I ran a sim of what ever info I could glean from the SBA 16 MTM and this what I get. The only thing is my design has the tweeter inverted. Can anybody be so kind to do a sanity check on what i did? much appreciated.
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Satori MTM Bass Reflex Speaker System
Martin J. King 40 Dorsman Dr. Clifton Park, NY 12065 MJKing57
http://quarter-wave.com/Project11/Satori_MTM_Bass_Reflex_Speaker_System.pdf
You could extend the stand-cabinet to a floor-standing and re-calculate the port.
Martin J. King 40 Dorsman Dr. Clifton Park, NY 12065 MJKing57
http://quarter-wave.com/Project11/Satori_MTM_Bass_Reflex_Speaker_System.pdf
You could extend the stand-cabinet to a floor-standing and re-calculate the port.
The crossover from post 41 gave you the attached result ?
What are the box dimensions, how close where the cabinet to the rear wall or room corners? What box size are you using ?
What was the microphone position re the drivers, i.e. on tweeter axis at 1 metre?
Is the cabinet sealed or bass reflex and what volume cabinet are you using?
As an observation on the graph, you still have 5dBs rise from 100Hz to 400Hz, the dips i am guessing are room modes which we all suffer with. if possible can you reduce slightly the peak at 3Khz as well.
What are the box dimensions, how close where the cabinet to the rear wall or room corners? What box size are you using ?
What was the microphone position re the drivers, i.e. on tweeter axis at 1 metre?
Is the cabinet sealed or bass reflex and what volume cabinet are you using?
As an observation on the graph, you still have 5dBs rise from 100Hz to 400Hz, the dips i am guessing are room modes which we all suffer with. if possible can you reduce slightly the peak at 3Khz as well.
The crossover from post 41 gave you the attached result ? <The only change is 10uf is 8.25uf now>
What are the box dimensions, how close where the cabinet to the rear wall or room corners? What box size are you using ? <11.5 x 15 x 22.5 The spk is 4 ft from rear wall and 3 ft from side walls>
What was the microphone position re the drivers, i.e. on tweeter axis at 1 metre? <On axis about 1 meter>
Is the cabinet sealed or bass reflex and what volume cabinet are you using?
<Bass reflex see cabinet size above>
As an observation on the graph, you still have 5dBs rise from 100Hz to 400Hz, the dips i am guessing are room modes which we all suffer with. if possible can you reduce slightly the peak at 3Khz as well.
< Im told that below 300hz it is difficult to make in room measurements and to take it with a grain of salt>
What are the box dimensions, how close where the cabinet to the rear wall or room corners? What box size are you using ? <11.5 x 15 x 22.5 The spk is 4 ft from rear wall and 3 ft from side walls>
What was the microphone position re the drivers, i.e. on tweeter axis at 1 metre? <On axis about 1 meter>
Is the cabinet sealed or bass reflex and what volume cabinet are you using?
<Bass reflex see cabinet size above>
As an observation on the graph, you still have 5dBs rise from 100Hz to 400Hz, the dips i am guessing are room modes which we all suffer with. if possible can you reduce slightly the peak at 3Khz as well.
< Im told that below 300hz it is difficult to make in room measurements and to take it with a grain of salt>
That 3k peak is going to be very noticeable and character defining if not dealt with. For sure would be fatiquing to listen to at higher levels
if I insert an 8 ohm resistor between L1 and Gnd that helps a bit in the Sim. I can get it even better if I change the cap to 11uf from the current 8uf.
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I had a look at the drivers in isolation in Xsim to get a feel for their frequency responses.
Looking at the response maybe a clue why you are still tuning these things, diminishing the 3KHz hump is a pain and I had a play with a tweeter third order by adding another capacitor to your sim. it can be done but you will need some more expensive capacitors.
The rise in the final octave may be an issue for some people but it depends on their hearing.
Your measured response rise may need some more baffle step tweaking, I feel that you need some more inductance in there but I have not used your drivers, so it a basic assumption. Sometimes I just listen to the bass driver in the cabinet as I change inductance values, If you go to far you will kill the character of the Satori's.
I have attached my guess, but it may not be music to your ears.
You can probably drop one of the tweeter resistors as its a fraction of an ohm and tune via the remaining two resistors. If you invert the tweeter you can see a crossover null at approx 2.5kHz. Again you can spend hours changing one component and listening, so crossovers outside the box will help your sanity.
Looking at the response maybe a clue why you are still tuning these things, diminishing the 3KHz hump is a pain and I had a play with a tweeter third order by adding another capacitor to your sim. it can be done but you will need some more expensive capacitors.
The rise in the final octave may be an issue for some people but it depends on their hearing.
Your measured response rise may need some more baffle step tweaking, I feel that you need some more inductance in there but I have not used your drivers, so it a basic assumption. Sometimes I just listen to the bass driver in the cabinet as I change inductance values, If you go to far you will kill the character of the Satori's.
I have attached my guess, but it may not be music to your ears.
You can probably drop one of the tweeter resistors as its a fraction of an ohm and tune via the remaining two resistors. If you invert the tweeter you can see a crossover null at approx 2.5kHz. Again you can spend hours changing one component and listening, so crossovers outside the box will help your sanity.
Attachments
it looks fine.
What do you think when you listen to it, has it addressed your original problem?
can you now relax?
What do you think when you listen to it, has it addressed your original problem?
can you now relax?
I didn't implement the change yet, I was floating it by everyone to see if this looks OK. I think it is easier to implement. I'll try to get to it Monday.
I made the changes to the XO and just from a couple of hours of listening the edge has certainly been taken off the mids. I will take measurements soon.
The response doesn't look bad at all to me, I can imagine it sounds rather good, in fact it may sound fantastic ?.
Does it match your modelling, are you happy with the impedance profile as well ?
It will be interesting to see your comments on the overall sound as you tune it further.
Don't forget to record every separate change in case you go past optimum for your ears and room.
A flattish response or equal amplitude response is not always a good sounding solution, some downward tilt may be needed.
Sometimes you may not even find an acceptable solution and have to reconsider the design.
As you tune the 3Khz hump may come back, hence the trade off and balancing of the overall response.
It is possible what you have now is the sweet spot for the speakers, crossover, and baffle dimensions for this particular design.
Does it match your modelling, are you happy with the impedance profile as well ?
It will be interesting to see your comments on the overall sound as you tune it further.
Don't forget to record every separate change in case you go past optimum for your ears and room.
A flattish response or equal amplitude response is not always a good sounding solution, some downward tilt may be needed.
Sometimes you may not even find an acceptable solution and have to reconsider the design.
As you tune the 3Khz hump may come back, hence the trade off and balancing of the overall response.
It is possible what you have now is the sweet spot for the speakers, crossover, and baffle dimensions for this particular design.
I'll have to check the gate time as I was varying it to see the effect. I think it was <3ms IIRC. I can change the scale yes I'll do that.
I can say it is a lot more tamer and sounds good, not irritating. I do have good configurations management of each change I make so right now I have a 12 ohm resistor shunting across the tweeters. If I want a bit more hi end I can raise the value to 20 or 30 ohm. (some stock values I have or I can do some combo if needed.)