Crazy...sh.... I just plugged my ports &..

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I thought to try pluuging my ports on my fe167e small BR monitors , both active class d subs set at 100hz or so, & I came off the couch in a great hurry......I just got rid of any shout or tizzyness that was left after installing Daves phase plugs, it is all gone, Bass is EXTREMELY tight & focused. 2 hrs later same thing & no change, this is GREAT.. I stuffed the ports tight with acoustic filler I had left over from a project.. everything is better & WTF....? how can this be..... was the ported box conflicting with the subs, it was real good, now it is crazy show off good, for a little 70.00 a pop driver....not much by itself, but with these subs & sealed box,,,OHHHHHHH BOYYYYYYYYYYYYYYYYYYYYYYYYYYYY. I gotta go to sweet spot. be back later... .if you got a pair of subs & have similar set up, plug them damn ports tight & set around 100hz & listen to this... I thought the fe167e had to be in a BR cab.. shows how stuoid I really am......later.
 
Before i tried it I did a 180 & back listen to system,,,,,it is set on 180 now & was before i did this. ...?? O seems to not be the place to be with the subs 4 " forward & directly to outside of monitor stands. I don'y have a clue why , but I am very happy...
 
You've just created an aperiodic cabinet, which behave in a similar fashion to an optimally damped sealed enclosure. They actually go quite low, but have a smooth 12db per octave roll-off when properly designed. Aperiodic is not common any more, but they were, and still are, known for great bass precision and smoothness. I suspect it's integrating better with your sub for several reasons, like that mentioned above, and also eradicating any mild boom the enclosure might have had. You may not have heard it before -it's sometimes the thing we don't realise are a problem that cause the greatest headaches.
 
JandG said:
if you got a pair of subs & have similar set up, plug them damn ports tight & set around 100hz & listen to this... I thought the fe167e had to be in a BR cab.. shows how stuoid I really am......later.

Hi,

I am really enjoying my FE127E in a selaed box. My findings were very similar, while they will not go nearly as low as a reflex or T-line, the bass that is present is tight and accurate. I found a great improvement in the midrange as well. This is very obvious when I only power one driver and use the rear driver as a passive radiator.

Perhaps you could try seal the port off completely or pack it real tight and compare.

While mating with a sub is not really "full-range", I much prefer the sound. You get more bass with the help of the sub, the midbass is tighter and accurate and the midrange is much better.

Cheers,
Gio.
 
What you have done is reduce the excursion of the FE167E's below 100 Hz. This allows the drivers to run both cleaner and louder. You will get even better result by using an HT receiver with the mains assigned as "small" or some other DSP to cut off the FE167E's at ~100 Hz. With no bass, or at least very little bass going to the speakers, dopler (intermodulation distortion) is greatly reduced. Also, since there is little excursion above 100 Hz, you can run the speakers at insane SPL without running into excursion problems.

Once you take the bass off of your drivers, you don't need any cabinet at all to control low frequency excursion. You are now free to go OB or IB. It is folly, though, to use too small a sealed box. This will affect the bottom end of the midrange. Have you heard the term "boxy"? I get great results using an HT receiver with my MLTL's that are tuned to 40 Hz. Rolling them off at 100 Hz effectively removes the cabinet from the sound.

Bob
 
Bob Brines said:
What you have done is reduce the excursion of the FE167E's below 100 Hz. This allows the drivers to run both cleaner and louder. You will get even better result by using an HT receiver with the mains assigned as "small" or some other DSP to cut off the FE167E's at ~100 Hz. With no bass, or at least very little bass going to the speakers, dopler (intermodulation distortion) is greatly reduced. Also, since there is little excursion above 100 Hz, you can run the speakers at insane SPL without running into excursion problems.

Once you take the bass off of your drivers, you don't need any cabinet at all to control low frequency excursion. You are not free to go OB or IB. It is folly, though, to use too small a sealed box. This will affect the bottom end of the midrange. Have you heard the term "boxy"? I get great results using an HT receiver with my MLTL's that are tuned to 40 Hz. Rolling them off at 100 Hz effectively removes the cabinet from the sound.

Bob

Bob:
did you perhaps mean "now free to go OB"? (i.e. if bass limiting the FE127 or FR125 for example)

FWIW, a quick listen to a completely raw pair of the new NeoPhone drivers from Brian Cherry in OB's at the Planet10 love-in and DIY fest this weekend (not a single commercial speaker cabinet in the bunch :D ) ; very promising, but the Visaton B200 still cleans up for a FROB


Gio - the FE127 is more than flexible enough to work very well in the mini-onken style box, as well as TomZ's PAWO cabinet.

(Dave, were are those pictures of the bamboo's?)



cheers
 
This is exciting to me, because now I have heard what a inexpensive Fullrange driver is capable of & will persue fullrangers in many more experiments, OB is something I have to try....but for now I will tweek the fe167e.. next is to dampen the framework of driver with differant material, what do you guys use for that...? I have duct seal & blue tak, I was also thinking of hit glueing diifferant tone woods to driver case.... I will also try to seal them even tight oir seal completely & see if more improvements can be had. I will say that this caught ne off gaurd & did not expect much,,, leaps & bounds in better sonics,, I know running a pair of subs isn't true the the hard core fullrange people, but it is a simpler way for me to listen to my WIDE variety of music, including some very hard music when in the mood. I have learned alot fromn all the feed you all left thanks..
J & G
 
The object is to find something that you like, not follow some illogical creed. Let the reactionary types tie themselves in knots complaining about what you're doing -they're not the ones who are listening to it.

Duct seal is usually good for damping baskets -it's what Dave uses anyway -about 70g on the FE126E, so call it about 100g on the FE167E. I might quickly mention that your idea about trying different types of wood (which resonate differently) seems to be at odds with damping the driver's resonances... (OK, I know the sound of hardwood is 'nicer' than that of metal, but you know what I'm getting at ;-)

Completely sealing the box could be good, providing you amp can handle the impedence spike -with your quasi-aperiodic enclosure as-is, you've likely got some damping going on, reducing the peak a bit. You might want to experiment with a BSC circuit & / or zobel, and phase-plugs too.
 
Can you explain how to set up a BSC curcuit to experiement with, I have lotsa caps & resistors to play with. I also allready have Dave's phase plugs installed, they are very nice..... I am in no hurry to seal off the cab, it is very good now..I will dampen with duct seal this weekend though, that is a must from what I can see on the build of this driver...I will start with 100g & go from there. I would like to play with a BSC curcuit & just need a quck explaination if someone has the time & yes I should do a search,,,,,sorry. Also can the BSC just be installed on the binding post s of speakers..?
J & G
 
Xmax and Power Handling

First of all: I fully embrace the idea. As a matter of fact, my current reference system consists of Manger in a sealed box, crossed actively at 200 Hz to 12" Lambda woofer. It's the best thing I ever made in 25+ years of this hobby, but...
In case of FE167, the big problem I see is a very limited excursion capability of this driver - 0.6mm according to Fostex spec.
I've ran some simulations in WinISD. If we shoot for Q=0.7 (which I don't like, but everybody does), the Fs will be 124 Hz in a 8.5 l box. This set-up will run out of excursion at 0.6 W at 100 Hz. Max power handling at 200 Hz will be only 3.5 W. This will still give about 98 dB SPL. So, if you cross at 200 Hz 4th order, listen at sane levels in a small to medium size room, you may stay within Xmax. If we go for Q=0.5 (which I like much better), the situation becomes even a little worst.
However, if the XO to woofer (you would need a woofer for each channel, not a single sub) is 100 Hz, you will get about 83 dB SPL at Xmax at 100Hz. I'm affraid this is not enogh for good dinamics even in a small room. That's why, these drivers are best suted for horn loading in my opinion.
For wide-range driver + woofer (+ supertweeter?) with XO point aroun 100 Hz, one would need a driver with higer excursion capabilities. There are a number of good candidates: Hemp FR8, Visaton B200, FR125, some Aura 4" drivers (3-5mm Xmax). I am actually looking seriously to try Fostex FW208N for this duty. It has 6.5mm of Xmax and 90 dB of efficiency. It would have to be crossed to a tweeter at about 6 kHz though.
Also FW167 looks very promissing if I can find the way to stay within 1.5mm of Xmax. This one will only need a supertweeter above 10 kHz.

Vadim B.
 
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Scottmoose said:
about 70g on the FE126E, so call it about 100g on the FE167E.

You typically use less on a 167 than a 126 -- the 1x6s have a big magnet overhang, and a lot of the ductseal is actually shaping the rear of the driver to have a lower reflection profile. The 1x7s have smaller shielded magnets and start have a lower reflection profile to start with.

dave
 
planet10 said:


If you can find an HT receiver that you can actually listen to...

dave


:spin:

Try a mid-range Yamaha or Onkyo.

95% of the battle is getting decent speakers. Amps and cables and all the rest of the accoutrements that audiophiles spend big bucks on make up the other 5%. While any two amps will be voiced slightly differently, amps have become a commodity. There isn't a dime's difference between them. Commercial SS, t-amps, gainclones, PP tubes, they all produce a good high quality sound. What you here is the SPEAKERS.

I have three amps that I use for comparisons, a Yamaha HT5470, an SI T-amp and an 8 w/ch 6BX7 PP tube amp. There are slight voicing differences, but bottom line is that there isn't much to choose between them.

Bob
 
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Bob Brines said:
95% of the battle is getting decent speakers. Amps and cables and all the rest of the accoutrements that audiophiles spend big bucks on make up the other 5%. While any two amps will be voiced slightly differently, amps have become a commodity. There isn't a dime's difference between them.

I'll have to respectfully disagree.

At the diyFEST just past, we listened to a lot of really good speakers... and we were sitting in listening area number 3 on the back deck, and the conversation came around to personal taste in speakers, and we ended up again agreeing that in a system where everything is important, the speaker is the least important. True it is the most diverse performer of the crew, and the one subject to the most personal stamp, but the rest of the kit is even more critical, and the synergy between the amp & the speaker is a "component" in itself.

If you truly believe the above Bob, you are missing a lot of the music.

dave
 
http://www.zillaspeak.com/recycledsystem.asp

My cheap ($150) Yamaha 5.1 channel receiver is just fine. I will not spend more for a receiver. The sound is fine with Tangband drivers. I think it’s a good match actually.

The Rega Brio is a bit grainy compared to the SI amp… I refuse to compare the SI amp to my tubed Cary tho… which sounds wonderful with Fostex drivers.

My old (and sold… heavy and big) Aragon SS amp sounded fatiguing with Dynaudio drivers. Overall a poor match. IMO, once heard, the shortcomings (or personal preference) of an amp make it difficult to listen to. The Dyns sounded much better with the Cary amp. Just my opinion.
 
gee Bob, have you been fitted for a flak jacket recently?; this could get very "interesting" (in the Chinese curse sense)
:hot:



Willful underestimation or outright denial of synergy (or lack thereof) in audio system matching is to say the least, a disservice to the newcomer to DIY still not unbrainwashed from the mainstream commodity market mentality you describe.

It also suggests limited experience or discernment; and at the worst closemindedness.

FWIW, count me amongst the subjectivist crowd: as smart as we like to think we are, there are many more things going on in the production and reproduction of music than we currently (perhaps ever will) have the technology to completely "understand" (i.e. measure, analyze and reduce to finite quantification).

and finally, in a well matched and musically engaging audio system, the loudspeaker could very well be the least important link in the chain.
 
I also like to think that the speaker is the most important component. The task of a speaker is rather complicated, converting an AC signal into vocals and music! I think it is quite remarkable from an electrical point of view.

On the other hand, a power amp takes a high level signal and makes it bigger. Very simple from an electrical perspective. I personally put more empahsis on the source and low level amplifier (pre amp) over the power amp.

This is not to say that the power amp is not important. Highly damped amps (typically tubes) can sound great with full-range speakers, but are often very sensitive impedance swings.

Cheers,
Gio.
 
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GG said:
This is not to say that the power amp is not important. Highly damped amps (typically tubes) can sound great with full-range speakers, but are often very sensitive impedance swings.

Amps often produce distortion which is foreign to nature so is picked up at VERY low levels. Speakers produce distortions that are much more natural and can have orders of magnitude more distortion than an amp and not draw attention to themselves.

And source -- if you don't get the info off the disk you don't hear it.

High damping amps (low output impedance/voltage amps) are fairly immune to impedance, low damping factor amps (high output impedance/current amps) are sensitive to impedance. This works out with a lot of FRs since the amp puts out more power as the impedance rises -- right where a FR needs the boost at the top & biottom.

dave
 
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