Need help finding High Pass Filter Cap

CormacBass · #1 09-08-2011, 09:03 AM

I'm looking for a high pass filter cap to put in a cabinet with two 10" speakers. The cab is rated at 8 Ohms and will have to deal with 300 watts of power.
I live in Ireland so an online store that delivers here would be perfect.

I'd ideally like the high pass to be at around 200hz

I've been searching for two weeks now but I'm drawing a blank, any help would be greatly appreciated.

will33 · #2 09-08-2011, 09:13 AM

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bongomania · #3 09-08-2011, 09:19 AM

Try these guys--they should be able to advise you on which specific parts you'll need, and they're in the UK. FWIW I think you'll need a full crossover circuit, not just a single cap. http://www.audio-components.co.uk/st...ubcategoryid=7

rpsands · #4 09-08-2011, 09:23 AM

I'd suggest expanding on what you are trying to accomplish too. Chances are if you're high passing a bass cab at 200hz you're doing something wrong.

will33 · #5 09-08-2011, 11:37 AM

You looking to run this with a real sub or just a 15 bass cab or something?

CormacBass · #6 09-08-2011, 04:54 PM

Quote:

Originally Posted by will33

Parts-Express.com sells Speakers, Replacement Speakers, Speaker Building Parts plus HDMI Cables, Home Audio and Video, Pro Audio and Commercial Sound. We offer services for Speaker Reconing, Speaker Refoaming, Speaker Repair. Great selection of Elect

I tried these guys alright, they don't deliver to Ireland sadly.

Quote:

Originally Posted by bongomania

Try these guys--they should be able to advise you on which specific parts you'll need, and they're in the UK. FWIW I think you'll need a full crossover circuit, not just a single cap. Crossover Components - Capacitors

Thank you, I'll try them.

Quote:

Originally Posted by will33

You looking to run this with a real sub or just a 15 bass cab or something?

My current set up is a homemade 400watt amp @ 4 Ohms going into two cabinets @ 8 ohms each in parallel.
The cabs are a home made 2 x 10 and a 1 x 15.
I'm getting plenty of low end from the 15" speaker so I'd like roll off the low frequencies on the 2 x 10s.

will33 · #7 09-08-2011, 05:38 PM

Do you have a biampable bass head or crossover from a pa or something to experiment with? Borrow/rent/buy and return one. I use my PA's crossover a lot to find the sweet spot before hardwiring in a crossover. Also with 210's doing mids and highs that cab might "outrun" the 15 making it sound like you're losing bass by comparison.

Some things to think about. It makes it a lot easier to be able to adjust crossover points etc. before commiting to hard parts.

will33 · #8 09-08-2011, 05:45 PM

They don't ship to Ireland at all? With little parts like that you'd think somebody could just mail it.

walterw · #9 09-08-2011, 10:06 PM

Quote:

Originally Posted by rpsands

I'd suggest expanding on what you are trying to accomplish too. Chances are if you're high passing a bass cab at 200hz you're doing something wrong.

yeah, that sounds goofy.

just run it full-range, it'll sound louder and better.

rpsands · #10 09-08-2011, 10:28 PM

If you're getting too much bass, turn that knob down.

CormacBass · #11 09-09-2011, 05:16 AM

I was emailing John from audio components uk and received this response
"As you may know a single capacitor will form a 1st order filter when working into a particular impedance (such as an 8 ohm driver). If the capacitor is in series then it works as high pass filter i.e. it will present a low impedance to high frequencies and a high impedance to low frequencies. For a ‘corner frequency’ of 200Hz, working into an 8 ohm load you would require a 100uF capacitor. The type to use for high power audio applications is a polypropylene. In our range the most economical type to choose is the Jantzen CrossCap 100uF poly which is priced at £25.94 each including VAT."

The cap he was referring to is Cross-Cap MKP; 100uF, 400v one.

Arjank · #12 09-09-2011, 06:19 AM

A passive single cap 6dB/oct crossover will not be sufficient.
I guess the cabinet is ported, this will make it even more complicated to highpass it because the impedance will have two peaks. A closed cabinet can be crossed-over passive with 6db/oct, but you'll also need to dampen the impedance peak at the resonance frequency with an LCR network.
If you close the port and add an LCR to the cross-over network, a -6dB point at 200hz will give the 10's a bit more headroom before they hit xmax.
If you have the TSP's of the 10's and you know the cabs volume I can design a network for you that could actually work.

Matthijs · #13 09-09-2011, 06:26 AM

As you are maybe looking for just a slight decrease of bass, you can try just sealing up the 2*10 box by stuffing the port. This might already be enough for what you want.

billfitzmaurice · #14 09-09-2011, 06:31 AM

Quote:

Originally Posted by Arjank

A passive single cap 6dB/oct crossover will not be sufficient.
.

Assuming the tens aren't dedicated midrange drivers a 6dB filter should be perfect. He only wants to reduce the low end from the tens, not eliminate it. Just like this guy:
Speaker configuration advice?

CormacBass · #15 09-09-2011, 06:55 AM

Sorry for the delay in responding, I'm a new member so all my posts go through a spam filter and get delayed.

@Arjank, this is not my main amp, it's my work horse. I'm currently designing a new cab based around the design of this one: Traynor Amps: Bass Extension Cabinets
The 10s are Eminence beta 10bs rated at 16ohms each
The 15 is an Eminence beta 15a rated at 8 ohms.
The power amp is a homemade mono output rated at 400 watts @ 4 ohms.

The cab will have a few modifications, I'm installing the amp on the top (it's designed as a rack mounted unit), putting large wheels and a handle on the back for easy transportation.

It's a nice little project to work on but I'm also looking for a compact combo amp that I can fit easily in the band van.

I'd like to completely redo the crossovers. The amp currently has a tweeter but I'm not sure if I'll keep it or not.

Arjank · #16 09-09-2011, 07:21 AM

Quote:

Originally Posted by billfitzmaurice

Assuming the tens aren't dedicated midrange drivers a 6dB filter should be perfect. He only wants to reduce the low end from the tens, not eliminate it. Just like this guy:
Speaker configuration advice?

If you read my post thoroughly you'll see that I write that a passive SINGLE CAP 6db/oct will not be sufficient. This is because of the fact that if you don't flatten the impedance at the resonance frequency the single cap network will not do it's job the way it's intended to be. A single cap in conjunction with an LCR will do the trick (with a closed cabinet)

staindbass · #17 09-09-2011, 07:33 AM

i have seen lots of speakers with just a cap, they designed them wrong? or is that just for woofers? here is a calculator that says a 99 uf cap would work.Speaker Crossover Calculators by V-Cap

CormacBass · #18 09-09-2011, 08:02 AM

Sorry I just check the speakers again,
they are 2 x eminence delta 10a @ 16ohms
1 x eminence delta 15lfa @ 8ohms

Arjank · #19 09-09-2011, 08:03 AM

Quote:

Originally Posted by staindbass

i have seen lots of speakers with just a cap, they designed them wrong? or is that just for woofers? here is a calculator that says a 99 uf cap would work.Speaker Crossover Calculators by V-Cap

It's wrong for all speakers with an impedance peak thats is in the working range of the capacitor.

Arjank · #20 09-09-2011, 08:04 AM

Quote:

Originally Posted by CormacBass

Sorry I just check the speakers again,
they are 2 x eminence delta 10a @ 16ohms
1 x eminence delta 15lfa @ 8ohms

I guess you run the delta 10's parallel, what's the volume of the cabinet they are in?