Hey guys-

I like the Blaupunkt speakers, but the crossovers are just not hacking it. The speakers tend to distort around 60-70HTZ, and the x-over allows anything higher than 40HTZ through. I was wondering if anyone could recommend a decent set of crossovers, or even a decent EQ (must have 4ch output and a sub control) that will allow me to taylor the frequencies that the drivers will see.

I am going to be getting a Boston GT-22 (Or I might just upgrade whole system to MRV-F345 with the rear channels bridged for the sub). I think these amps have a decent built-in x-over, but I am looking for tunability.

Thanks

John

 

John, busy day at work, so i was taking a glance at lunch... i don't have time to really crank on this now, so i'll hit some quick questions first:

you'll have to remind me a bit more about your system... did you amp your fronts? i simply don't recall.

what are your bass and treble settings at?

MX on? off?

crossover for the fronts is set at?

i don't know that the BP crossovers have a highpass for the mid drivers. they are probably full range.

at what volume is it distorting?


how much do you want to spend on an EQ. regretfully they can be pricey for the nice ones, or ridiculously cheap for the junk. not a whole lot inbetween.

 

Hey Phil-

I am not amping the fronts now. Like I stated in my original post, I will be getting either a Boston GT-22 and keep my Infinity for the sub, or get the Alpine MRV-F345, and bridge the rear channels for the sub. I am leaving the S-pods un-amped, because of their proximity to the ears.....they shouldnt need it.

I have x-overs for all sets (OCDa660 in the doors and TsC540 ( I think....they are the 5.25" TsC series). They provide decent sound, when the bass doesnt rape them. The x-overs basically have only 1 adjustment, and that is for a -3db to the tweeters. Nothing special. I think the drivers are pretty much seeing all ranges, up to the tweeters (including bass and sub-bass). I think they are pretty much glorified bass-blockers.

Bass is set at +4 or +5 out of 10. Not too high. The treble is set at +7 out of 7. The tweeters are kind of buried under the A-pillars, so I want those all the way up.

MX on/off?

It starts distorting around 20 on the Alpine 9851 HU.

Looking for the EQ as a possible x-mas gift....sooo up to around $200.

I may not need an EQ when I amp the fronts, due to the HPF on the amps, but would still need one for the rears. I am a stickler for tuning, though, and am always tweaking the system to match the kind of music I am listening to (picky ears). An EQ would make this process a lot faster and easier.

John

 

to apply an EQ, you'll have to amp. my money would be on the fact that once you amp, you won't need the EQ.

MX = Alpine's loudness technology. perhaps your model doesn't have it.

i doubt the crossovers are blocking any bass to the mid/bass drivers. so, they are seeing full bass signal, and you're 'bumping' up the bass signal w/ the +4 or +5. this is actually sending more power to the speakers, specifically around those frequencies.

now, considering the power supplied by the HU is probably not enough to mechanically distort the speakers, chances are you're hearing amp clipping distortion. and turning up the bass actually demands more from the amp.

in an attempt to explain this with an analogy (it will be flawed, but let's pretend it doesn't have Mac truck sized holes in it. ) ... imagine your amp as a room with a trampoline in it, and your speakers are the guy jumping on the trampoline.
now, the height of the jump is the power being put out... the more power, the higher the guy flies. if the room had an infinitely tall ceiling, your only concern would be flying so high, that your speaker dies due to impact when he lands on the trampoline. (overpower damage). but, amps aren't generally infinitely powerful... they have a limit. so, now, our room has a ceiling. the less power your amp makes, the lower the ceiling. so... as you turn up your volume, our guy bounces closer and closer to the ceiling, and eventually he starts hitting it. as you turn it up even more, he hits it harder, and harder. our speaker doesn't sound right anymore since he's being prevented from flying freely, and eventually, you can cause damage with clipping distortion.
the room he has before he starts hitting his head is called dynamic head room.
... now, the analogy breaks down in a ton of ways, but the basics are still true.

on this page: http://www.bcae1.com/installationprimer.htm
skim down to the Misinformation and Ignorance section, and read parts 1, 2, 4, and 10.
on this page: http://www.bcae1.com/amplfier.htm
skim parts, but read the sections after Amplifier Output

some of this is already things you know or have read, but hopefully, the package will help you understand what you are hearing and why...

 

Phil-

The distortion is coming from speakers that are not currently amped. When the volume get to level 20 at the current settings, the drivers go NUTS. Sounds like they are farting all over the place. I think its because they are seeing frequencies that require a higher x-max to really produce with any effectiveness (less than 60 HTZ). Not too sure what is causing the crappy sound, so I figured it was the frequency range, as the speakers are fine at lower volumes, but surrender at around 20 on the colume scale. These speakers are not amped, unless you are talking about the internal amp in the HU.

I guess I will put it off, as the problem will probably be solved by the amping of the speakers.

Any takes on the Alpine MRV-F345 or the Boston GT-22? Not sure if I want to have 2 amps....but I think the Boston will fit under the driver's seat.

Thanks

John

 

i was talking about the amp in the HU.


but farting noises? hrm, that's usually not the way clipping distortion is described.

you don't happen to have a test tone cd do you?


if nothing else, amping the speakers will give you a set of crossovers in the amp that you can use to filter out deep frequencies.
regarding a choice between the Alpine and the Boston? i do own a Boston amp ya know...

still, i think both are quite capable amps.

 

Nope....no test CD, but I can make one. It just sounds like the speakers go crazy at that volume level. It is sort of a clipping noise, but much more extreme. I will just wait til I get the amp.

Thanks

John

 

I think Phil hit it right on the nail by saying, get the amp first then see what happens.

When you amp the speakers they will sound totally differently.

If I am reading this correctly, you stated the speakers are distorting at around 60 to 70 hz, most mid bass drivers cant play that low, I know my Utopias would start to distort at 60 hz, so I had them crossed over at 80 hz with a 12 db slope. (or was it 6 db?).

Anyways, sound like your sending too low of a freq to them, that and the low power you are sending them is just making the distort. As for the fart noise, check your pants? =), j/k, i never heard clipping like that, but it does sound like your describing just some furious distortion.

I just ordered a ALpine MRV F545 myself, and cant wait to get it. I will let you know how it is. I have seen others throw the boston amp under the seat.

 

what kind of speakers do you have and how is the installation? did you check your speakers?

what radio do you have?

 

As for the speakers....check in my original reply to PJK3. It tells exactly that. I am running an Alpine 9851 HU.

Pikkashoe- Let me know if you like that amp. I am considering that one as well, and just upgrading speakers. I got these speakers for cheap ($50), but they retail for $200 and produce good sound. They are limited to 80WRMS, though, which is why I might just swap them out.

Looking at the Alpine SPX line. I think I might swap everything out for Alpine (or maybe a combination of Boston and Alpine).

Thanks

John