Fostex fe108 eSigma in OB ?'s

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Rudolf thanks for that image, it is exactly what I was thinking and then put a non-inverted BIB on top :)

Robert perhaps I will go for them and give them a try, as they would go lower and they're only about $60 or so more for the pair.. Yeah a 4'' driver can only deliver so much even in a BIB.. There is lot's of music I know very well where the lows are missing, but they do a good enough job I guess.

Now I need to go pick a daisy : Alpha, Goldwood, Alpha, Goldwood etc etc etc..:D
 
ok, i think i get it;
and those were down 5dB by 50Hz, had a 10dB bump around 35Hz, then fell off, was down ~15dB from the bump @ 20.
you prolly liked the bump centered around 35 Hz, where you're used hearing bass? (& just below where austins & bibs have run out of steam). :)

yeah, i used those bag ends as corner deflectors for the austins you ended up with. 96 db sens, they matched up/filled in well.
 
Hi Serenechaos, I love bass! I hate boom, but I love bass. Those Khorns are supposed to play down to 28Hz, maybe to squeeze in the last key on the piano? Not that anybody plays it (or maybe they do play it, but I can't hear it, hmm...)

Hi DaveCan, according to MJK, "The H frame’s external dimensions are 21” wide, 21” tall, and 16” deep. The open area is a 20” by 20” square." It looks like Martin's strategy is to just build an H-frame capable of holding the driver, and then keep the "depth" on each side of the woofer to about 7.5" (so ~15" of depth plus whatever for the baffle itself?)
 
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Okay, decided to put in an order for the Goldwood 18's and install them in H-Frames and plop my BIB's on top for now.. Then later on the hope is to try full on OB baffles in the mirror imaged shape of the Carver Amazings, using the Goldwoods and my 108 or a 6'' Fostex etc... I've always liked the shape of these, and one could scale them down to whatever size fits and works in your room etc..
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Well I ordered the Goldwood 18'' drivers and built MJK's H-Frames.. Wow:D


Very nice quality of bass that matches really well to the fe108sigmas.. The lows are some of the best articulate clean and natural I've ever had dialed in to my system.. I would of never thought that a cheap 18'' could sound so good or accurate compared to some smaller sized woofers.. The sound I'm getting even though I have no choice to have them near the corners, is just excellent and very real sounding, no doubt the open alcove to the hall helps with this corner placement.. When you listen to an upright bass for instance, it actually sounds like it should with no artificial extras thrown in. As I've been playing with settings I had the funny thought while engrossed in listening, that this is like bass that has been showered and all cleaned up lol.. Just pure and clean with no bling etc.. If anyone has had doubts that an 18'' driver cannot track well or be accurate you are surely mistaken...

A big thanks goes out to Martin of course, and to Mike from Q Components here in Canada, for excellent customer service and great pricing comparable to our US counterparts etc..

My BIB cabs are now modded back to the basic design.. I cut off the extra I had when I was using them inverted firing at the floor, to now firing upright at the ceiling as they are designed originally.. Stacked upon the H-Frames and tilted forward down towards the listening position, using rubber door stoppers to tilt up from behind, the center of the 108's now stand at about 49.5 inches off the floor .. This has been a great benefit to lifting the sound stage to a more realistic presentation in my application, and proves to me that a higher driver height is much better than lower.. Previously in the inverted method they were about 35'' or so off the floor to driver center.. The musicians come across as lifelike standing or sitting at proper level invisible between the speakers, it's really cool and incredible on some recordings :)

I added standard 2''x6'' spruce building lumber via L brackets to the sides of my BIB cabs and also made the cd rack and stereo stand out of the same building lumber using an old manual hand saw, talk about old school lol..

The H-Frames are made from 3/4'' ply with the center baffle centered on 7'' from the front edges, and I added the slats in front because of my 6 month old Black Lab puppy who likes to poke her nose into things lol... The drivers are mounted behind the baffle taking advantage of their built in front edge gaskets... I built everything to spec except I used 3/4'' ply all around and mounted the baffle on center at 7'' from the front edge, rather than the 7'' to the baffle that Martin recommends in the design.. I figured mounting the drivers from behind still put them within spec, and keep the back of the woofers well within the cab still..

It's also pretty cool that a standard 2''x6'' is a perfect fit for making a CD rack, and of course now sitting on that solid Spruce they sound even better by picking up the vibe and soul of the wood:p lol :)

All in all for the price of admission, WOW!!! :cool: My crossover is at about 77hz, and as you can see on the amp the level is quite low and produces much sound, I'm very happy.. Don't like the sound of the GW in the H-frames at a high x-over level (over 100 +hz or so) as there is coloration, but used as subs, perfecto mondo!!!



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Hi DaveCan,

Fantastic! I love the doorstops.

(a) What is your sub amp?

(b) Is it possible the coloration you hear from a higher-than-77Hz crossover could be due to the proximity of the rear of the H-frame being so close to the wall?

I think Rudolf recently posted a picture of an H-frame (or similar) at a 45-degree angle to the corner -- i.e., the side of the H-frame would align with the BiB baffle.

Very sweet!
 
Thanks Robert :) Yes I should have clarified that in my situation that is what I noticed.. I tried positioning the H-Frames many different ways, and also as you described within my space constraints. I tried them angled out facing the listening position also, but after much experimenting they sound the best at the listening seat in the position they are at now.. I'm very happy as it's not even really recommended to use these so close to the wall in the first place..

The reason I took the gamble is I figured that maybe the immediate opening to the hall may let a person cheat with the placement constraints of an OB style cab, and it works pretty well in my room, quite surprising really...

The sub amp is a Reckhorn A-400 that I got a good deal on new a few years ago from Bob at CSS (another fine company to do business with btw)

What's really cool to me is that for the money invested in drivers, I'm living with some real seriously decent sound:cool:

My next step when I get the fever to change things up will be to try full on OB on solid wood baffles in the look and shape of the Carver Amazing cabs.. Also I may move on to a more efficient and larger driver than the 108 like a 6'' etc and go from there.. I've been happy with the 108's now for a good few years and love them, however I can see that trying something a bit bigger one day may have it's advantages and fun :) Heck people even get to tweaking their $10,000 + drivers, I'm pretty happy just enjoying the music if it's nice, clear and detailed, and that's what is going down at my place.. Great synergy with the Decware Taboo amp and the 108's, they really like each other.. Sometimes more volume would be nice but for the most part it can still get comfortably loud and also saves the hearing etc..

Should also mention that the BIBs are left unfiltered running full range, and all the wood was just sanded and left unfinished and is rustic in quality but works for me, plus it smells like nice new construction in here now lol...

Oh yeah, the rubber door stops work great and are the cat's meow for easy tilt tweaking etc, and were cheap in packs of three at the dollar store... You can see that under the right channel H-Frame I used a few door stops as the floor is sloping there.. It's an old house hand built by a man after he got back from WWII, and the plan is to take it down and build on the property eventually, but for now it's home :)

PS. If anyone is interested in hearing the CD's in the top view pic here's a few links, great disc's... The live Jesse Winchester near the end of the performance brings tears to the gal next to him.. Good stuff..

http://www.youtube.com/watch?v=SyFc-pbcO94
http://www.youtube.com/watch?v=5uKGWpqnS8E
 
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