Xover Calculation

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I can roughly understand how this crossover works while design looks a bit unusual found inside a Chinese pro speaker that actually sounds extremely sweet

Can somebody take a look at it make some calculation and share his opinion ?

I am not realy familiar with xover calculators

Thanks
Sakis
 

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Hi Sakis. You are no fool with electronics, I can tell from your website.

Lovely old Pioneer SA 8500 II Amp on display, which I have heard, and an impressive Rotel power amp which I can dream about. 😀

The circuit is as Boswald says. A 4 ohm near 12dB/octave bass circuit and a 8 ohm 18dB/octave tweeter by the look of it. It works reasonably well with a regular 4 ohm 170mm bass in 20L box and 25mm 6 ohm 91dB tweeter.

The red resistors are a bit weird really. It works better without them in my sim with those two drivers. The dotted line when you skip them.

For those of us who enjoy building loudspeakers, one of the useful tools is Visaton Boxsim: Software | Visaton

Import any of these .bpj files into the projekte folder, and you have a quick start for some simulation: Boxsim Projektdatenbank

Naturally these projects are Visaton driver oriented, but actually often work with other typical drivers. We speaker people use measured FRD (frequency and phase response) and ZMA (impedance) files when we can get them for other brands. Boxsim can import them.

Portsmouth is like a Greek Island this week, so everybody happy. Tell us if there is a problem with these speakers. Usually easy to fix. 🙂
 

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Hi Sakis.These resistors are changing the slope of the FR ,creating a mild depression between 1kHz-5kHz.To many people a ruler flat responce in this era makes the speaker's sound somewhat oppressive.It looks like you are one of them!
 
...To many people a ruler flat responce in this era makes the speaker's sound somewhat oppressive...

No need to correct that, except for spelling with response, otherwise it works for me!

I have heard of what Paul Carmody calls the "flying squirrel", which jumps a gap in the midrange and is forgiving of terrible music recordings. Other people called it the BBC dip. But since we have NO IDEA what the speaker drivers are, everything is speculative. It is conceivable they have some awkward peaky driver response. Why the secrecy, Sakis? 🙂
 
Well in the first place i though that the resistors are there if the speaker is over powered to prevent coils from burning or share some current there

Still in the specific xover material used looks very good and beefy also so i cant be sure about that

Indeed the speaker sounds a bit edgy .... that will mean that there should be a bit of mid and upper mid less ....But that is just a bit so resitors might have something to do with this

No problems with that .... house music is in order so middle is not really our favorite area

Pushed the speakers last weekend up to 300W of clean power worked like a charm ...

Thank you all
 
The resistors are decreasing the slope of the rolloff, that's all.
Basically, the series components set the start, and the parallel components the rate of the rolloff.
They will slightly raise levels in the crossover region, apparently not needed with the drivers Steve simmed. But you can get the idea.
 
There are three Englishmen on a train. One of them is an economist, and one of them is a logician, and the other is a mathematician.

They have just crossed the border into Scotland (I don't know why they are going to Scotland...) and they see a brown cow standing in a field from the window of the train.

And the economist says, 'Look, the cows in Scotland are brown.'

And the logician says, 'No. There are cows in Scotland, of which at least one is brown.'

And the mathematician says, 'No. There is at least one cow in Scotland, of which one side appears to be brown.'

Marvellous. 😀

Don't get me onto the story of the deceased Engineer who arrives in Hell due to some administrative mistake by St. Peter at the Pearly Gates of Heaven. But it's funny as Hell, and the punchline involves Satan's own spawn, Lawyers. 😱

I conclude thus: There exists somewhere in Greece a loudspeaker. With a crossover. It's quite loud at 300W. 🙂

If you really twist my arm, I'll tell you the joke about the engineer in Hell. You won't regret it, though it might get lost in translation into Greek.
 
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