| JandG |
| 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. |
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| Jeb-D. |
| Was your sub in phase with the bass coming out of the ports? |
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| JandG |
| 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... |
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| Scottmoose |
| 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. |
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| GG |
| quote: | Originally posted by JandG
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. |
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| Bob Brines |
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 |
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| chrisb |
| quote: | Originally posted by Bob Brines
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 |
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| Bob Brines |
| quote: | Originally posted by chrisb
Bob:
did you perhaps mean "now free to go OB"? |
oops. Yes I did. And how can I edit the original post?
Bob |
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| JandG |
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 |
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| Scottmoose |
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. |
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| JandG |
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 |
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| VadimB |
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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| planet10 |
| quote: | Originally posted by Scottmoose
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 |
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| planet10 |
| quote: | Originally posted by Bob Brines
You will get even better result by using an HT receiver |
If you can find an HT receiver that you can actually listen to...
dave |
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| Bob Brines |
| quote: | Originally posted by planet10
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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| planet10 |
| quote: | Originally posted by Bob Brines
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 |
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| Godzilla |
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. |
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| chrisb |
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. |
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| GG |
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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| planet10 |
| quote: | Originally posted by GG
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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| JandG |
I thank Bob for the info on alot I am just learning, but I am no stranger to good tube amps or SS real class A jobs,,, have'nt took the plundge on these so called wonder chip amps yet or whatever they are, but the quad of 300B I run in main is a main ingredient in my sound...I actually don't own any SS amps other than 1 old jvc for testing mods & such.....there is not many ss amps in the world that will touch my midrange candy of the 300b pp amp I run,,,....I do however enjoy running Class D plate active subs in stereo pairs, on the bottom end & relieving my tube amps of lower end duty & let them sing..I will study & persue this route for a long time with full rangers, I am hooked on them BIGTIME....for SS yamaha had some GREAT amps,,, I had a MX2000, that was crazy good, but can't hang with my tube amps in the midrange.. I bought my mother a old SS Onkyo reciever that she loves, it does sound good for SS, ..& nice build quality for sure..Thanks for all the help to everyone here.
J & G |
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| VadimB |
JandG,
I am still very interested in your experience. Since nobody answered my concerns about excursion limitation, would you, please, answer some of my questions:
1. What is the volume of your cabinets for FE167? What is the ports size?
2. Can you describe more precisely how did you plug the ports? I am tryimg to gage to what degree it is totally plugged, or became an aperiodic box. I actually like aperiodics a lot, but they are not easy to simulate or predict. Experimentation with those is a must.
3. How much power do you think you are driving them with on average? Is there any hint of bottoming out the suspension? To check on this, you may want to drive your system with some well known to you recording to fairly loud level and then shut off the subwoofers. At this point any problems with low end of Fostexes should becoume audible.
I am very interested in making a new system, employing some wide range driver instead of Manger, and FE167 is certainly a candidate. Therefore your feedback would be greatly appreciated.
Vadim |
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| planet10 |
| quote: | Originally posted by VadimB
2. Can you describe more precisely how did you plug the ports? I am tryimg to gage to what degree it is totally plugged, or became an aperiodic box. I actually like aperiodics a lot, but they are not easy to simulate or predict. Experimentation with those is a must. |
I have 2 methods of designing an aperiodic box....
1/ for a high Q driver (that would probably prefer to be on an OB -- build a box as big as you can live with and then add some holes as far away from the driver as you can. Then damp the holes (i have done this by ear in the past, but the last one i did was pre impedance measuring kit)
2/ for a lower Q driver, i model a BR box with a specific shape curve (ie by feel), then make the ports with a high aspect ratio to push the box towards aperiodic. If that isn't enuff then i use fairly stiff packing foam to block the port (i end up with lots of it lying around (a specific foam from Apple Service parts boxes works well))).
Attached is the measured imp with & without the port damping... you can see the bottom hump disappearing (and is already pretty small -- indicating some aperiodicity without).
This technique worked really well for the FE127 (the Fonken) and we have an untried design for an FE167 (the Mama Fonken) and will also try the 207 (Papa Fonken) & Neophone (NeoFon-ken)
dave |
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| Scottmoose |
| You can also try simulating them in Martin King's MathCad worksheets. Edit the stuffing position to add a goodly quantity to the port you've specified. |
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| VadimB |
Dave,
According to my experience, the Z-plot you've attached is not exactly an aperiodic alignment. I've built several speakers with both Variovent (Scan-speak) and my own aperiodic damping. All of them had a single impedance peak at almost the same F as a closed box, but with lower Q. Your plot looks more like heawily damped TL or BLH. I'm not saying it can not be done this way - just that it's not the same as you'll get with Variovent. Also, in my experience, the closer to the driver you put the damping device - the more efficiently it works.
I use WinISD (Pro Alpha) to simulate aperiodic box. You should model a closed box, then click on "advanced" button in "Box" tab. It'll show the Qb (Q of the box). Default value is 10. For a well-made box of 30-40 liters that's about right. Smaller boxes will have higher Qb in real life. Then, I change Qb to about 3. Resulting plots will give you a good estimate of an aperiodic box. However, this approximation is not as close to the real thing as other "standard" models in WinISD.
I'd like to thank all, who replied. But, my concern is actually a different question.
New version of WinISD (Pro Alpha) has this very useful plot, called "Max Power". It shows "Power, required to reach Xmax vs. Frequency". I've tried the BR boxes suggested by Fostex and by Zilla. Basically, the results are the same - all these should bottom out the suspension at something like 0.5W at 100 Hz and below.
My question is - have any of you, who have FE167 (or any of the FE series for this matter) in BR or closed boxes, experienced this bottoming of the cone? How do you get around this problem? Do you limit your power to 1/2 W, do you carefully choose what kind of music to play over these speakers, or is WinISD wrong by a big margin? So far I have quite a bit of respect for this program. I've got very good match between it's models and actually built speakers.
Thanks,
Vadim |
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| VadimB |
| Here is a simulation of FE167 in 25 l box, tuned to 70 Hz: |
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| chrisb |
| quote: | Originally posted by VadimB
Dave,
New version of WinISD (Pro Alpha) has this very useful plot, called "Max Power". It shows "Power, required to reach Xmax vs. Frequency". I've tried the BR boxes suggested by Fostex and by Zilla. Basically, the results are the same - all these should bottom out the suspension at something like 0.5W at 100 Hz and below.
My question is - have any of you, who have FE167 (or any of the FE series for this matter) in BR or closed boxes, experienced this bottoming of the cone? How do you get around this problem? Do you limit your power to 1/2 W, do you carefully choose what kind of music to play over these speakers, or is WinISD wrong by a big margin? So far I have quite a bit of respect for this program. I've got very good match between it's models and actually built speakers.
Thanks,
Vadim |
I've no test equipment handy, but I can be pretty certain that some of my playing levels are well in excess of .5w - and I can never recall any of the current Fostex drivers (FE126/127/167) that we've tried in a variety of enclosure designs bottoming out. In fact the smallest tube amps (<3w) can easily be driven to clipping before any noticable distress from the drivers.
The powerful XBL motor system notwithstanding (or perhaps because of it), the CSS WR/FR125, on the other hand can exhibit some uncontrolled colonic gas emissions if driven moderately to hard in an enclosure that unloads the driver; and particularly in my experience with low DF SE tube amps. I'm pretty sure others have commented on this as well - easily mitigated when using them in an HT system with high DF SS amp stages and bass management control functions; hi-pass filter and cross them over to a powered sub anywhere from 100-120, and you're probably safe for all but insane SPL.s |
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| seanzozo |
| quote: | Originally posted by VadimB
Dave,
According to my experience, the Z-plot you've attached is not exactly an aperiodic alignment. I've built several speakers with both Variovent (Scan-speak) and my own aperiodic damping. All of them had a single impedance peak at almost the same F as a closed box, but with lower Q. Your plot looks more like heawily damped TL or BLH. I'm not saying it can not be done this way - just that it's not the same as you'll get with Variovent. Also, in my experience, the closer to the driver you put the damping device - the more efficiently it works.
I use WinISD (Pro Alpha) to simulate aperiodic box. You should model a closed box, then click on "advanced" button in "Box" tab. It'll show the Qb (Q of the box). Default value is 10. For a well-made box of 30-40 liters that's about right. Smaller boxes will have higher Qb in real life. Then, I change Qb to about 3. Resulting plots will give you a good estimate of an aperiodic box. However, this approximation is not as close to the real thing as other "standard" models in WinISD.
I'd like to thank all, who replied. But, my concern is actually a different question.
New version of WinISD (Pro Alpha) has this very useful plot, called "Max Power". It shows "Power, required to reach Xmax vs. Frequency". I've tried the BR boxes suggested by Fostex and by Zilla. Basically, the results are the same - all these should bottom out the suspension at something like 0.5W at 100 Hz and below.
My question is - have any of you, who have FE167 (or any of the FE series for this matter) in BR or closed boxes, experienced this bottoming of the cone? How do you get around this problem? Do you limit your power to 1/2 W, do you carefully choose what kind of music to play over these speakers, or is WinISD wrong by a big margin? So far I have quite a bit of respect for this program. I've got very good match between it's models and actually built speakers.
Thanks,
Vadim |
I take it you have never played with a FE-166/167. The physical x-max is an order of magnitude higher than the magnet-gap x-max (the .6mm). You won't bottom them generally (I haven't ever), you'll just get increasing distortion. I have seen displacements of +/- 1CM (SWAG) with no really ugly sounds.
Sean |
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| JandG |
| .72 cu ft. & port size is 3".... & I even stuffed port even tighter with acoustic filler. It is even better in the mids, but have to get the sub up near 150,,, but it is NOT bad........the mids are very good & will experiment this weekend somemore with it..there is no cone movement I can see now even @ fairly loud levels, I am not try to get these to do large bass duty at all, just use the midrange for what it is,,,GREAT.. I am listening to Loreena McKennitt " Live in Paris & Toronto",,, good test for any system , especially vocal.,,,I detect no shout,, & will make up my mind this weekend if I need a helper tweeter crossed high, but that is a big maybe on the tweeter. I will try what you said about stopping the subs & report back to you....The cabs they are in are MDF witha 1" baffle..& 1 internal brace in the middle..If Lorenna McKinnitt does not raise ever hair on my body on every song see sings,, on any album of hers, then I am not happy with system at all..I need this weekend to see if I can live with any trade offs I might find...should be intresting... |
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| JandG |
I must say again that I am as I write running this set up with a Canary CA301 MkII @ 22w of 300B & now have turned it up alot thru a TVC & there moving good, but no distortion detectable yet, & not moving more than I am used to seeing, nothing scary looking that is,, If it blow apart I will certanlly let you know..*s*
I have some compression plugs I bought @ my plumbing store & will test also completelly sealed, with low volume & then some...Also will let you know.. |
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| JandG |
| I installed the 3" compression plugs & also installed a helper tweeter. Pair of Vifa D27TG-45's, all I have on hand, ended up with .22uf Auricap for value..set subs @ 150 & it is all holding tight up to very loud levels without seemingly messing with the very nice midrange...Imageing seeming to be holding also,, I don't have a clue what I am doing,,, but am having fun.. ,,, so all I got is my ear & some help from others. I truely see my self soon going B200 in OB w/ my pair of subs & LCY-100K's on top set very high....I think this would make me very happy, If a/b on the LCY-100K's don't seem needed, I can sell them,, I have a sets of differant tweeters & style on the way to try ifferant things before spending big $ on the keepers..I am sure I am about to blow something up,... Fostex, amp...etc. *s* |
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| JandG |
| Pulled the plug in fe167e's, pulled the stands, mounted monitors directly on top of front fire subs, changed cap to .0056uf styrene. Slightly stuufed the port in subs.. set @ about 70 integration is HECK of alot better, will work with rest...hated to see my stands go to spare room, but they will stay there for now. Didn't even relise integration was that far off....oh well..It is creepy good now, Can't wait to try ribbon's, horns, etc, @ 94db & go from there.....Why is this soft dome doing so well..? @ 90db I think |
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| JandG |
pulled all suffing from fe167e cab's. Put compression plug BACK in port.. kept subs slightly stuffed & went back to 150hz with them...
.0056uf styrene cap on the Vifa D27TG-45-06..seems like a good value finally..must be WAY up there, but works for me..the fostex imaging & mids seem presevered, which is what I want..I do like it better without the white fiberglass that was in upper cabs..also integration is MUCH better with monitors directly on top & flush with sub front's..I think I need to get the set up on granite like I had my stands on...I will try it.. |
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| JandG |
Picture of the funky set up.. |
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| GG |
| quote: | Originally posted by chrisb
I've no test equipment handy, but I can be pretty certain that some of my playing levels are well in excess of .5w - and I can never recall any of the current Fostex drivers (FE126/127/167) that we've tried in a variety of enclosure designs bottoming out. In fact the smallest tube amps (<3w) can easily be driven to clipping before any noticable distress from the drivers.
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Keep in mind that the WinISD sim represents continuous power at a fixed (low) frequency. Music typically does not do this.
Mine seem to take about 4W of soft rock before they start to color the sound. However, some bass intensive music can sound ugly with as little as 1W. So it is music dependent.
If you limit the bass to these drivers, you can get some serious SPL. |
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| JandG |
may I ask how you make a simple circuit for cutting the bass off @ 150hz, I would love to be able to do that,,If i can I think I will be amazed.....I would appreciate the help.
Thanks,
J & G |
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| VadimB |
Thanks again for all the replies.
Sean, you are right: I have not tried them yet, exactly because I could not see how to get a reasonable SPL before bumping into Xmax. However, after spending 2 years to make Manger sound right, I am more than interested to try something else, especially since anything else is significantly less expensive.
JangG,
the easiest way to limit bass in your set-up is to put a cap in series with the input of power amp feeding the Fostex. This would create a first order RC crossower. It's the same formula as you use for the supertweeter, but instead of the impedance of the tweeter sustitute the input impedance of the amp (usually between 10 and 100 kOhm). I don't remember the formula over the top of my head now, but it should be in the range of .1 - 1 uF. If you can't find the formula, let me know and I'll dig it out.
Also, I have tried a bunch of supertweeters for the Manger and settled down on LCY -100K that you've mentioned. It's the only one that did not screw-up the imaging of the Mangers. Mangers do disappear completelely. Any other tweeter I've tried, regardless of how high crossed, would give out it's location. I have to pad LCY down with 2 Ohm series resistor and use higher setting of the crossower to match the Manger. I would guess, that with Fostex you may get away without padding. Good luck!
Vadim |
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| JandG |
If you run into the formula it would help me alot,,, I did NOT use a formula for tweeter, just started with 2uf & went by ear from there, took 2 days.................LOL...If you can't find it , I'll get it by ear,, the starting point you gave me is of GREAT help.....Thanks so much.. also that is great news on the LCY -100k, .....
J & G |
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| VadimB |
| quote: | | If you run into the formula it would help me alot,,, |
Here it is:
C=1/(2*Pi*Fxo*Rin),
where:
C- capacitance of the cap, Farad
Pi = 2.14...
Fxo - crossover friquency, Hz
Rin - input impedance of the amp, Ohm
Note: uF=E-6 Farad
For 150 Hz and 10k input impedance C=0.1uF
For 150 Hz and 50k input impedance C=0.021uF
For 150 Hz and 100k input impedance C=0.011uF
Keep in mind that you will get only !st order electrical Xo. However, FE167 in your box has acoustical 2nd order high-pass at -6db point of about 85-90 Hz, so the resulting accoustical Xo would be close to 3d order. What Xo do you have in the sub amp?
To get away from all of this, I am using Marchand XM9 active Xo, 4th order.
Also, as mentioned in previous post, good phase match is extremely important at these friquencies. I have continuous phase adjustment built-in in the sub amp. If you decide to take the plunge and go active Xo, Marchand offers an optional phase adjustment circuit on his active crossovers. BTW, I can highly recommend his products.
Vadim |
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| VadimB |
Sorry, it's getting late:
Pi is approximatelly 3.14.., not 2.14 as I've mistyped.
Vadim |
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| JandG |
They are my 1st subs, suposed class D active with 50-150 setting, & also level adjustments, also phase 180-0 adjustments, I use the high pass in... do you think I can still try to cut it off @150 even with the wizzer still attached. I have Dave's phase plugs intalled & love those..... but wizzer is still attached & also remeber my cabs are now SEALED, don't know if that matters on cutting them, but sounds much better as a whole so far..Thanks for all the help in this.
J & G |
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| JandG |
When I did the example of 150hz & 100K input impedance I came up with 0.000000011 instead of .011 ? Does the Note: uf =E-6 Farad have anything to do with it, I am not good at math but my daughter can help...If I new WHY decimal was moved 6 spots then I could get this...
Thanks,
J & G |
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| planet10 |
| quote: | Originally posted by JandG
I came up with 0.000000011 instead of .011 ? Does the Note: uf =E-6 Farad |
0.000000011 = 0.011 E-6 Farad = 0.011 microFarad
dave |
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| ronc |
I have three amps at present and they each have their positives and negatives.
Yahama HT. sounds good overall, but lacks definition.
Battery powered LM3875 gainclone. the most detail and a freaky blackhole background but with 5 watts/channel it takes a very efficent horn system to get the bass right.
SET. with only 2 watts a channel there is a problem with real bass even with efficent horn loading, but has a fanstastic mid response and the best soundstage of the three.
The most used for music is the GC, but i play movies with the HT system. The set mainly mass loads a shelve in the closet.
ron |
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| planet10 |
What is the SET? EL84? 45?
dave |
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