FE206eN and Alpha 15 in OB?

[aquapiranha]

does anyone have experience of these drivers together in an OB? or even if it is feasable?

If OK, what freq. would you be crossing over at? 200hz?

I already have plans for the 103E and Alpha OB I was planning on building, but just wanted to canvass opinion on the other option.

Many thanks!

 

[brookbh]

I would think you would need 2 Alpha 15s to make up the difference in efficiency between the 103e and the 206en. Is this going to be passive or active, any eq?

 

[Scottmoose]

Right, unless you pad the 206 down, twin Alphas will be better. Hell, twin 15in bass drivers are always worth having anyway. Too much is good.

 

[aquapiranha]

Thanks guys. Scott, the drivers would be borrowed from the Sachiko's I built. Do you have a design for twin alpha's and a 206 in mind? I could always get some more...


Steve

 

[Scottmoose]

Not particularly, just philosophising (as I do) -when it comes to bass, the more units the better IMO. Bass is where the brute-force approach works. Should do OK on Martin's basic twin bass unit baffle; 40in x 20in, twin Alpha 15s, crossed 2nd order, low pass at 200Hz, high pass 500Hz.

 

[aquapiranha]

Thanks Scott, I take it you mean Martin J King? not sure what the crossover you talk about means fully though, guess I ned to learn!

Steve

 

[planet10]

I would think you would need 2 Alpha 15s to make up the difference in efficiency between the 103e and the 206en. Is this going to be passive or active, any eq?

If you want to XO passively and use little or no padding on the 206 you will need 4 woofers. It should kickass.

dave

 

[brookbh]

So what does the actual 1w/1m efficiency of the Alpha 15 drop down to on a flat baffle, around 90db? or even lower

 

[aquapiranha]

If you want to XO passively and use little or no padding on the 206 you will need 4 woofers. It should kickass.

dave

Dave, are you saying I would only need a filter on the bass side rather than the 206? that sounds like as you say is would rock. How would I do this for 2 bass drivers? I have a schematic for a filter for one, but not two?

So many questions I know, I really appreciate the help!

Steve

 

[planet10]

Dave, are you saying I would only need a filter on the bass side rather than the 206?

No. Just that if you want a passivce XO, and no resistor or L-Pad on the 206 you'd need 4 15s.

dave

 

[Scottmoose]

On the basis that if enough is sufficient then too much is just right, then I'd agree. That said, based on the average spec. for the 206eNs, 2 Alpha 15s should do an acceptable job on the aforementioned baffle with a 2nd order:

 

[aquapiranha]

No. Just that if you want a passivce XO, and no resistor or L-Pad on the 206 you'd need 4 15s.

dave

Thanks Dave, I would prefer not to interfere with the 206 tbh.

On the basis that if enough is sufficient then too much is just right, then I'd agree. That said, based on the average spec. for the 206eNs, 2 Alpha 15s should do an acceptable job on the aforementioned baffle with a 2nd order:

I will keep an eye out for another pair of 15's, and look into how to wire them "2nd order"

Many thanks guys, you two have always been helpful.

Steve

 

[planet10]

I would prefer not to interfere with the 206 tbh.

You are going yo over excurse it if you don't have some sort of high pass on it... least innocuous is a PLLXO built-into the amp (using appropriate coupling caps if possible)

dave

 

[aquapiranha]

You are going yo over excurse it if you don't have some sort of high pass on it... least innocuous is a PLLXO built-into the amp (using appropriate coupling caps if possible)

dave

Sorry Dave I am a noob and have no idea what that means. I was planning on driving the fostexs with my decware zen, and the bass drivers with maybe a chip amp. I know the bass will need some form filter.

 

[rjbond3rd]

Hey, I am also a newb.

* Over-excurse == cone travels too far, past the 1mm or so maximum excursion (xmax) that it's designed for. By putting the signal through a high-pass filter before it hits the FE206E, the Fostex will not bother trying to play those bass frequencies, and will more likely stay within its xmax unless you really crank it.

* PLLXO == passive line-level cross over, e.g. a circuit between the preamp and the (two) power amps, as opposed to having the circuit at the speaker's input terminals (after the power amp). I would assume the goal is to make the most of a low-powered amp's precious wattage?

You can also use (a) an ordinary crossover circuit, or (b) an active crossover, e.g. a rackmount pro audio device, or (c) in a pinch, cobble together whatever you have, e.g. there are ways to fake a crossover with a mixing board.

 

[planet10]

Sorry Dave I am a noob and have no idea what that means. I was planning on driving the fostexs with my decware zen, and the bass drivers with maybe a chip amp. I know the bass will need some form filter.

With a decware Zen you can achieve a 2nd order filter by changing the coupling caps to an appropriately smaller one and by adding a single cap (per channel) on the input.

dave

 

[rjbond3rd]

Dave, pardon my ignorance but could you explain how the signal is split at the source to feed the two amps, e.g., the Zen for the Fostex and another amp for the Alphas?

 

[aquapiranha]

With a decware Zen you can achieve a 2nd order filter by changing the coupling caps to an appropriately smaller one and by adding a single cap (per channel) on the input.

dave

Hi Dave, i would rather not modify the Decware, so I assume I would need a filter on the 206 instead. I will check out options on the filter. there is another option of course, and that is to go active with a Behringer / DBx and a couple of amps.

Steve

 

[planet10]

i would rather not modify the Decware, so I assume I would need a filter on the 206 instead. I will check out options on the filter. there is another option of course, and that is to go active with a Behringer / DBx and a couple of amps.

Steve

It just means you need to move the PLLXO in front of the Zen. You are already looking at a couple amps if you are considering a PLLXO.

http://www.t-linespeakers.org/tech/filters/passiveHLxo.html

dave

 

[aquapiranha]

Thanks again Dave. i have had a think and may want to use a plate / sub amp for the bass (which of course would have level /slope etc controls) and the Decware in front of the 206's. I will read the link you sent, it is about time I learnt!

Many thanks Dave.

Steve