Axiom Home Page Forums General Discussion Stereo Stereo amp recommendation?

For music, I would still run the M22s at full range... M2s need a bit more help from the sub than the M22s do...

I find things still sound a bit better in "large" even with the HK bass management; just that the difference used to be significant and now the difference is quite small.

Again, I don't really know why the x-over at 80-100 hz makes any difference in the first place... I need some better A/B switching gizmos to be 100% sure of what I hear.

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ok...as for the crossover, I really hope the highpass filter from SVS sub wouldn't mess with the sound quality, if the imaging is going to suffer then I'll either bite the bullet and build one myself, or forget about the highpass and run the M22ti at full range.

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Demasoni:

Well based on my findings I found that external crossovers work the best if one does not have a Surround Receiver with a sub out or if someone wants a full range stereo listening with mains and a sub. I use a Mirage LFX-1 active crossover which is hard to find but there are places that have em and they work amazingly. You can use low pass or high pass type connections. Low pass is okey but at low pass you can not really control the sound level. It is fixed. Using high pass is good because as you raise the volume level on the poweramp the sub volume level will also increase.

My setup is weird but works well. I wanted the full signal sound going to my speakers without any interferance. So I have the output of my mains going to my main speakers (like everyone else). But the bananas I have coming out of my poweramp are "stackable". So you can attach another set of speaker wires to the end of the stackable bananas and send the same signal to the active crossover high pass input. So also the crossover receives the full signal. From the active crossover I set it to where my speakers rolls off I'd say around 50hz and the signal coming out of the active crossover in both the high pass or low pass output is from 50hz and lower to fill in the low end. So the full signal gets passed to my speakers without any interferance. And the same signal get sent to the active crossover which only passes 50hz and lower to the sub...A nice full range of sound I get with this setup. The LFX-1 is used around $150-$250



See the out connectors of my power amp has WBT locking stackable banana connectors..RED+ & WHITE-. Connected to the end of the WBT are Ultralink locking bananas RED+&BLUE-.
The wires from the pair of WBT speaker wires(CAT5 network cables) go to the speakers. The pair of Ultralink speaker wires go the LFX-1 high pass input which is above my power amp. From my active crossover I have a RCA sub connector out to my sub.

Mirage LFX-1
http://spacelofts.com/h30/mini-IMG_2397.htm

Couldn't the Outlaw Icbm do the same thing as the Mirage,It's only $249 new and $199 from B-stock.

Outlaw works very nicely. BTW Saturn, neat cable arrangement. Not the rat's nest so many backsides look like.

Bridgman, what are those speakers? They look like M22s except for the MTM arrangement.

They are VP100s. Don't ask

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Couldn't the Outlaw Icbm do the same thing as the Mirage,It's only $249 new and $199 from B-stock.

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Yes thats an external crossover.

Hello Bridgman

Funny, but I considered using a pair of modified Meraks in the same way - Meraks were built by Axiom, have the same shape as your VP100s but use a pair of 6.5" drivers which I replaced with a pair of Axiom aluminum drivers. I like the Meraks for their horn tweeter. With upgraded caps and Axiom driver upgrade these Meraks sound terrific.

Saturn,

thanks for the great advice :-)

I was looking at some diffferent crossover circuit diagram and also checked out some external crossover and eq last night as well. My first concern is, active crossover tend to robbed power and they will color the sound to a certain degree depends on the type and brand of components I'm going to use. I do not know how the Axiom and SVS's drivers going to react toward different filter slope. If I'm going to buy one, I sure as heck going to need the complete list of components they used, If I build one from scratch, then it'll be extremely time consuming and going to cost $$$$$, a first order design(6dB/octave), it is affected less by impedance variations than higher orders, BUT...the drivers will be producing sound at frequencies that are very likely outside their upper or lower limits. At low powers (<10w) is probably not a major issue, but it becomes much more important when I'm pushing >50w. The HK3480 is 120wpc so it's going to be much worst, scratch that!! :-)

Ok, so I go 2nd order filters(12dB/octave), it's better at keeping unwanted frequencies out of the drivers, but it's more complex, and affected by impedance variations to a much greater degree, it's very tricky and not a good idea to simply use off the shelf caps and coils from...say partsexpress, the capacitance used must remain predictable and constant over time and power as well. The kicker is, the possible variations(especially those caused by voice coil temperature) can totally ruin the sound regardless of the quality of teh components or care in making this crossover network. The whole design task becomes even more complex and the tolerances more exacting as the order increased, so 3rd(18dB/octave) and 4th(24dB/octave) order filters are going to be a MAJOR pain in the arse!!

And I still haven't take phase shift and filter alignment into consideration, no wonder Axiom Engineers designed their drivers the way they are!!! After much consideration I think I'll stick with the KISS rule to be on the safe side.

That's why the M3Tis sound so good. The driver runs free, direcctly coupled to the amp, and the tweeter gets a really simple single capacitor and resistor.

Whatever the HK630 does in "small" mode is pretty good in terms of keeping the imaging, but I have no idea what that is other than knowing it uses the DSP, ie I don't know if the filter implementations are 6, 12, 24 dB/octave or whether any special type of filter was coded in the DSP.

My guess is that the HK uses 24db/octave because going through the HK crossover seems to raise the bar yet again in terms of how loudly the M2s can play "comfortably". With no high-pass they were not able to play as loud as I wanted without sounding strained -- with the PSB's 12 dB/8va they were able to play "just about as loud as I wanted" and with the HK's crossover I reach my limit before the M2s meet theirs. Crossover frequency was 80 hz in every case.

If you are OK with looking into an outboard crossover then I guess nothing needs to affect your sub purchase, ie you don't need to get any specific sub model in order to get the right high-pass filtering path built into the sub.

All I can say is that the best sound *seems* to be at the extremes... you get the best imaging (by a small margin) when the mains are getting an unfiltered signal, but you get the best SPL with a fairly sharp high-pass on the mains (matching the low-pass on the sub, of course).