Hello to all,
I've been seeing alot of designs using MTM 2 way and TMM 2.5 way .
To those who've experienced both designs , Whether by listening to commercial speakers or DIY ones, What do you think sounds better between the two designs in terms of imaging , soundstaging and detail retrieval, Given than both use similar driver and similar baffle width?
Thank you
I've been seeing alot of designs using MTM 2 way and TMM 2.5 way .
To those who've experienced both designs , Whether by listening to commercial speakers or DIY ones, What do you think sounds better between the two designs in terms of imaging , soundstaging and detail retrieval, Given than both use similar driver and similar baffle width?
Thank you
i have not heard those besigns, but i assume an mtm will sound better since its more symmetric. the distance between each woofer an tweeter is smaller, so there will be less interference at crossover frequencies, thus a better sound.
i could be wrong, since i dont exactly know what the 0.5 way is.
i could be wrong, since i dont exactly know what the 0.5 way is.
MTM vs TMM 2.5
I built a nice TM with a Dayton RS180 woofer and good tweeter.
Sounded real nice, but could not play very loud.
I added a 2nd RS180 for the .5 woofer, and found that the system could play much louder without distortion (expected), and that the upper midrange was much clearer (unexpected).
The textbook answer is that Intermodulation Distortion from a mid-woofer trying to handle both bass and mids is reduced, because the "regular" woofer has less excursion in a 2.5 way TMM system.
Downside is that there are not a lot of TMM 2.5 way designs to learn from, compared to MTM designs.
HTH
-Don
I built a nice TM with a Dayton RS180 woofer and good tweeter.
Sounded real nice, but could not play very loud.
I added a 2nd RS180 for the .5 woofer, and found that the system could play much louder without distortion (expected), and that the upper midrange was much clearer (unexpected).
The textbook answer is that Intermodulation Distortion from a mid-woofer trying to handle both bass and mids is reduced, because the "regular" woofer has less excursion in a 2.5 way TMM system.
Downside is that there are not a lot of TMM 2.5 way designs to learn from, compared to MTM designs.
HTH
-Don
i think that's really one of the things you have to test to know since the characteristic are just plain different
Also you have plenty of ways of designing boths wich will sound different.
I'd tend towards TMM 2.5 ways for myself, but i'd say it really depends on what you want to get.
TMM 2.5 ways is really fun cause it's an elegant design, if you're using the second woofer to compensate for BSC.
MTM 2 way is more special. It does have a more limited dispersion pattern in the vertical plane, wich can be a good thing
i guess the best thing would be to you to build some testboxes of both with same drivers to see what you like most
Also you have plenty of ways of designing boths wich will sound different.
I'd tend towards TMM 2.5 ways for myself, but i'd say it really depends on what you want to get.
TMM 2.5 ways is really fun cause it's an elegant design, if you're using the second woofer to compensate for BSC.
MTM 2 way is more special. It does have a more limited dispersion pattern in the vertical plane, wich can be a good thing
i guess the best thing would be to you to build some testboxes of both with same drivers to see what you like most
mtm i like,but I really think it all depends on the woofers,if they are not efficent use mtm,you get more efficency,better overall.
Generally speaking, the bottom M in a TMM does not "pass over" to the tweeter, thus attenuating lobing.MaVo said:
In my opinion matching up the radiation pattern in the crossover region is a good thing. So from this standpoint, a TMM 2.5-way would be preferable to the same drivers in an MTM configuration - but neither is what I'd do if the T is a direct-radiating dome.
Duke
Duke
Marchel,
I would build a full frequency range 3-way TMW. I would try to get clever on the large bass cabinet design to minimize the apparent size. There are several good DIY 3-way designs that can be cloned in custom cabinets.
I would build a full frequency range 3-way TMW. I would try to get clever on the large bass cabinet design to minimize the apparent size. There are several good DIY 3-way designs that can be cloned in custom cabinets.
" but neither is what I'd do if the T is a . "
Well, I already ordered a pair of peerless HDS tweeters, But would'nt you use direct-radiating dome
In such designs?
Linesource,
My options on the midbass are still open, Cause I havent ordered midbass yet, I 'm thinking of usher 8945 A or P 7" woofers, 2 per channel ,.
OTOH , A 3 way with 10" woofer should be louder, I'm thinking about using Seas aluminum 10" woofer for a 3 way design and use the usher 7" as mid for its low distortion. but so far I havent seen a design that uses this combination and Madisound cannot design a crossover system for it , cause they dont carry usher brand.
Well, I already ordered a pair of peerless HDS tweeters, But would'nt you use direct-radiating dome
In such designs?
Linesource,
My options on the midbass are still open, Cause I havent ordered midbass yet, I 'm thinking of usher 8945 A or P 7" woofers, 2 per channel ,.
OTOH , A 3 way with 10" woofer should be louder, I'm thinking about using Seas aluminum 10" woofer for a 3 way design and use the usher 7" as mid for its low distortion. but so far I havent seen a design that uses this combination and Madisound cannot design a crossover system for it , cause they dont carry usher brand.
Marchel,
With a dome tweeter I'd do a TMW, probably using a 2" or 3" dome midrange. This results in less discrepancy between the on-axis response and the reverberant field response in the crossover regions, something that I believe makes an audible difference.
Duke
With a dome tweeter I'd do a TMW, probably using a 2" or 3" dome midrange. This results in less discrepancy between the on-axis response and the reverberant field response in the crossover regions, something that I believe makes an audible difference.
Duke
A properly D’Apolitoed MTM will be less sensitive to the room reflections. Driver positioning is critical in regards to the crossover point.
TMM may give a slightly higher resolution on the lower end.
TMM may give a slightly higher resolution on the lower end.
Dear all,
This is just an update on my project.😉
I recently ordered 4 woofers and the package has just arrived, On time and in perfect condition.
I would like to thank madisound and Fedex for fast delivery.
Back on the topic:
The woofers are more beautiful in person than what I saw on the web. The construction seems very good, All in all, I have nothing to complain about the peerless woofer and tweeters that I have.
Below is the picture on the woofers and tweeters.😉
You can say that I'm exited right now. 😀
This is just an update on my project.😉
I recently ordered 4 woofers and the package has just arrived, On time and in perfect condition.
I would like to thank madisound and Fedex for fast delivery.
Back on the topic:
The woofers are more beautiful in person than what I saw on the web. The construction seems very good, All in all, I have nothing to complain about the peerless woofer and tweeters that I have.
Below is the picture on the woofers and tweeters.😉
You can say that I'm exited right now. 😀
Attachments
Hi,
Whilst TMM 2.5 way is theoretically superior to a 2 way MTM you are
pretty much stuck with 6dB baffle step compensation, whilst for the
MTM 2 way you can use (or omit) any amount of BSC you like.
http://www.diyaudio.com/forums/showthread.php?postid=1371987#post1371987
🙂/sreten.
Whilst TMM 2.5 way is theoretically superior to a 2 way MTM you are
pretty much stuck with 6dB baffle step compensation, whilst for the
MTM 2 way you can use (or omit) any amount of BSC you like.
http://www.diyaudio.com/forums/showthread.php?postid=1371987#post1371987
🙂/sreten.
sreten said:
I guess that's one of the advantages of 2 way mtm over 2.5 way.
But what about the sound quality?
I think If you decrease the BSC to gain sensitivity, It will sound thin , Even with a sub, crossed at around 100hz , Right?
Anyway, Is having a 6db BSC, make the speaker sound bloated in the bass?
Both 2-way MTM and 2.5-way (MTM or TMM) can be made with roughly the same tonal balance (baffle step compensation), efficiency, acoustic phase and low-end maximum SPL.
The main differences are:
- Vertical dispersion and phase alignment issues above and below the listening axis (mostly above the mid-treble XO frequency in 2.5 way and below in 2-way MTM)
- upper midrange detail - in 2.5-way all signal goes to one midwoofer so the static / kinetic friction threshold will appear lower compared to the signal (in 2-way each of the midwoofers gets 6dB less upper midrange signal) so in theory 2.5 way should lose less detail.
- xover components price (2.5-way being more expensive)
- it is easier to make a separate chamber for the tweeter in 2.5-way TMM, isolating the tweeter from the sound pressure in the midbass chamber, it can also be wedge-shaped in order to help supress the up-down standing waves.
The main differences are:
- Vertical dispersion and phase alignment issues above and below the listening axis (mostly above the mid-treble XO frequency in 2.5 way and below in 2-way MTM)
- upper midrange detail - in 2.5-way all signal goes to one midwoofer so the static / kinetic friction threshold will appear lower compared to the signal (in 2-way each of the midwoofers gets 6dB less upper midrange signal) so in theory 2.5 way should lose less detail.
- xover components price (2.5-way being more expensive)
- it is easier to make a separate chamber for the tweeter in 2.5-way TMM, isolating the tweeter from the sound pressure in the midbass chamber, it can also be wedge-shaped in order to help supress the up-down standing waves.
Navy_44 said:
This is not true. Of course, there is SOme room for BSC adjustment in a 2.5 way design by adjusting the .5 woofer's midrange contribution. But if you reduce BSC too much this way, the design can no longer be called "2.5 way" in a strict sense. And there will be an interaction problem between the tweeter and the .5 woofer.
Navy_44 said:
I don't get that. I would think that since the upper mids are shared between the two midwoofers in an MTM, there would be less excursion and lower distortion compared to a TMM.
One thing that hasn't been mentioned is that a TMM can have less baffle around the tweeter, which tends to give an airier sound.
Jay_WJ:
Reduced BSC 2.5-way can be named "2.75-way" and be made MTM in order to solve the lower midwoofer - tweeter interaction problem. I have seen the XO schematics of such designs (with cascaded filter approach and the lower midwoofer inductor value as low as 0.82mH with some BSC in the main filter).
Audiobomber:
The upper mid excursion is of the order of small fractions of a milimeter so it should not be critical in terms of distortion. German magazine Klang und Ton sometimes makes distortion measurements at two SPL levels 10dB apart - and in most cases the biggest difference is at the low end where the excursion becomes an issue.
I know there is little experimental evidence to the static friction problem available to the public, but for some reason Scanspeak claims that high loss suspensions do lose detail so they are in favor of low loss suspensions.
Reduced BSC 2.5-way can be named "2.75-way" and be made MTM in order to solve the lower midwoofer - tweeter interaction problem. I have seen the XO schematics of such designs (with cascaded filter approach and the lower midwoofer inductor value as low as 0.82mH with some BSC in the main filter).
Audiobomber:
The upper mid excursion is of the order of small fractions of a milimeter so it should not be critical in terms of distortion. German magazine Klang und Ton sometimes makes distortion measurements at two SPL levels 10dB apart - and in most cases the biggest difference is at the low end where the excursion becomes an issue.
I know there is little experimental evidence to the static friction problem available to the public, but for some reason Scanspeak claims that high loss suspensions do lose detail so they are in favor of low loss suspensions.
Navy_44 said:
Now we're on the same page. BTW, it should be called "2.25-way," not "2.75-way." Right? 🙂
I believe that this 2.5 vs 2-way issue should be addressed by an objective experiment, not by speculations.
marchel said:
Hi,
I believe a 2.5 way when it works is better than MTM and also more
room friendly as the MTM axis is by definition the tweeter, making a
tall speaker for the MTM compared to the TMM.
Certain drivers do not need 6dB of BSC, some need more, the
latter are better for 2.5 ways as you have some tuning flexibilility.
2 way TMM's do exist so 2.1 to 2.4 ways are possible.
🙂/sreten.