Understanding the stereo ratings ???

[steptoe]

OK, done a search here where people speak plainly and found nothing to answer my query on speaker matching.

Like ian059, I also bought an ALDI special in 2008 or 2009.

Only just installed it the last few weeks

The thing is described on its booklet as 4x 50W ppo (peak power output)

They were sold as a unit without speakers or any recommendation.

I replaced the original 4" Clarion fuzzkers with 4" Fusion CP-FR4020
@ $38 pair, just got the rears installed in the doors of the Brumby at the moment, considering fronts in side of console

These are rated at:
peak power 180 Watts,
rated power 35Watts
42Hz to 25kHz
4 ohm
86dB

max number on the volume knob is 45, anything near above thirty two sounds a bit zzzzzzty

4 x 50 W ppo pushing just two of the speakers above - is this my problem and should I hook up the other two to absorb some fuzz, or do I need to get some speakers with at least a 50Watts rated power to match the 4 x 50 W rating of the budget head unit?

It is better than the old Clarion tape radio by a long shot, I did not expect distortion at such low volume. I did tell sales fella what rating my unit had. I opted to buy the second cheapest speakers in 4" he had, then he upgraded as they were his demos, next up was $58 sold for $38

[Brumby Kid]

You have a 200W headunit, or 50W for each of the 4 speakers.(thats what the 50 x 4 means) Just make sure your speaker is rated higher than this or you will blow it up!
I think, just make sure your speakers are of a greater Wattage than the final wattage coming out of the headunit.

[Smokey]

I'm sure some of the stereo gurus will set us all straight. But, I thought it was better to match speaker to head unit rather than over power speakers, under power HU (head unit).

4x50wppo is more like 15w RMS no? So a speaker just higher is optimal.

However if your carefully not to push the speakers hard, ie distorting for x period. Then you can probably spend the money on speakers once and upgrade the HU down the line.

Prob all wrong, let's see what others add...

[steptoe]

shees, it is worse than trying to convert metric to imperial isn't it! Not just a straight conversion, worse if there is three ratings . Tone Loc's Funky Cold medina at 32/45 volume is sqeaking now at the speakers.

I advised the dude of what my cheapo unit was rated at and asked for speakers to suit, thinking he may have erred

Noting most head units in catalogues are rated at same 50 or 52 x 4 , so mine is nothing out of the ordinary

[Davidov]

50x4 means that at any time no more than 50W will be put to your speakers. Its actual RMS is roughly 12Wx4.

This means you only need speakers with a rated power greater than 12. It is always better to get speakers that handle more than they are fed.

Speakers will never stay clear to the max volume on a head deck, you just need to find the right volume setting that the speakers can handle.

Those speakers you have handle far more than your head deck can ever dream of putting out, if you want more volume and sound quality then you will have to install an amp and put in some better speakers, otherwise what you have is the best you can do.

There is no head decks out in the normal price bracket that do more than 52x4 peak. To get more requires an amp.

[pitrack_1]

Steptoe,

Like ian059, I also bought an ALDI special in 2008 or 2009.

1) An Aldi special is an Aldi special...

Only just installed it the last few weeks

2) Cripes, someone as slow as me

The thing is described on its booklet as 4x 50W ppo (peak power output)

I just posted about something similar yesterday for Scubyroo, see http://ausubaru.com/forum/showthread.ph ... post185092

I replaced the original 4" Clarion fuzzkers with 4" Fusion CP-FR4020
@ $38 pair, just got the rears installed in the doors of the Brumby at the moment, considering fronts in side of console

These are rated at:
peak power 180 Watts,
rated power 35Watts
42Hz to 25kHz
4 ohm
86dB

max number on the volume knob is 45, anything near above thirty two sounds a bit zzzzzzty

and

shees, it is worse than trying to convert metric to imperial isn't it! Not just a straight conversion, worse if there is three ratings . Tone Loc's Funky Cold medina at 32/45 volume is sqeaking now at the speakers.

The Peak Power/Peak Music Output rating is simply to quote a higher number. See http://en.wikipedia.org/wiki/Audio_power for an explanation. You're probably looking at ~8W RMS for the Amplifier in the head unit.

So you've got speakers rated at 35W RMS driven by an amp at ~8W RMS. This is underdriving, particularly bad for speakers. What happens is the amp runs out of puff (hits its limits) before the speakers do, and basically the driving current flatlines at its max. This is called 'clipping' and is both distortion and bad for speakers, possibly the amp too. Hence your zzzzzzty.

You're actually better off overdriving somewhat (higher amp power than speaker power) and just not turning up the vol to the max. You minimise the distortion and don't hit amp limits. The speakers will probably handle the extra power as long as its not constant or excessive.

Noting most head units in catalogues are rated at same 50 or 52 x 4 , so mine is nothing out of the ordinary

Those, 4x50W e.g. the JVC, Sony, Pioneer, etc. will be RMS power, so perhaps 4x300W peak power output. If you don't want ipod control and MP3 etc input you should be able to pick one up for <$100 now.

I replaced the original 4" Clarion fuzzkers with 4" Fusion CP-FR4020
@ $38 pair, just got the rears installed in the doors of the Brumby at the moment, considering fronts in side of console

It is better than the old Clarion tape radio by a long shot, I did not expect distortion at such low volume. I did tell sales fella what rating my unit had. I opted to buy the second cheapest speakers in 4" he had, then he upgraded as they were his demos, next up was $58 sold for $38

The amp MAY be expecting all the speaker channels hooked up, less may make a difference to how it behaves. You could bridge the left front and rear outputs into a single left speaker, ditto for the right. This will allow you to drive the speakers from two channels power each.

My old Pulsar had a matched low powered system which sounded quite reasonable until I had to replace the sun-damaged rear parcel shelf speakers with newer, higher power rated ones. It only had 4x8W from the tape/tuner head unit driving 4x8W 4" dual cone speakers...

Hang on a moment...The speaker and head unit were Clarions..! Aaaark!

[Alex]

when you hook up cheap speakers to a cheap deck youll experience distortion at a relatively low volume (but still probably good enough in a smallish cabin of a brumby)

the speakers you have arent worth amplifying and youre probably getting the best you possibly can out of them at the moment. Maybe just a play around with the equaliser settings is all you need.

In higher end equipment its better to overpower a speaker than underpower it. The amps tend to clip and distort before the speaker hits its limit when its underpowered, its pretty bad for the voice coil. For example im running 150WRMS into two sets of splits in my liberty, the speakers are rated at 125WRMS, my subwoofer is getting 500WRMS per voice coil (a true 1000WRMS over both voice coils) but the speaker is rated to 600WRMS. It makes the sound super responsive and punchy.

When looking at stereo power ratings basically scrub out the max power output. I laugh when i see pioneer 1000watt max subwoofers but are actually 100WRMS (or nominal). If i were to use this way to calculate my subwoofers output i could say its 5000watts yo!

theres heaps of other more technical things to look at but only really make a difference in serious systems, like speaker efficiency etc. For instance your 4inch fusions are 86db which is pretty terrible for a 4inch meaning theyre pretty inefficient. My fairly high end focal speakers are 125WRMS but they also are extremely efficient at 110db, meaning you could get away with running a smaller amp.

hope this makes it abit more clear (or maybe even worse)

then theres the different ohm ratings on speakers too

[steptoe]

mmmm, thanks, trying to absorb things

[pitrack_1]

For knowing what you're talking about.

Or should that be 'sounds like he knows' -sorry, couldn't resist, bad puns a speciality!

[steptoe]

I found this to help understand the acronym for starters,

Root Mean Square. So, it does not stand for Real Music Sound

one rumour gone !

"RMS is the process used to determine the average power output of the speakers over a long period of time. RMS is derived from an equation which produces the most mathematically accurate measure of a speaker's power output. The RMS value is often seen listed as "Watts RMS" on product packaging.

The alternative to RMS is PMPO (peak momentary power output) which represents peak output measured in microseconds rather than over a long period of time. "

Also emailed fusion to ask if I have been sold a suitable speaker to suit the rating of my head unit. Might have to go back to speaker seller with Tone and see what he has to offer.

The end result of this stereo is nothin like another cheapo stereo I have had in the past - BOSS , took many years before a speaker shat itself