7.3 Variations

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I should have used a more aggressively raked blade. Wanted a nice clean cut. It is a pretty long 45 to cut in one pass. It was made longer by the fact that I used 18mm on face. I will have the up and running this evening. As you can see, I have used screws so that i can get to everything for adjustments. These are just test boxes. I will redo with better plywood if I like what i hear.
 
Lookin' good Buzzforb! Looks like you need to sharpen that table saw blade, too! :)

I should have used a more aggressively raked blade. Wanted a nice clean cut. It is a pretty long 45 to cut in one pass. It was made longer by the fact that I used 18mm on face. I will have the up and running this evening. As you can see, I have used screws so that i can get to everything for adjustments. These are just test boxes. I will redo with better plywood if I like what i hear.

Even with a really aggressive and very sharp blade (combo / rip cut worked better for me here than a ATB "finishing" blade), it's still pretty tough to completely avoid any burn or chatter on this deep a bevel in plywood. If you do decide to rebuild with a better quality multiply, I'd suggest you leave a little allowance for cleaning that up with 60or80G on a long block.
 
Even with a really aggressive and very sharp blade (combo / rip cut worked better for me here than a ATB "finishing" blade), it's still pretty tough to completely avoid any burn or chatter on this deep a bevel in plywood. If you do decide to rebuild with a better quality multiply, I'd suggest you leave a little allowance for cleaning that up with 60or80G on a long block.

I did, just in case.;)
 
It is my current opinion that the 7.3 needs a woofer with any of the smaller enclosures if listening in medium size room. Nearfield is better, but at 5-6ft, it will not match a small moniter such as my Missions in bass. I would estimate that it has level response down to 100 maybe higher in a larger room. I do not believe this enclosure related but is the nature of the driver. If in a larger enclosure like Scott's Maeshowe, you make get lower. It does what it does very well, but some low register stuff just sounds thin. I am including some voices in this grouping. More to come.
 
I'm currently running a cheapie subwoofer that can be crossed over relatively high. Though this subwoofer will soon be ditched for a CSS SDX10 on a Bash 300S plate amp as soon as next week. I'm highly looking forward to using the SDX10 as everything I've read say it's sheer accuracy is stunning and it's able to be XO'ed high enough for use with small full range drivers such as the 7.3 and others.
 
I don't want to discourage anyone from this driver. I think it will be phenomenal with a sub. All this is said based on my rather larger open ended room. My comments are preliminary and I have very little listening time. Right now, I would say the 10.2 is a true FR where the 7 is perfect for a FAST setup.
 
I don't want to discourage anyone from this driver. I think it will be phenomenal with a sub. All this is said based on my rather larger open ended room. My comments are preliminary and I have very little listening time. Right now, I would say the 10.2 is a true FR where the 7 is perfect for a FAST setup.


Funny that, I currently listen to a Pensil 10.2 and just started a FAST build with the 7.3 and the Seas L26ROY :)
 
I also have Pensil 10.2's and agree with you about it's fullness of sound; though I've since passed them onto my Father. I had played around with a friend's CHR-70's recently and found that they image very well for being MA's entry level driver, so I decided to give the 7.3's and Mark Audio another shot with some added bass augmentation.

I've found that I favor a sealed enclosure for enhanced transient response and more friendly room placement versus the finicky nature of ported enclosure placements. Though their response is more linear than ported I believe it's perfectly fine if you intend on crossing over your woofers around 100hz.

I'd also be interested in using the Eminence Alpha 15A's that I see people using for their FAST systems, but I'm somewhat at a loss on how to use MJK's worksheets. If anyone has any information they could pass along to me about proper panel sizes and everything else I'd need to know to build an H-Frame using the 15A's I'd be more than appreciative. I've also been tossing around the idea of running OB with the 7.3's like I've seen in another thread, though I don't agree with adding a filter to a full range so maybe it's just a shot in the dark. I'd run them unfiltered and cross the woofers over as high as I can with my plate amp, which happens to be 150hz. I'm not sure if that's high enough for the 15A's to integrate well enough with an OB 7.3. Any advise?
 
Dave suggest putting the a7 in an aperiodic enclosure if trying to use in non OB FAST setup. I believe the reasoning has to do with wanting to load the driver somewhat, but be able to reduce standing waves at the same time. I am new, so none of thisi is certain, just from a poor memory of past conversations. I believe the filter is needed for an OB setup for this same reason. The driver will have no reinforcement from an enclosure, but will still try to reproduce the full spectrum response. Could be troublesome for driver life. I think it is like a woofer in a tapped horn. If you are not careful, it will exceed its max Xmax trying to reproduce what the box is tuned to. Take all that i have said with a grain of salt. Dave and others are the ones to ask. If you are interested, maybe we can procure him to com up with a design. I was thinking of just sticking it on top of another 2.5way design, minus the tweeter.
 
I've thought that the Peerless 830667 8" driver in about 30 litres sealed would be a good match for the 7. Crossover @ 200hz 1st order on both. F3 ~ 45 or so with a decent (but no spectacular) Xmax on the 8". That should increase both dynamic range and bass with a minimum of phase twisting. The 10" version (830668) might sound a little warmer and give a tweak more deep extension.
 
Last edited:
frugal-phile™
Joined 2001
Paid Member
There are lots of suitable midbasses that can be used on the bottom. Once you remove the need to meet a typical tweeter, most of their problems disappear.

I'm working on a FAST idea with A7.3 -- i haven't had the break-thru i need to get the cab right yet, a number of conflicting requirments that haven't come together yet, but i am going to use 4 SDX7 per side on the bottom. Sealed.

dave
 
Dave, what I meant to say that 4 SDX7 per side seems like quite a LOT of LF enforcement... even 1 SDX7 units should be no slouch. Again I haven't heard the SDX7 and have no experience with the driver, but specs look good. You've recently had excellent results with 2 x EL166 per cab, so 4 x SDX7 sounds scary :).

-Zia
 
Please keep me informed. I must admit I love the raw sound you get from the 10.2. Perfect for quality jazz musicians and singers with throaty voices.

I will. I just put together one test cabinet to get an idea if my plans will work. I made some quick and dirty measurements and put together a very rough filter in the Hypex AS2.100 DSP I am using for this project, crossing at 200hz 4th order LR. 5 DB shelf from 750 hz or so on the Alpair 7.3 for baffle step....

This thing sounds WAY better than it ought to. The L26ROy is firing to the side but the integration is already VERY good. This is going to be good!
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.