26 replies to this topic

[RS25WA]

Hey all,
just wanted opinions/recommendations/advice/comments on my present system:
Alpine CDA 7998R
Alpine MRV-F540 80rms x 4 amp running
MBQ PCE216 splits up front and
MBQ RKC213 coaxials rears
Alpine MRD-M500 500rms x 1 running
Alpine type R 12" Dual 4 ohm voice coils.
Rockford 1 farad cap
Dynamat extreme all round and Dynaxorb pads behind front splits.
i really like lotsa midbass.
and i was just wondering how i could improve the system.
happy with the subbass stuff for now, wanna focus on the SQ of the splits...ideas that occured to me would be to:

1) Bridge amp into 200rms x 2 into splits and get a smaller amp for rears (not that important anyway right)

2)Bi-amp into splits with the present 4 channel and get a smaller amp for the rears.

problem is with option 1, my THD on the amp goes frm .08 running off 4 channels to .3 bridged. does THD matter much?

any other suggestions? just wanna get as much out of my splits as possible. Believe that these splits are rated ar 130 rms? How low can these splits go? what should i HP them at?

thx.

[NTY1]

I have a similar setup as to u.

MB Quarts PSD216 at front.
MB Quarts RCK 216 at rear..

Front Amp: Ausdion VRX206 Rated 65WRMS x2
Rear AMP: Rockford Power 400.4. 50RMS x4 (2 channel used for the rear speakers.

they sound unreal.

preivously i used a PSD 200 KENWOOD amp (2 x 100WRMS) to power the front. they have higher rated power than the Ausdion but they sounded only half as clean as the Ausdion. the Ausdion gives out so much more details in the music.

so my advise is THD is importan and power rating isnt all that importan.
daily use around 70WRMS of clean power is plenty.
if i was you i would sell the apline and buy a high end 2 channel amp to run the fronts if u want the best out of the MB's, instead of bridging the apline.
than again it;s your money.

[HISPL]

Hi pass at about 80hz-100hz with a nice steep slope,
I would recomend getting some serious power for your front end, something like two Crossfire VR602 amps Bi Amped into your splits and use your 4ch to run the rears bridged then fade them almost all the way out.

Them get some more power 4 the subs to balance it all out.
Headroom is one thing you can never have too much of.

Having a heap of power means that you don't have to crankl the sh#t out of it to be able to get some output and when you don't have to crank it the deck is putting out less distortion, the amps are puting out less distortion and then the speakers are reproducing less distortion.

It is all one big chain and the weakest link will obviously b your downfall.
Remember if you high pass your full range speakers at a higher freq they will handle more power if you don't mind the sound of the system when the speakers are high passed at 100hz that would be OK.

This is why I would recomend most people spend more on amplification, most people skimp and wonder why their $800 splits sound cr*p when they turn it up coz they bought a $400 4ch amp to run them and the rears. that puts out 50wrms per channel..

In my opinion I think 100wrms is barely enough to run a front end with nice speakers like th Quarts,
look at the Monaro that Incar Phil is building, the power goiing into the front end is pretty insane, you can do the same thing on a smaller lever and get good results.

A bloke I know had some MB Quart Qs in his car with about 200wrms running them sounded good.

The Crossfire amps I recomended would give your splits 300wrms. and you would then have plenty of headroom.

With "full range" speakers distortion is easier to hear than say subwoofers as they play in the most sensitive part of our hearing range, any chance to minimise distortion and maximise headroom should b taken.

Obviously you have spent some decent money on nice gear for your car, remember not to skimp on the power to go with it, you wont b taking the gear you have to its full potential.

Anyway this is my opinion on the matter.
I hope this helps

[RS25WA]

Their only premiums, rated at 130wrms....so wouldnt running 300wrms be abit overkill? i know its good to have more power than ure speakers can handle, but surely just running my 80wrms x 4 (total of 160 wrms to each side) will be good enough? then i can just get one of the smaller alpine V12s to run my rears off, maybe a T320 which is rated at 80wrms x 2. it is after all only rear fill and my impression is that its not very important?

[HISPL]

Remember that the 80w x4 RMS figure Alpine quote is @ 14.4v and in reality at 12v is closer to 60wrms x4.
If you high pass the speakers they will handle much more than the rated power the manufacturer recommends.
I had 250wrms per side running my Focal splits and they sounded great!
The splits were rated @ 75wrms.
They had a high pass of 80hz at 12db.
I would reccomend using the steepest slope that you can to improve power handline for eveday listening.

[ultim8DTM5]

Headroom is a wonderful thing

[RS25WA]

hmm highpass @ 80hz? using the deck crossover or the amp one?
might hp them at 60hz instead.......then lp my sub at ard 50-55...
really want more emphasis on the midbass.

[HISPL]

If you have the Fantom Face XL deck
(I'm not much of an Alpine person I can't remember all the model no.s)

I would suggest using the crossover on the deck at the highest slope (18db) from memory and then set the crossover on the amp as well.

This will result in what is called the cascade effect and you will have a steeper slope on it. If you choose to run the front end that low you will find it will distort at lower volumes.

Also remember that you will have two six inch drivers playing these lower frequencies rather than a 12 inch woofer.
The 12 inch woofer has much more cone area and will produce greater output than those six inch mids ever will at those frequencies.

I assume you mean that you want more midbass upfront.

The bad news is I would suggest that you get some eight inch mids in there!
The good news is that you can cross over the splits you have to run from 400hz and up and run the eights between 60 and 400hz.

Hope this helps you on your quest for audio nirvana!

[RS25WA]

thx for that HISPL.
will worry bout tuning later...
just thinking bout biamping the splits...should work well though....even if u get 60wrms x 4 @ 12v, u still have a total of 120wrms going towards each side...that's pretty close to what the PCE216s are rated...
plus according to my digital cap, my voltage remains constant at ard 13.8-14, so i think ill get more than that.
sadly, 8 inch drivers are out cos they'll require custom pods etc and i wanna keep the stock look....
btw yeah its the fantom face deck.
so what should i set the crossovers in the amp at? cos i think that the amp settings arent as flexible, think the nearest would be 75hz...

[BlackRain]

I know 12V is a more conservative measure, but that's assuming ur listening to ur car without the engine running.

With the engine running, my car runs at 13.8 when it's stationary for a long time, and 14.0+ when on the move, so I think u'd get pretty close to Alpine's rated power, especially since most of their amps come with extra power from the factory anyway.

Inflexible amp, I assume ur talking about the MRD-M500 right?
I actually have my sub lp'd pretty high, 100Hz and it still handles it beautifully.

[HISPL]

Well I reckon it is not that flexable coz it is not starpable for future upgrades and it is not full range either.

At least with other mono amps you can strap them for more power into one coil or one sub.
even if they are not full range.

Or with say a US Amps 2000x it is full range and can be used for other applications if you upgrade later on.

That is just my opinion on that one.

Nothing wrong with the Alpine MRD500 but why buy all the w@nk factor of the digital display when you could buy close to double the power for the same money???

[Xristo]

correct me if im wrong but the MRP amps from alpine are the non v12 amps right?

anways bridge the channels together to run your fronts and run the rears off the deck. HP the splits as low as you can, in this case would 75 as u state you cant go lower. dont worry about the thd figures...it will be inaudible.

if all else fails, the conclusion must be made that some speakers create more midbass than others. its just the characteristsics of the speaker.

[LexARSE]

why dont you just bridge the amp to the front and see if it sounds better. If it does then leave it and run the rears of the HU. (If it has an amp)

[RS25WA]

yeah well the mrdm500 is here to stay cos i already have it....like i said..want to focus more on frontstage now than the bass...thats secondary....
my deck has no internal amp xristo, and thd doesnt matter? are u dead certain bout that? and obviously different speakers have diff midbass characteristics...heard the MBs can go real low but i go them cos i liked the tonal quality....

[BlackRain]

HISPL said:

Well I reckon it is not that flexable coz it is not starpable for future upgrades and it is not full range either.

At least with other mono amps you can strap them for more power into one coil or one sub.
even if they are not full range.

Or with say a US Amps 2000x it is full range and can be used for other applications if you upgrade later on.

That is just my opinion on that one.

Nothing wrong with the Alpine MRD500 but why buy all the w@nk factor of the digital display when you could buy close to double the power for the same money???

Don't assume people buy it just for w@nk factor. On a certain budget, picking the amp with the most power isn't always what you're gonna do.

The choice of amp depends on what suits your system in terms of sound quality, tuneability, power matching (not EVERYBODY needs the 2000WRMS on tap that the US amp can give. I'd feel sorry for my alternator.) and perhaps even some brand matching, which I don't think there's anything wrong with as long as ur sticking to reliable and proven brands. Another big thing is the size of the amp, well for me anyway, cos I have sh!tall bootspace to play around with.

I think headroom is good..but there is such thing as overkill.