related.
Again depends on whether you will sim or not. If not, then I probably would.
Speedie, in your shoes I would take one graph as it is for total with now crossover. Then sans crossover individual woofer and tweeter responses without moving the mic, along with individual impedance responses. The former in box with the mic midway between centres at 1.2m, the later with WT3, still in box. Then I would feed individuals and now crossover to a simulator. I would fix the simulator to mimic now response, so I am sure it follows. Then I would manipulate for a flat but gently tilting response 200Hz-20KHz -2dB with lower bass level meeting to 200Hz and going as low as possible. Here removing the egg crate dense foam and see if it damps too much test move comes in to play. Then I would make that crossover and would listen. If your now sound can be described as shallow, hollow, and bright, then off you go starting.
An update
I had my work shop amp drop the left channel which is very frustrating when in the listening mode
So I unpacked my emotiva products XPA 2 300 Watt amp/ UMC1 Processor / ERC 2 there CD player and hooked then up to the unchanged boxes
Connected a better sub woofer into the game
And am now really happy with the results
It makes a big difference pushing these boxes with some real power
I have started on the tower MTMW project and will post some photos of there construction
I have not been on the site for some time now
Hope that all are well and nice to read some of the current postings
Cheers speedie
I had my work shop amp drop the left channel which is very frustrating when in the listening mode
So I unpacked my emotiva products XPA 2 300 Watt amp/ UMC1 Processor / ERC 2 there CD player and hooked then up to the unchanged boxes
Connected a better sub woofer into the game
And am now really happy with the results
It makes a big difference pushing these boxes with some real power
I have started on the tower MTMW project and will post some photos of there construction
I have not been on the site for some time now
Hope that all are well and nice to read some of the current postings
Cheers speedie
Welcome back speedie 
It's funny how a break and a different approach can really change things isn't it!
I listened to my MTM's for a year with their original crossover but was never completely happy, I then completely redid the crossover, and the difference was substantial. I'm very happy with them now.
Tony.
It's funny how a break and a different approach can really change things isn't it! I listened to my MTM's for a year with their original crossover but was never completely happy, I then completely redid the crossover, and the difference was substantial. I'm very happy with them now.
Tony.
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