Capacitors purchased

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Hi i am out buying caps right now so i dont have a camera but the ones i have so far tracked down are these giant yellow Bennics .. if i remember correctly these are FAR superior to electrolytics for passive correct ?

also found truly huge black caps with red ends that say PXA22QY75T 22uF 75VAC

all of these are omni polar and i am thinking they are all film or polypropolene. I am really close to buying these oil filled jobs but they are stupid big . I will post a pic of these when i get home BEFORE i use them so if i screwed up i can return them.
 
Hi i am out buying caps right now so i dont have a camera but the ones i have so far tracked down are these giant yellow Bennics .. if i remember correctly these are FAR superior to electrolytics for passive correct ?
For passive crossovers any cap that isn't an electrolytic is FAR superior :). The Bennic caps you speak of I believe are polyester, and are quite good. Not quite as good as Solen Fast Caps (polypropelyne), but they are also cheaper.

I think for the best price/performance ratio polypropelyne caps are the best bet.
 
Ok here is a bad photo of the caps i bought a whole whack of them in various values. Are these poly or metalized mylar something or others ?

I didnt buy the oil caps although i am sure they would have been fun they are just too damn big. mini flask size :xeye:

Are these good ?
 

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WOW ! ! !

I just built the left side x-over with those other caps i purchased in the picture above. I kept the electrolytics in the right side. Then i played music. Fading left to right was a revelation. You would have to be deaf not hear the difference. It appears to be a wide open unmuffled midrange.

Does this jive with anyone else experiences with proper caps ? :bigeyes:
 
The yellow Bennic caps in your picture are polyester ones I thought they were. I have a couple of them in my own crossovers because of the large size I needed the Solen caps were a little expensive.

Like I've already said, anything that isn't electrolytic is far better. Quite a bit more expensive too but it's worth it as I'm sure you know now. Just another note about choosing crossover components, never use an iron core inductor. Always air core. I don't know about any other manufacturers, but Solen provides the series resistance spec for all of their inductors so you can take all factors into account when designing the crossover.
 
At this point in time i dont have a choice but to use the IRon core as i havent had time to finish building my winding 'kit' I am sure there is something off with the iron core because they saturate and a few other undesirable characteristics. But until i hear them differently i will have to get by with it.



COme to think of it, they might be why i cant get a nice smooth mid sound :mad:
 
Iron core will always outperform an air core, if it is designed to handle the required power. There are good iron core coils available, such as the Erse devices. At H.E.L. we always prefer Erse iron cores to any air core in woofer circuits, if the right value is available. The lower DC resistance is always welcome. The Erse units we use are rated for 500 watts, which should be enough for almost any application. We have found that the 500 watt rating is quite conservative, as we have seen no core saturation even at 1000 watts in our bench testing. We use air core coils in our midrange and tweeter circuits, where the increased Dc resistance isnt a problem, since attenuation is usually required for these circuits anyway.
The blanket recommendation to always avoid iron core coils makes no sense. We do recommend avoiding ferrite core devices, unless there is good data on power handling, since cheap iron core (ferrite) often have no reliable data. Stay with the better iron core devices, using laminated cores for your woofer circuits.
 
Ahhhhhh i asked but no one answered me when i wanted to know if it was frequency or power that saturated it. Now i know. I am no where near that power level so i dont have to worry ? Also these are not cheap iron cores, they are steel/iron whatever wafer cores.
 
Be very careful about using the "make a change to one speaker, leave the other one the same, use stereo source material and fade between the two speakers to hear the difference" method of testing a modification. In lots of source material (Miles Davis "Kind of Blue" for example) the left and right channels have the same instruments being played, but they sound very very different. This can lead to false positives or negatives.
 
FOund this on one of those educational web sites

" In a sense, crossovers are the brains of the loudspeaker system. They are designed to optimize driver performance and assure proper blending of the drivers enclosed in the speaker system. The quality of the components used in the filter system have a direct impact on the fidelity of sound which can be achieved. Polypropylene capacitors are preferred over Mylar's due to their low ESR (effective series resistance) and tighter tolerances. In addition ceramic resistors are preferred since they have high power handling and low DCR (DC series resistance). Air core inductors are preferred over iron core for the following reasons:

Eddy Currents: When inductance is applied to an iron core, voltage is induced in the core. The eddy current flows in opposite direction to the coil flux, which results in power loss and increased distortion. Eddy currents are negligible in air cores because voltage isn't induced in a non-magnetic core.

Hystereses Losses: Magnetism is induced in an iron core when voltage is applied to it, magnetizing the core in one direction. Additional power is needed to reverse the magnetic field, and the reversal may not be instantaneous resulting in unwanted distortion. Therefore, air cores have substantially reduced Hystereses distortion due to the fact that they have no magnetic core. It should be noted that Hystereses becomes greater at higher frequencies since the frequency changes much more rapidly , in excess of 20,000 times per second (20KHz).

Saturation: Induction decreases when more power is applied. The reason for this inverse relation is when all the magnetic lines of induction become full, or saturated, only a small additional amount of induction can be produced which leads to distortion. Iron cores often become saturated 2 or 3 times faster than air core inductors.

In general, air core inductors with the largest practical diameter wire are always the preferred parts to use in cross-over design providing that they are within size constraints (larger values result in larger parts) of the cabinet and meet the budget constraints of the speaker system.

Filter slopes and topologies are a function of the drivers employed, positioning of the front baffle in relation to the drivers and budgetary constraints of the system. The main importance of the filter network is to ensure as close to flat frequency response over the entire audible spectrum as possible, to present the amplifier with a controlled input impedance, and to optimize driver performance by electrically limiting each driver to produce the frequency band it is designed for. "


I think ill take that as the gospel truth and get air core soonest if i dont get my DCX anytime soon.
 
All of those issues are real, but can be designed around. I still say that a properly designed iron core is superior for woofer circuits. Unfounded fear of iron core inductors costs too many people amplifier power and loss of damping.
Of course, the best way to crossover is actively. The best crossover is no crossover. Bi-amping is crucial if you really want a state of the art system, but if you must do it passively, use the best components for the job. Good iron cores for the bass.
Using the Erse units I mentioned earlier, which are designed for 500 watts, you need not fear them, especially if you are using less than a couple of hundred watts per channel. Most people are using much less than that. If you are using low power SET amps, you will be hard pressed to even saturate a small poorly designed ferrite core inductor (not that I recommend ferrite core, which I dont).
 
I have tried everything out there and I even use the Erse super Q inductors in a three-way design we offer.

Iron core inductors have there place in low bass circuits but I would never use an iron core inductor in anything playing over 150 to 200Hz, and never in a two way design.

Any air core inductor will sound MUCH better.
 
To Danny...

since you're already in this thread on capacitors, i was wondering
if theres possibilty to get sonicap to make a 130 or 150uF for
those latest polyprops version.

I've always wanted to try out sonicaps for my existing 5 satellites
which currently uses a single Mundorf MCAP 150uF on the mids
before onto the XO.

Maybe Sonicap Poly coupled by the smaller Teflon just to improved the highs a bit.What would you suggest?
 
I am guessing that those large values are in the woofer circuit. Sounds like part of a high pass filter in the woofer circuit.

I'd use the Mundorf but by-pass them with a Sonicap that is about 10% of the Mundorf value. Yes, you'll have to use a smaller mundorf cap. Then by-pass that with a .1uF Sonicap Generation 2 by-pass cap.

Inexpensive but effective.
 
Okay.But since i'm out to try sonicap, i'd rather have them both
as the main cap and the bypassing cap.

130uF + 15 to 20uF ? Will it be possible for sonicap to produce
such a size? So far i've only came across Solen and Mundorf
that has 130uF & 150uF polys.

If i were to use the existing Mundorf then 10% value for the bypassing cap i will end having say 165-170uF.
Means there'll be lesser midbass for them satellites. :xeye:
 
Okay.But since i'm out to try sonicap, i'd rather have them both

The reason I recommended what I did is because the Sonicaps are only made as large as 30uF and they are pretty big at that.

I don't see them making them any larger anytime soon.

If i were to use the existing Mundorf then 10% value for the bypassing cap i will end having say 165-170uF.

Check Mundorf values as well as Axon and Solen for the large values.

We only stock Axon up to 62uF but I do have a few 75's and 100's laying around.

Sonicap values can be seen on our web site.

Figure out a way to get a combo to reach your values. You can use larger percentages of Sonicaps as well. The 10% value I gave you is a minimum.
 
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