Although I am itching to build a pair of speakers from scratch, I thought I would do this mod that I've been meaning to do to my Epos' for now.
I'm about to order a pair of 2R2 5W Kiwame resistors to add to the crossovers in my M12i to tame the tweeter as was recommend to me by Epos.
However the shipping on hificollective.co.uk comes to more than the cost of the parts so thought I'd add a pair of quality caps to the order.
The caps in the speakers are 2.2uf 160VAC 250VDC.
The Mundorf MCap MKP 2.2uf are rated as 250VDC but it does not show an AC rating. I would assume these would be fine but thought I would check before I ruin something... are these ok?
I'm about to order a pair of 2R2 5W Kiwame resistors to add to the crossovers in my M12i to tame the tweeter as was recommend to me by Epos.
However the shipping on hificollective.co.uk comes to more than the cost of the parts so thought I'd add a pair of quality caps to the order.
The caps in the speakers are 2.2uf 160VAC 250VDC.
The Mundorf MCap MKP 2.2uf are rated as 250VDC but it does not show an AC rating. I would assume these would be fine but thought I would check before I ruin something... are these ok?
Would the capacitor that makes up the crossover in the speaker (the only component) be in series with the tweeter on the + or - side?
I've been told to put the resistor in series with the cap "before" it. I assume I could just put it in place of one of the external binding post links in either the + or - side?
I'm guessing they would fit the cap in the + side so put the resistor in between the + posts?
I've been told to put the resistor in series with the cap "before" it. I assume I could just put it in place of one of the external binding post links in either the + or - side?
I'm guessing they would fit the cap in the + side so put the resistor in between the + posts?
Well, I guess a silly question deserves a sealy answer from my part...
This speaker should be in phase as from a first order cap for the tweeter so check if your woofer + is connected to the + at the binding post, just to make sure. Then just connect the cap from input + to the tweeter +.
Does that answer your question?
Epos M12i Crossover Help! Why?
Hello There,
I have bought EPOSM12i just yesterday, there offered on a sale price, I'm confused here... and need helps? what the EPOS advised you to change and for what reason? taming the twitter means are you toning down its harshness?
I read that the M12i (i= Improved version) where some one said that they have modified the crossovers to tame down the harshness of the speakers already?
is that not so? please let me know as the details also as it would be a great helps for me, and I can ship the parts even though they are expensive for shipping, as I have shipped the speakers without listening... now I'm starting to get worried.
Best
TD
Hello There,
I have bought EPOSM12i just yesterday, there offered on a sale price, I'm confused here... and need helps? what the EPOS advised you to change and for what reason? taming the twitter means are you toning down its harshness?
I read that the M12i (i= Improved version) where some one said that they have modified the crossovers to tame down the harshness of the speakers already?
is that not so? please let me know as the details also as it would be a great helps for me, and I can ship the parts even though they are expensive for shipping, as I have shipped the speakers without listening... now I'm starting to get worried.
Best
TD
Hello There,
I have bought EPOSM12i just yesterday, there were offered on a sale price, I'm confused here... and need help? what the EPOS advised you to change and for what reason? taming the twitter means are you toning down its harshness?
I read that the M12i (i= Improved version) where some one said that they have modified the crossovers to tame down the harshness of the speakers already?
is that not so? please let me know as the details, as it would be a great helps for me, and I can ship the parts even though they are expensive shipping cost, as I have shipped the speakers without listening... now I'm starting to get worried.
Best
TD
I have bought EPOSM12i just yesterday, there were offered on a sale price, I'm confused here... and need help? what the EPOS advised you to change and for what reason? taming the twitter means are you toning down its harshness?
I read that the M12i (i= Improved version) where some one said that they have modified the crossovers to tame down the harshness of the speakers already?
is that not so? please let me know as the details, as it would be a great helps for me, and I can ship the parts even though they are expensive shipping cost, as I have shipped the speakers without listening... now I'm starting to get worried.
Best
TD
Your speakers are an ideal chance to build a proper XO filter from
the scratch. Exchanging a single cap and adding a 2,2 ohm resistor
will do you some good to gain experience, but won't make your itch
go away. You would have to do some studying before any serious attempt
to build a sensible filter. It is easier than many would presume.
I read up last night an introduction to crossover design and yeah it seems pretty logical for simple hi pass and low pass filters with 6dB/octave slope.
I was thinking I could add a low pass to the woofer as it hasn't got one.
But then again I would rather put the effort into shiny new speakers.
I was thinking I could add a low pass to the woofer as it hasn't got one.
But then again I would rather put the effort into shiny new speakers.
The Epos has a design that doesn't really need a bass filter.
It probably depends how good your ears and experience are with these sort of mods.
A harsh metal tweeter will probably most benefit from a Zobel at the top end.
An overly bright tweeter will need a little attenuation.
A single 2.2R resistor will only really reduce the very top end, rather like the Zobel.
Using both resistors and a Zobel will probably do too much, and take the tweeter down 4dB.
But what you may be hearing by way of harshness may be breakup coming from the bass unit. It's tricky.
It probably depends how good your ears and experience are with these sort of mods.
A harsh metal tweeter will probably most benefit from a Zobel at the top end.
An overly bright tweeter will need a little attenuation.
A single 2.2R resistor will only really reduce the very top end, rather like the Zobel.
Using both resistors and a Zobel will probably do too much, and take the tweeter down 4dB.
But what you may be hearing by way of harshness may be breakup coming from the bass unit. It's tricky.
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The 2R2 I have fitted goes before the 2.2uf cap where I have fitted it. Does it make a difference?
The additional 22.0 ohm resistor would make an L pad wouldn't it? Does it matter that network is fitted before or after the cap?
Also the resistors I ordered were metal film 5w, not wirewound. Is that ok?
The additional 22.0 ohm resistor would make an L pad wouldn't it? Does it matter that network is fitted before or after the cap?
Also the resistors I ordered were metal film 5w, not wirewound. Is that ok?
There's a very interesting interview at Stereophile with Robin Marshall, who designed the original Epos speaker.
Robin Marshall: A Modicum of Genius | Stereophile.com
I have a pair of his speakers, the MA R300-MD, from when he was with Monitor Audio. A very competent designer, and very cost effective, which is why he was so successful.
Robin Marshall: A Modicum of Genius | Stereophile.com
I have a pair of his speakers, the MA R300-MD, from when he was with Monitor Audio. A very competent designer, and very cost effective, which is why he was so successful.
I've taken it upon myself to rewire the speakers with some very good quality pure copper speaker cable while I'm on with the crossover mod. Wish I hadn't started now! [emoji1]
I've had to order a new soldering iron because mine hottest is only a 30w one and the binding posts are sucking all the heat out of it!
I've had to order a new soldering iron because mine hottest is only a 30w one and the binding posts are sucking all the heat out of it!
30W soldering irons don't really hack it with new EU approved higher temperature lead-free solder. 40W minimum I'd say. I miss the flux too, which made for good joints. But at least you're not risking brain damage from lead, and you can throw the residue in the bin with a clear conscience.
I'll give you a good intro. When first using a fresh tip, coat it with solder as it first warms up. Otherwise the tip oxidises and renders the tip useless. Gone are the days of copper tips that you simply filed down to get fresh metal. They are made of steel these days, and if you leave it hot for a couple of hours, you might as well buy a new one.
The Epos has a very nice woofer with a natural rolloff, but I'm unconvinced a first order metal tweeter filter is really the best match. But I don't have one to play with. But welcome to our hobby.
I'll give you a good intro. When first using a fresh tip, coat it with solder as it first warms up. Otherwise the tip oxidises and renders the tip useless. Gone are the days of copper tips that you simply filed down to get fresh metal. They are made of steel these days, and if you leave it hot for a couple of hours, you might as well buy a new one.
The Epos has a very nice woofer with a natural rolloff, but I'm unconvinced a first order metal tweeter filter is really the best match. But I don't have one to play with. But welcome to our hobby.
I ordered an 80w one. Might be a bit excessive but its only a cheap Antex one.
Yes I found that with the tips in the past! I'll try your advice and hopefully this one won't blacken out.
I have done a fair bit of soldering and basic electronic work before - following schematics etc. Never designed as I have only a basic grounding really. Only audio stuff I have ever done has been making up instrument cables/ fixed an fx pedal.
I do have a fair bit of leaded solder. A couple of kg maybe. [emoji1]
Yes I found that with the tips in the past! I'll try your advice and hopefully this one won't blacken out.
I have done a fair bit of soldering and basic electronic work before - following schematics etc. Never designed as I have only a basic grounding really. Only audio stuff I have ever done has been making up instrument cables/ fixed an fx pedal.
I do have a fair bit of leaded solder. A couple of kg maybe. [emoji1]
I dug up the frequency response of the similar Epos M12.2 here.
I think my comments still apply. From what I am reading, the tweeter gets a 2.2R resistor in later versions to tame the top end.
The Zobel is guesswork and I calculated it with a typical 6 ohms DC and 0.05mH. I see the tweeter is actually 5 ohms DC from the review. You should measure it with a simple multimeter. But you won't break anything with the values I gave.
Impedance Equalization (L-Pad) Circuit Designer / Calculator
I think my comments still apply. From what I am reading, the tweeter gets a 2.2R resistor in later versions to tame the top end.
The Zobel is guesswork and I calculated it with a typical 6 ohms DC and 0.05mH. I see the tweeter is actually 5 ohms DC from the review. You should measure it with a simple multimeter. But you won't break anything with the values I gave.
Impedance Equalization (L-Pad) Circuit Designer / Calculator
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