Home » Audio » Speaker » fostex design search results
Adding some passive components to a speaker [message #20443 is a reply to message #20438] Thu, 23 September 2004 08:54 Go to previous messageGo to next message
akhilesh is currently offline  akhilesh
Messages: 1275
Registered: May 2009
Illuminati (3rd Degree)
HI John & Others,
I can offer my insights, based on personal epxerience, as well as some reading. IMHO, adding a few passive components makes no difference audibly. Also, from a mental experiemnt standpoint, adding one resistor and an inductor to a circuit should not really make it less predictable.

In fact, the way I do it is: start with the amp, then build a speaker using T/S params, and a passive netwoork, so that the speaker mates well with the amp.

I have personally followed MArtin;s advice and used a passive network, and it improved my speakers considerably, with no sonic deteriorations that I could hear. You may want to try and find scientific studies that investigate if phase shifts (without frequency shifts) are audible. My own experience tells me: no.

IMHO the major determinants of speaker AUDIBLE performance are frequency curve, distortion and efficiency (with efficiency being a distant third, provided reasonable amplification is used).
-akhilesh


Re: Right on [message #20447 is a reply to message #20440] Thu, 23 September 2004 17:52 Go to previous messageGo to next message
Oberon is currently offline  Oberon
Messages: 20
Registered: May 2009
Chancellor
===> "I simply maintain that ideally, you want this load to remain as pure as possible, especially when using amps that are sensitive to loads which are usually lower powered."

What you just said advocates the use of impedance compensating networks with loudspeakers because they make the load more pure.

===> "Why all the fuss for connecting one amp to one coil??"

There are several benefits for biamping and triamping, and most don't have anything to do with load impedance, response shaping or speaker voicing. Those are separate issues, and they shouldn't be confused as being related.

Biamping and triamping are great ideas so don't misunderstand my meaning. It isn't because the voice coil is pure though; It isn't about that. What it IS about is using rhetorical comments about "purity" where the description doesn't fit.

IMHO, YMMV and all the other usual disclaimers apply.

Re: Right on [message #20448 is a reply to message #20447] Thu, 23 September 2004 19:42 Go to previous messageGo to next message
TC is currently offline  TC
Messages: 41
Registered: May 2009
Baron
>>> "Why all the fuss for connecting one amp to one coil??"

==Every passive element adds a sonic signature period. Measurable and audible. Coil, resitor, etc.. The difference is easily heard provided the system has sufficient resolution from start to finish.

>>>There are several benefits for biamping and triamping, and most don't have anything to do with load impedance, response shaping or speaker voicing.

==Well you can look at it that way. In fact multi amping serves to mitigate the detrimental effects of all the items youv'e accumulated above.

>>>Those are separate issues, and they shouldn't be confused as being related.

==Impedance and response shaping issues and back EMF, oh my. Power compression and electric phase accuracy and arrival time. All represent the final load and circuit issues. What comes out of the cone is the culmination of all of these and more. Of course they are all interrelated.

You cannot seperate the amp circuit from the speaker in cause/effect scenarios. Amps do not sound the same, and change their sound with different loads.

I apply no desclaimers or apologies in advance for metiocre sound, my results are predictable.

TC

==



Re: Right on [message #20449 is a reply to message #20447] Thu, 23 September 2004 19:52 Go to previous messageGo to next message
TC is currently offline  TC
Messages: 41
Registered: May 2009
Baron
>>What you just said advocates the use of impedance compensating networks with loudspeakers because they make the load more pure.

==More pure eh?

Well tell me how a load becomes _more_pure_ by adding things to the circuit.

I have many 1-3 watt amps, some killowatt amps, some 15 watt amps. They all sound better with no passive elements between them and the single voice coils. I also have a shelf with dozens of mini chassis with BSC's, notcho filters (adjustable), gizmo's of all kinds tranny based and RLC based, various single driver circuitry tweaks. And on the shelf they stay. They all impede on the music.

TC

Re: Right on [message #20453 is a reply to message #20448] Thu, 23 September 2004 20:56 Go to previous messageGo to next message
Oberon is currently offline  Oberon
Messages: 20
Registered: May 2009
Chancellor
===>"Well tell me how a load becomes _more_pure_ by adding things to the circuit."

Look up conjugates.

===>"Every passive element adds a sonic signature period."

Why stop at the electronics? That's the point here. You have mechanical and acoustical elements also, and they are just as much a part of the deal.

===>"You cannot seperate the amp circuit from the speaker in cause/effect scenarios."

That's also the point. Nor can you separate the cabinet size, type, shape, horns if used, ports if used, speaker suspension, cone mass, breakup modes, etc.

===>"I have many 1-3 watt amps, some killowatt amps, some 15 watt amps. They all sound better with no passive elements between them and the single voice coils."

You think _everything_ sounds better that way? Well, you have a right to like what you like.

Lets agree to disagree on that. Our preferences may not be the same. It is not my highest goal to have the voice coil of a fullrange speaker connected directly to the output of an amplifier. It is _my_ highest goal to have a good sounding speaker system.

Take for example a high efficiency fullrange speaker with Qts=.2 on an infinite baffle. Most people will probably find it shrill. You will have to use EQ in one form or another to bring up the bass. You can use electronics or you can put the speaker in a cabinet that boosts bass. Another way to do it is with a subwoofer, and that will keep bass off the fullranger. Any of these are better than the fullranger by itself IMO.

Maybe you would be happier adding mass to the cone or removing magnet material. You might like using a back horn. You and I might agree on one of those things. I see them as possibilities but the difference between us is I don't see them as being the _only_ possibilities.

===>"I apply no desclaimers or apologies in advance for metiocre sound, my results are predictable."

That's the problem, you have made no concrete predictions. To make the general statement that any amplifier sounds better connected directly to an unspecified fullrange speaker is vague and doesn't pass muster IMHO.

Re: Right on [message #20455 is a reply to message #20453] Fri, 24 September 2004 08:34 Go to previous messageGo to next message
TC is currently offline  TC
Messages: 41
Registered: May 2009
Baron
>>I see them as possibilities but the difference between us is I don't see them as being the _only_ possibilities

== "only" possibilities is limiting. I am only interested in -optimum- solutions. You have presented only basic non ideal scenarios, "what if's". Keep up the good work.

TC

Good points Oberon [message #20457 is a reply to message #20453] Fri, 24 September 2004 23:14 Go to previous messageGo to next message
akhilesh is currently offline  akhilesh
Messages: 1275
Registered: May 2009
Illuminati (3rd Degree)
My own experiences bear out what you have said.
-akhilesh

not much you can do to save fe206 [message #20461 is a reply to message #20425] Sun, 26 September 2004 11:11 Go to previous message
kloss is currently offline  kloss
Messages: 36
Registered: May 2009
Baron
I used them in a few projects have a pair in oris 200 they do need some correction or use in front horn with none.I do not like this driver to me it sounds about what it costs.Maybe Iam jaded but why not use a better fostex in a proper cabinet and no filter? just a thought the fe206 is ok for entry level but thats about it.I do understand some folks only have cash for these but they only offer a small taste of what a proper fostex system can deliver[even when filtered],I have owned or messed with most fullrange or wide range drivers so many are better than fe206,also Bert D cabinet is designed for fx200 and f200a fe206 would be just ok in singular.Iam not the only speaker builder who thinks this.:)Hate to say it but I agree with Terry on this .lol.Just my 2 cents worth your milage may very

Previous Topic: Line array enclosure
Next Topic: Bandpass subs
Goto Forum:
  


Current Time: Wed Sep 11 17:57:15 CDT 2024

Sponsoring Organizations

DIY Audio Projects
DIY Audio Projects
OddWatt Audio
OddWatt Audio
Pi Speakers
Pi Speakers
Prosound Shootout
Prosound Shootout
Miller Audio
Miller Audio
Tubes For Amps
TubesForAmps.com

Lone Star Audiofest