# Alpine Type X Components SPX-177R



## ZStyle (Oct 17, 2006)

This is my first post to the forum! Although I have been reading for some time i've come accross a questions that cannot be solved simply by reading the threads. Or at least that is what it would appear....

I have an Alpine 4 Channel amp MRV-F345 connected to Type X Components SPX-177R

The amp is rated for 75Wx4 and i'm going to bi-amp the components. 
Channels 1/2 are going to drive the tweeters and 3/4 will drive the midbase.
The Midbase are rated at 35W and the tweeters are rated at 25W.

Will I blow the tweeters by bi-amping them on a channel that has 75W? There should be a protection circuit in the crossover that will prevent this right? Can I just turn the gain all the way down on channels 1/2 to ensure they don't blow?

I was told that these speakers are really underated so I think I should be fine i just wanted to check.


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## ///MJay (Aug 22, 2006)

Welcome to the forum. You should be fine. The key is not your power, but your crossover settings. Make sure that you are using your speakers with in the range that they were designed to play and they will sound 10x better with out the passive. Bi amping will actually give your tweeter more protection. When you use the passive and the bass signal clips it is also fed to the tweeter. If you bi amp correctly you prevent this from getting to the tweeter. Correct me if I am wrong but that is how I understand the basic advantage of biamping.


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## ZStyle (Oct 17, 2006)

Ok so you don't think they will blow. Good.
Now to figure out these settings. Perhaps I'll post my thoughts after I review this a bit.


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## solacedagony (May 18, 2006)

The power is fine, just make sure you set your gains either by ear or DMM/Oscilloscope.
The advantage to bi-amping is that you can apply processing to any of those channels individually (T/A, EQ, level controls, etc.)


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## ZStyle (Oct 17, 2006)

Solacedagony: So even though my tweeters are rated at 25W and they are connected to a 75W channel I should still set my gain the exact same as how i do with my subs? I was thinking that because they are only 25W i would just put my gain to the lowest.

Ie: - Bring HU 3/4 volume - put all eq extra on HU to flat - Put all amp 'boosts' and gain to zero or flat - put oscilloscope on output of amp and turn up gain untill clipping is noted and then back it down until a clean single is being generated.


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## solacedagony (May 18, 2006)

Gain is for matching the preamp voltage to the input stage of the amp.
I would think that the pass crossover would still include resistors and things to match the drivers' volumes somewhat, so you would want to keep each amp putting out the same amount of power still (As I understand it.)
If anyone has anymore to add to this for clarification, please don't hestitate to post.


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## ZStyle (Oct 17, 2006)

Is there a rule of thumb or mathmatical way of determining exactly what Hz your filters should be set for. I mean you want some overlap from each speaker but how much? Is it all done by ear? 
Mids: 25-8Khz 6.5"
Tweet: 600-60kHz 1"
Sub: 24-200Hz 10"

I'm thinking to put my HP filter (tweeters) around 1khz. LP Filter (Mids) around 3-4kHz
and my sub (different amp) around 100Hz


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## mvw2 (Oct 2, 2005)

You're not overlapping in that way.

What are you going to use to control the crossovers? Let's assume you have a HU that's capable of x-over control. Many higher end models from most companies have 2-way + sub x-over control built in. This makes turning a standard set of 2-way components into an active setup a breeze. Generally the front RCA outs are your highs and the rear RCA outs or mids. Then there will be seperate sub RCA outs for subwoofer control. There will be 5 or 6 RCAs in all(depending if your subwoofer is output in stereo or not).

A good starting point is around 3kHz. Generally, most tweeters can play well down to 3kHz and most midrange woofers can play up to about 3kHz without a lot of issue. You'll probably find yourself somewhere around 2kHz to 3kHz.

Where you cross depends on the drivers. For your woofer, at some point as you tell it to play higher and higher, it will become less capable of moving fast enough to accurately play that frequency. Or, the material used in the cone may start to have its own vibrations. Reguardless, at some point, distortion sets in. It could be a loss of clarity. You may drop in output(quieter), it may beam(get loud/noisy). At some point, you move outside of its optimum range. This is what you don't want to do.

The same applies for the lower end. Low frequency requires a large amount of air movement. This mean the cone area has to either be large or the driver must have a lot of excursion. This is why subwoofers are so big and have crap loads of excrusion. When you move down to a 6.5" woofer or worse yet, a 1" tweeter, both cone area and excursion are limited. You will be physically bound to a lower limit. For a tweeter, this may be 3kHz, 2.5kHz, or 2kHz. Not many tweeters can play strong under 2kHz, and if they do, they're probably expensive. You just run out of excursion and clean, linear cone movement. Now since excursion is volume dependent, how low you can go depends on how loud you play. To some extent, you can force a driver to play lower, but you're sacrificing how loud you can play. As well, if you move out of its sensitivity range, you may have to add a bit of EQing to get low end extention out of the driver. You may have to boost your 6.5" woofer quite a bit just to get it to play flat down to 100Hz or 80Hz.

This optimum or "natural" range that the drivers have kind of creates appropriate x-over points. You have some fiddle room, but it requires a little massaging to get the drivers to play outside of their optimum range.

As a side note, your Type-X drivers are Vifa's XT series. Feel free to look up info on Vifa's XT line and get info on your drivers. The Type-X set apparently uses the XT19 tweeter.


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## GRexer (Jul 18, 2005)

Well... pardon me, but i've fiddled with the MRV-F345 before, but somehow, it's gain is not like our regular amps based on a vario-resistor knob, it's actually done digitally with a couple of "setting options", basically if you are a newbie, it's good, considering you just choose the gain levels based on your HU's output(it's listed like 4v, 3.5v 2v and the kind)

What i would say is set the gains based on your HU's output first and see how you like them, then only u start adding or reducing the gains.

But just curious though, are you bi-amping them thru the passives? Or going to go active?


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## ZStyle (Oct 17, 2006)

I don't actually know what you mean by bi-amping them thru the passive or active. So let me describe my setup.

Alpine CDA-9857
1 RCA going to MRV-F345 -> SPX-177R Alpine Type X 6.5" components
1 RCA going to MRD-M1005 -> SWX-1042D Alpine Type X 10" 

From the MRV-F345 I will go channel 1/2 into each crossover to the tweeters. Channel 3/4 into each crossover to the mids.


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## ZStyle (Oct 17, 2006)

MVW2: I'm thinking I will control the crossovers with the MRV-F345 amps filters LP and HP filters for each channel


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## GRexer (Jul 18, 2005)

The way you are doing it, you are bi-amp-ing your components thru the passives, you *should* set the amp filters to FR(Full Range) instead.


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## mvw2 (Oct 2, 2005)

You might be able to, but looking at a couple sites, it's one or the other, 30-400Hz OR 600-8000Hz. I'm not sure. If you can control both simultaneously, good. If not, you simply pick the higher range, cross somewhere in the range of 2kHz to 3kHz, and you feed the woofers everything below(no high pass between the woofers and sub) which means the woofers are playing 50Hz, 20Hz tones although they shouldn't.


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## Jroo (May 24, 2006)

You should be fine as long as you really watch crossover points. I have the type x 5 1/4 set and have mine biamped. I run the tweeters with the front channels of my jl 300/4 (75 watts) and the mids get my jl 300/2(150 watts). I dont have any problem other than adjusting gains and having to xover higher than I wanted. My midbass broke up pretty badly until I raised the xover points.


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## ZStyle (Oct 17, 2006)

GRexer: Why would you suggest setting each channel to full range instead of using the HP or LP Filters? 

mvw2: It looks like the F345 you can select each channel to use LP or HP or full and then set the frequency you wish to use. So it appears I can set a LP and HP filter for different channels and just set my frequency I wish it to play in.

Jroo: Nice a fellow X users  Do you have any suggestions for midbass frequency range and tweeter frequency range based on your knowledge?


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## dawgdan (Aug 10, 2006)

FWIW, the Alpine Type-X passive X-overs are pretty much the finest, most adjustable passives on the market right now. I am picking up a set shortly for a very small sum. I really like the ability to adjust the crossover point and make sure everything is phase-corrected. Can't wait to get my hands on them.


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## Jroo (May 24, 2006)

I will go back to my amps and crossovers to see what the settings were left at. I just did the set it and forget it and havent messed with them since. From memory the high pass started and 100hz but I had pretty bad break up. I believe we ended up taking the midbass up to 125hz and left it there. I am going to go three way and put my old Infinty beta 6's back. Again, I will go back and check. The xover on this set in truly incredible, probably the best I have seen. I have the big blue Infinity beta xover and a set of MB quart Q series and these offer way more flexibility. I do have to say I have heard some better speakers than the alpines. My old JBL 504 gti's blow my alpines away when the work correctly.


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## ZStyle (Oct 17, 2006)

Well I think I'm in over my head. (such a noob)

Hooked up my audio and tried to setup gain and cutoffs and everything sounds like poo.

From my MRV-F345 I have channel 1/2 connected to the Type X crossover input for my tweeters, and on channel 3/4 connected to the crossover's mid input.

If the crossover's on those Type X are soo good is that where I should set the frequency at? I mean my HU and my amp and now my crossovers are all able to do the cutoffs and such for frequency, so should I leave my amp at full range and my deck at full range and only set the crossover points in the type x crossover?

Those type X tweeters (Vifa's XT19): Should they be crossed over at 3kHz exactly? Is there an exact number that these should be set at? The manual for the crossovers in way over my head. It looks like in the crossover you can only simply pick a value at which the crossover will happen? Shouldn't I use the LP and HP filters on my amp to set the output of the amp to each channel? Wow I took on such a huge project I think....
http://www.alpine-usa.com/images/products/documents/SPX-177R_om.pdf


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## ZStyle (Oct 17, 2006)

Also on the crossover there is a jumper to set for the tweeter and what I can make out is that you put a jumper in for one of the followings
+3db
+1.5db
0db
-1.5db
-3db

....what the heck do i set that for....


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## ZStyle (Oct 17, 2006)

http://sound.westhost.com/bi-amp.htm

Well what does everyone think he says to not use my passive crossover.....

The most common question I get is ...

"Do I need to disconnect the passive crossover in my speakers?"
The answer is ... Yes, otherwise you are not really biamping at all.


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## CBRworm (Sep 1, 2006)

make sure you remove the two jumpers between the inputs

the way you are hooking it up you are using the passive x-over to set the slopes and freq's. you can run full range into both inputs but control the volume seperately. that's different than active.


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## ZStyle (Oct 17, 2006)

Yes the two jumpers are removed. So is that the best setup then to run full range into the crossovers and then control the slopes with the crossover itself?


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## CBRworm (Sep 1, 2006)

Yes, if you are using the alpine passive crossovers either send them full range or set the xo points on the amp well outside the range of the passive xo's.


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## radioflyer07 (Nov 9, 2006)

i'm considering this same setup for my 97 vette. But i'm going the route of 2 MRV F345 amps and SPX 177a in the front and rear. I'm going to bridge the amps into 2 channel for 175W per channel. Let me know how your's sounds.


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## solacedagony (May 18, 2006)

ZStyle said:


> http://sound.westhost.com/bi-amp.htm
> 
> Well what does everyone think he says to not use my passive crossover.....
> 
> ...


You are still bi-amping, you're just still using your passive crossover to distribute the signal as opposed to an electronic (active) crossover. That passive crossover has the bi-amping option, where many do not.
You don't need to use any crossovers on your amps unless you need to high pass your woofers (not sure if that crossover high passes them or not).

Edit: If you look at bottom of that webpage's "Common Question" section, he comments on "passive bi-amping".


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