planet10 said:
What about a traditional BR for the SDX7's instead of a TL? In WinISD Pro they seem to model pretty well down into the mid-30's, but the enclosures are all just under 1cf. Of course, if you go with an EBS of -3dB, you get a 2.15cf enclosure with response down into the mid-20's.
And I know it's common knowledge, well... factual proof actually, that removing the bass from a driver improves its mid/top performance. But I have to say, even while still playing fullrange (with the sub just simply added in), the 103's still sound completely amazing all the way through their range. I guess where you would see the most improvements would be at higher SPL's, which would make sense. Even then, they still compose themselves very well.
chrisb said:
Isn't the "Fonken" enclosure for the 127 considered more of a BR than a TL? All it looks like to me is two thin rectangle ports split into six individual ports that run almost all the way to the rear of the enclosure. Just asking...
If the Fonken is nothing more than a BR, then why couldn't I just design the dual SDX enclosure the same way and port it the same way? I'd rather have the drivers in the front anyway for looks as well as for sound. That way, I could also have the drivers mounted much higher up in the enclosure as well.
planet10 said:
Height isn't much of an issue as if it's too short, I can just build small riser bases for them. I doubt being too tall would be a problem either.
Right now, my 103's are exactly 47" (center of cone) off the floor. With listening heights anywhere between 38" - 44", there's no change in sound. Even standing (I'm 6'1" or 185.4 cm), the sound doesn't change, at least not enough to make a negative difference.
They are very sensitive to toe-in and sweet-spot position however. Even a half inch movement by me or the speakers makes a big difference.
Also, I've modeled a sealed enclosure in WinISD Pro, and it wants to cram both drivers into 0.54cf of airspace! That one starts rolling off at 150Hz or so and is down -3dB at 73Hz. That's just about as high as the 127!
Of course, room gain will help that out a bit, but if I'm going to spend $400 on a set of SDX7's, I want them to do better than a pair of $90 fullrange drivers in the bass department. You know what I mean, jelly bean?! 😀
chops said:
Nobody said the Fonken is a TL. It's an Onken. Chris's words were 'As it is, the TL cabinet [as in the woofer box the Fonken is sitting on] does place the FE127 a bit higher than some might want.'
An Onken uses a comparatively large total vent CSA, which is why they are long, but the individual size is also quite small, and having a high aspect ratio, they are rather resistive, making this particular variation of the concept analogous to an aperiodic design.
Scottmoose said:
Thanks for clearing that up Scott. I didn't know that about the Onken. So would that same kind of design work with the SDX7's?
Just wondering if you guys might know...
Do you think I'll have to have any series resistance when I put these 103's in my vehicle's dash? And if so, would it be alright to have the resistor at the amp output which will be roughly 15-17' away from the driver?
Do you think I'll have to have any series resistance when I put these 103's in my vehicle's dash? And if so, would it be alright to have the resistor at the amp output which will be roughly 15-17' away from the driver?
BTW, I just wanted to add that I find it very difficult to understand how I can get so much pleasure out of a pair of drivers that only cost $38 each on a thrown together system.
I very seriously think that I will be replacing my my main system's loudspeakers will fullrangers eventually. These blasted little speakers are just too darn good!!!
I very seriously think that I will be replacing my my main system's loudspeakers will fullrangers eventually. These blasted little speakers are just too darn good!!!
chops said:
Before we proceeded with the FonkenWoofTL i had 5 false starts. Those all attempted a fonken-style loading (but it is not possible to have the ports on the side without invoking a huge amount of building difficulty).
In the end (well as far as we got) i was headed sealed, but i've always had a penchant for TLs, and this one just flowed. Restricted by the footprint of the Fonken, and the need to limit the height, this one, althou good, will probably go into the wrong turn pile (they have ended up being stuffed till almost aperiodic). This woofer works so well sealed and has such low distortion that a touch of boost at ~25 Hz can get them flat to 25 Hz in room -- the sealed µFonken woof actually goes lower when configured this way. This also allows more versatility in terms of matching room gain -- one of my pet peeves are bass reflex designs that try to get as low as flat as possible in the modeler, but when put in a room, end up with a big fat bloated wooley peak at the bottom.
If you mount one woofer on the front, the other needs to be on the back -- don't dismiss the importance of push-push. Side firing also makes the XO easier as on-axis the higher frequencies are naturally attenuated.
Further, the SDX7 is too big to fit on the front.
dave
Attachments
chops said:
Probably not.
How low are you taking them? You don't need to attenuate them do you?
You will also have huge "room" gain if using them below ~100 Hz.
dave
chops said:
You are now getting a hint as to why so many are becoming avid FR enthusiasts 🙂
dave
planet10 said:
I was originally thinking that if I were to build the Fonken's, I would keep the baffle flat. But now that I may have help with the build, I might just keep it beveled.
As for the Fonken-Woofer bass-bin, can't the enclosure simply be made deeper to accommodate the length of the Fonken vents? If too much airspace is an issue at that point, then couldn't that same enclosure be vertically truncated to compensate? Then all that had to be done is build a matching base to bring it up to proper height, which could also be filled with sand, etc, etc...
I wouldn't mind at all if the bass-bin was deeper out back than the Fonken on top of it.
planet10 said:
I was originally planning on crossing them over somewhere between 250-350Hz due to the fact that I had never heard them before and was worried about their limited Xmax and power handling. However, now that I have had plenty of time with them playing fullrange, I wouldn't hesitate to have them crossed over at or just above 100Hz, depending of course on how the interior of the dash loads them.
If I do need to attenuate them, all I have to do is adjust the gain on the amp.
The reason I'm using the series resistance now though is because it seems to tame the midrange peak quite a bit and also fatten up the lower midrange a tad.
planet10 said:
Ha! You "ain't" kidden! LOL
My main system that I thought sounded pretty darn good, which I suppose it still does, it just sounds recessed, flat and boring compared to the 103's. And even though the top MTM section is completely open baffle, they don't have a chance on imaging and sound staging compared to the 103's!
Once I added the sub and tube preamp, the little FE103E's just jumped light years ahead of my main system. It's almost embarrassing to even admit that considering I've only spent about $200 total on this system, and it's totally eating up a system that I just invested well over $6k on this year alone!
Cal Weldon said:
Since i haven't heard shadow i can't really say, but the Shadow was not resticted by my footprint requirements and borrows heavily on the loading concepts used in the Fonken, so i'd expect it to have a bit of an edge.
dave
chops said:
Sure... the vents i was playing with are on the order of 18-20" long, and our design brief restricted us to the Fonken footprint. In the end SDX7 sealed works sooo well there is no point.
dave
planet10 said:
Are you going to give the 10'' a go, or have you heard them yet?
http://creativesound.ca/pdf/CSS-SDX10-data-140408.pdf
Dave🙂
PS: anyone working with SDX7 might be interested in these documents:
SDX7-sealed
SDX7-vented
SDX7-ML-TLs
dave
SDX7-sealed
SDX7-vented
SDX7-ML-TLs
dave
Alternate woofer form factor
If the Fonken form factor were to be abandonned, you could perhaps consider dual SDX7's in a "dual coffin" type cabinet. I'm thinking along the lines of the Dual B139 coffin idea. (Refer to the T-line pages) They may well be a good shape to fit cross-ways between the Vampyr's and beneath a wide-screen TV.
Vampyr's & coffins ... 🙂
Doug
If the Fonken form factor were to be abandonned, you could perhaps consider dual SDX7's in a "dual coffin" type cabinet. I'm thinking along the lines of the Dual B139 coffin idea. (Refer to the T-line pages) They may well be a good shape to fit cross-ways between the Vampyr's and beneath a wide-screen TV.
Vampyr's & coffins ... 🙂
Doug
planet10 said:
The MTM is probably my favourite. I keep picturing an FF85K between them for some reason...
Scottmoose said:
Because we already talked about doing that 🙂
XO at or just below the baffle-step... none of the usual MTM XO too high issues.
dave
Since I have decided on upgrading to the 127, I'm surprised no one has mentioned anything about building the Oliva Chang. Any reason why?
And yes, I realize it is not a horn, but a BVR.
And yes, I realize it is not a horn, but a BVR.
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