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Discussion Starter · #1 ·
It looks like Mayhem13 is throwing out the coaxial poll and going a different direction. I am starting this thread to see how many people would be interested in pursuing this. Hopefully Tom Danley is still interested in helping with this. Post here and let me know.
 

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Has Tom expressed interesting giving access to this technology to the DIY community?

Danley speakers are for sale. But I'm not so sure about the we express interest and Danley provides aspect you seem to be implying. Am I wrong here?
 

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Quote:
Originally Posted by NEO Dan /forum/post/16997567


Has Tom expressed interesting giving access to this technology to the DIY community?


Danley speakers are for sale. But I'm not so sure about the we express interest and Danley provides aspect you seem to be implying. Am I wrong here?

It's madness.


Tom said he MIGHT be able to help with optimizing a crossover, once a final design is complete. Somebody's got a bunch of work to do first....
 

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I would be interested in a simple 2 way for surround duty but even more interested in a MTM with 2 8" woofers helping out on the bottom end ala Triple 8. Maybe start out with the 2 way and then convert to a MTM as well.
 

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8" pro woofers are pretty weak in the bass, these will almost have to be 3-way, except maybe the surrounds. I don't think they will even reach down to a sub well. Maybe down do a midbass unit? Although the 18 Sound 8NMB420 I tested some time ago actually had alright bass. Don't know if the 8CX400F is the same.
 

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Discussion Starter · #10 ·

Quote:
Originally Posted by augerpro /forum/post/16998364


8" pro woofers are pretty weak in the bass, these will almost have to be 3-way, except maybe the surrounds. I don't think they will even reach down to a sub well. Maybe down do a midbass unit? Although the 18 Sound 8NMB420 I tested some time ago actually had alright bass. Don't know if the 8CX400F is the same.

The 8NMB420 has an fs of 60 and the 8CX400F has an fs of 64. Looking at the graph for the 8NMB420 it is a little flatter on the low end, but they both drop off at the same point. Mark is getting the 8CXT down to around 70Hz actively, fs of 76. Do you think we could get the f3 down to 80Hz using the 8CXT or the 8CX400F in a ported enclosure with a passive crossover?
 

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Discussion Starter · #11 ·

Quote:
Originally Posted by tsloms /forum/post/16998300


I would be interested in a simple 2 way for surround duty but even more interested in a MTM with 2 8" woofers helping out on the bottom end ala Triple 8. Maybe start out with the 2 way and then convert to a MTM as well.

What sucks, that is the exact direction that the polls led to in Mayhem13's threads. All we were down to, was picking the coaxial and LF drivers. Mayhem13 used the excuse that arguing over which coax to use as a reason to throw it out. In a poll type of situation you are going to have people wanting different drivers used no matter what type of driver you are discussing. Mayhem13 never did want to use a coax and I think he thought that most people felt the same as him. I think he thought that he would be able to put the coaxial talk to bed with that poll, so I think it threw him for a loop when the coaxial won the poll.
 

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Quote:
Originally Posted by mjg100 /forum/post/16998473


The 8NMB420 has an fs of 60 and the 8CX400F has an fs of 64. Looking at the graph for the 8NMB420 it is a little flatter on the low end, but they both drop off at the same point. Mark is getting the 8CXT down to around 70Hz actively, fs of 76. Do you think we could get the f3 down to 80Hz using the 8CXT or the 8CX400F in a ported enclosure with a passive crossover?

Hey MJG,


You might not want my feedback in your thread, but I think one reason Brandon does not want to push the coax that low is that it tends to sacrifice the midrange performance and clarity, which is very important for HT. If you've ever listened to a 3way design without the woofer connected, letting the mid run full range and then adding the high pass into the mid, so it no longer has to do low end duties as well, you will know what I mean. It can be a night and day difference. IMO, it usually opens the midrange up a lot and it can go from rather muddy to very clear and open when the mid no longer has low end duties as well. You are just trying to get too much out of a single driver and rather than getting excellent bass and midrange, you end up compromising both. If you have dual drivers sharing this duty, as in an MTM it can be different.
 

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Quote:
Originally Posted by mjg100 /forum/post/16998513


What sucks, that is the exact direction that the polls led to in Mayhem13's threads. All we were down to, was picking the coaxial and LF drivers. Mayhem13 used the excuse that arguing over which coax to use as a reason to throw it out. In a poll type of situation you are going to have people wanting different drivers used no matter what type of driver you are discussing. Mayhem13 never did want to use a coax and I think he thought that most people felt the same as him. I think he thought that he would be able to put the coaxial talk to bed with that poll, so I think it threw him for a loop when the coaxial won the poll.


Mayhem was set unfortunately from the start NOT to build a coax. His mistake was to enter this into the poll about a coax and then having it blow up in his face. It seems to me that this forum wants to build a MTM with a coax. He should have just continued to build what he wanted to instead of trying to entertain a coax. I wish him the best on his build though.
 

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Interested.


Question is... Everyone can add to the discussion and ideas but who is actually going to build the first test mule and do the grunt work? Tom is a very busy guy. He offered to help with the crossover...Maybe. He's not going to design the thing for us.
 

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Tom has commented about a particular B&C 8" coax having a fairly optimum horn throat to cone transition and being a good option. Since he has some experience developing a synergy horn crossover for it, it may be the best opiton, as long as he doesn't view it as a conflict of interest.


Here is a decent place to buy them from:
http://www.magnumcaseworks.com/Loudspeakers.html


You might even be able to setup a group buy directly form the US distributor.


Most DIYers are a bit cheap and this may be a little rich for most people's blood though.
 

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Discussion Starter · #17 ·
Augerpro has a B&C 8cxt for testing and he said he should have the results this weekend. That should tell us something. If possible I would like to do this as a 2-way. If we can get to f3 of 80Hz then that would work. I am not positive but I think the f3 of the Sparks is around 70Hz. If we can't get to 80Hz then we need to either add woofers to the design or use them with bass bins.


In the other thread Penn offered to buy the coaxial for testing. If Penn is still open to that we could look at one of the other coaxials such as the 18 Sound 8CX400F.
 

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Quote:
Originally Posted by mjg100 /forum/post/17000009


Augerpro has a B&C 8cxt for testing and he said he should have the results this weekend. That should tell us something. If possible I would like to do this as a 2-way. If we can get to f3 of 80Hz then that would work. I am not positive but I think the f3 of the Sparks is around 70Hz. If we can't get to 80Hz then we need to either add woofers to the design or use them with bass bins.


In the other thread Penn offered to buy the coaxial for testing. If Penn is still open to that we could look at one of the other coaxials such as the 18 Sound 8CX400F.

I think we should do both 2-way and 3-way options. The crossovers should be pretty similar and it'll give more flexibility for budget/needs.
 

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Discussion Starter · #19 ·

Quote:
Originally Posted by dlneubec /forum/post/16998547


Hey MJG,


You might not want my feedback in your thread, but I think one reason Brandon does not want to push the coax that low is that it tends to sacrifice the midrange performance and clarity, which is very important for HT. If you've ever listened to a 3way design without the woofer connected, letting the mid run full range and then adding the high pass into the mid, so it no longer has to do low end duties as well, you will know what I mean. It can be a night and day difference. IMO, it usually opens the midrange up a lot and it can go from rather muddy to very clear and open when the mid no longer has low end duties as well. You are just trying to get too much out of a single driver and rather than getting excellent bass and midrange, you end up compromising both. If you have dual drivers sharing this duty, as in an MTM it can be different.

I understand what you are saying. I took some small speakers (manufacture gives 47Hz as f3) and using a Behringer CX2310 I have them crossed at 100Hz. I have placed three sealed subs under all three front speakers to cover 40Hz to 150Hz. I like it lapped better than crossed. Moving the small speakers up to 100Hz really opened them up.


From everything that I have read the B&C 8CXT is a very dynamic speaker. Mark Seaton's Sparks uses one in an active design and I believe the f3 is around 70Hz. Every post and review that I have read about that speaker has been raving about it. So it looks to me that it can be done with good success. 70Hz would be great, but I would be happy if we could hit 80Hz. Since I have bass bins/MBMs I could even use it up higher, but that is something that would work for a lot of people and I am trying to get this to work for a group rather than just one person.
 

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Quote:
Originally Posted by mjg100 /forum/post/16998473


Do you think we could get the f3 down to 80Hz using the 8CXT or the 8CX400F in a ported enclosure with a passive crossover?

DanN answered this spot on, could,yes, should, not in my opinion. Just one person's opinion of course.

Quote:
Originally Posted by mjg100 /forum/post/16998513


What sucks, that is the exact direction that the polls led to in Mayhem13's threads. All we were down to, was picking the coaxial and LF drivers. Mayhem13 used the excuse that arguing over which coax to use as a reason to throw it out. In a poll type of situation you are going to have people wanting different drivers used no matter what type of driver you are discussing. Mayhem13 never did want to use a coax and I think he thought that most people felt the same as him. I think he thought that he would be able to put the coaxial talk to bed with that poll, so I think it threw him for a loop when the coaxial won the poll.

To be fair I have my doubts that we could have pulled of the coax option with the budget listed. It wouldn't be much more, but still it would be more than $750 most likely. $850 would probably work with the dual 8" woofer option as midbass support.
 
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