Hi All,

Curious about the SQ from a PCX 4125 Precision Power amplifier?

I've done some reading... but nothing conclusive has come around.
Any people who own one care to comment.... what league would you put it in.
It will be used for subwoofer duties... but I'd still like to have high SQ. I've heard some reports that there is audible whine/hiss at somefreq. even with no input...:/

Thanks
_Ice

Some did, but it was a fault in the initial batch of amplifiers, which has been addressed and fixed.

SQ is not as good as the upper range amps. They are budget amps, after all.

Keep in mind that SQ differences between amps are usually quite subtle, especially with subwoofer duties. Your better off spending extra money on splits/subwoofer/install, and then look at more expensive amps.

People will be on here shortly to suggest lower powered, but better sounding, amps.

Liquidity - Do you know what the f*** you are talking about.

The PCX4125 came out with an RRP over $1200 from memory - hardly what I would call budget. Not the most expencive unit on the market but far from a budget or entry level type amplifier.

All of the PCX series were a little poorer on build quality compared to their predecessors and the newer series IMHO is well a little cheaper again.

They tend to get an audible hiss (or at least my PCX480 does) if the gains are high. But the only time ive ever had the gains on high was because i didnt read the owners manual and i accidentally hit the 20dB cut or what ever it is on the input for when you are running a hi level into the RCAs.

IMHO Awesome amps there was a PCX4125 on here a while ago forsale that I would love to get my hands on and a PCX2400 that id also love for sale ATM - I'd use them rather than my Audison VRx1.500 and VRx2.400 if thats a comment that means anything to you.

The PCX 480 and 4125 were known to be a little muddy on the upper midbass and some even say through out the entire mid-midbass range. I dont think I would use one to power a sub (a PCX2400 i would not one of the 4 channels though) as they arent the most efficient amps around and do get quiet warm.

I already have a 12" Ti Eclipse Sub. And thats all I have in my system atm. So I'm looking for an amp to match it. Its 4 (3.5) Ohm/coil DVC, 750WRMS. But apparently will go sweet up to about 1300WRMS.

The PCX would have been good 2ch's bridged/coil. But if thats not the case then maybe I wont go that route.

So I guess I want about 1 x 1000Wrms @ 2Ohm or 2 x 500Wrms @ 4Ohm.

Other options were:
Zapco 1100.1
AudioSystem F2-500
Rockford...?
Vibe M3
Vibe M4
MRD-M1005
E-Audio 3000D
EarthQuake D2
Phoenix Gold 1200.1

But they start getting near (or above) the $1000 mark, and I wanted to stay closer to $500-$700 if thats possible.

Cheers.

Might just have to wait till something else comes along in F/S.

there was a MRD-M1001 for sale a lttle while ago in the FS section and Androo had a good mono for sale not long ago too. keep browsin

The AudioSystem amp is $799 isnt it, I was planning on using one of these to run a IDMAX.

yep, around that price... can be had a bit cheaper.
But I think its the best value of them all...especially brand new. But probably not the best in SQ too.

I owned the exact same PCX powerclass series amplifier and let me tel you it is an awesome piece of equipment.

People that have never used Higher end equipment or who dont know anything about a brand shouldnt be saying anything regarding this thread especially when its the wrong information.

The Precision power powerclass series had a RRP of over $2000 from memory because when i bought mine it had a sticker of $2399 retail.

Expensive amplifiers and i definitely didnt notice any kind of hiss from it. Very clean and very powerful. Rated at 4x125WRMS at 4 ohms with 12.5volts what more can you ask for. 500RMSX2 bridged.

the PC series were expensive, the PCX were not that dear..

i loved these PPI amps, borrowed my mates one a few years a go, clean and sweet, even bridged and took a beating from 2 12's

My PPI PCX480 was running a 2ohm bridged load (1 ohm per channel) it loved it.
I paid $1100 flat from memory for the PCX480 in early 2002.
I love the PPI I ran it for a few hours running my Focal 165k's and I can tell you that the 80 watts from the PPI is ALOT different to the 80 watts from the MRV-T320 that was running them. I think that the 80 watts may be slightly underrated (you'd thinkso concidering its foot print in comparrison)

i know my PC450 was $1200 in it's day, and that was regarded as a better amp (and damn i loved it!!!)

Do you still have the PC450 I remember we talkied about this at blankys I cant remember if you still had it or not?

http://www.caraudioaustralia.com/forums/in...showtopic=59837

yep, thats the one...
but i also read a slightly less favourable review from another site...
so I'm undecided... (and who says u can trust either or none, etc)

PPI PCX
Zapco 1100.1
E-Audio 3000D
Phoenix Gold 1200.1
are the ones i would suggest you look at. All good amps IMHO

I have an MRD-M1000 and its a great amp so i might suggest the 1005 too

why yes i do

(and know where it sister is to )

personally, i would buy the amp that's required for the job. as good as PPI amps are - and i would agree that the Powerclass amps are all class - you're looking at a multichannel amp to run a sub - not ideal.

i'd suggest looking at a good monobloc for your needs. if it's of similar quality, it should have the extra balls to make it a better subamp.

I was only looking at it because it was available in the F/S and because of the high damping factor (someone will surely flame me for saying that) but mostly because it can do 500WRMS into each 4Ohm voice coil. Which I would assume would give it excellent control and SQ.

Dampening factor is @ 4 ohms per channel not 2 ohms per channel which is what a 4 ohm bridged load effectively is.

If you in it for dampening factor run the subs @ 8 or 16 ohms better dampening factor that way

In all seriousness though dampening factor on a sub should be the least of your worries. get a good quality sub and the residual EMF wont effect the dampening at all. Well IMO any way.

As shiny said Multichannels can drive a sub but you'd be better off with a Monoblock they are (generally - although I dont know of too many for in car use that arnt) designed for Sub use - have LOADS of smaller caps and MASSIVE power supplies can generally drive a fairly low load and in all seriousness the dampening factor at the lower impeadance will actually be better than a bridged amp. Bridged amps will never be as good as bridged amps when compared to them being used as multichannel

dont forget boston gt28

Yeah that too

Sorry Mr. Boston

Yes thats right, i used to like 2 channels for sub use because of their versatlity in using that amp for something else.. but for proper SQ it must be a monoblock run at no less than 4ohm.. i had to get the best for around $1500 and that was the zapco 1100.1.. poops on the PG amp i tried both.. Damping factor is important in controlling the sub at speed when a big bass note hits.. Zapco is flawless

Hmm.. well I cant get 4Ohm total, cause my sub is dual 4Ohm..

Therefore it gives a 2Ohm load and damping factor would half. The Zapco is rated at >250 @ 4Ohm.. (so it would be >125 @ 2Ohm)..

The audiosystem F2-500 is a 2channel A/B class, and damping factor of >400 @4Ohm... and therefore >200 @ 2Ohm.

Does that suggest the AudioSystem is a better amp in this application?

This suggests that the AudioSystem has the better dampening factor... That's all...

Link on dampening factor and how it's not the be all and end all here:
http://www.classic-audio.com/marantz/mdampingfactor.html

good read (helps pass the time at work - if only I wasnt so busy :s).

I think the Audiosystem still had fairly good specs for the rest of the parameters too though.

Back to doing more research

With specs for amps, you should check if the specs you are reading are "A weighted" or not. I know zapco specs are raw, which is good. But when Amps show their specs as A-weighted, they fudge them to look good. Not suggesting Audiosystem is A-weighted, im not sure at all.

if your Sub is DVC 4 then you could wire it to 8 ohms if you are that worried about dampening factor. I think that your reading specs and going with your ears. Think about it you seem to want alot of power yet you want a great dampening factor. one will essentially cancel the other out I dont give a crap how good the specs are. as stated above there are alot of "a" weighted products even from reputable dealers this isnt designed to give an advantage marketing wise its more because there is no normality.

Iceman - where abouts are you located? Ive got a 4x80 PPI pcx480 Im located around berwick area shoot me a PM I'll whip the 480 out and you can demo it in your setup if you like you can decide if you wanna go the pcx4125. But in all honesty I think you are looking at the wrong specs and paying too much attention to the wrong specs for the SQ your after.

He's after something that'll primarly feed his sub over 1000wrms... But would prefer it to be class a/b and have a dampening factor > 200

Oh and it has to be around $700ish, not much over

haha.... damnit fury... next ull be telling me what I want for dinner.. (and getting pretty spot on too ...spooky :huh: lol)

Yep thats pretty close... but maybe I am not understanding correctly, as u say Komodo. I would like to have a listen to a few amps... but not always possible.. and I cant justify spending over $1000 on an amp really... maybe I'm making a mistake if I dont... once again... I'm still learning.. but I dont want to learn the expensive (read: wasteful) way... would rather buy good quality if its a little more.. than be sucked in to cheap/nasty but 'good on paper/irrelevant specd' gear..

I have been tryin to avoid being sucked in tho... thus the research

Well if you want ive got the PPI PCX, The Alpine MRD-M1000 & a Audison VRx1.500 let me know if you wanna demo them

Wow Iceman i would jump on Komodo's offer of trying out his amps.. He is being quite generous here, they are all very decent amps.. Maybe 500watts is all you will need, let your ears decide.. You would save some dosh too

Comin in L8 here but on the subject of damping factor, the hammer has got the goods, and theres 2 for sale in the forums. meh it's only money
http://www.advanceae.com.au/catalog/produc...roducts_id=2213

Hype> yeah i totally agree.... wicked offer thanx Komodo

I had it running off a PG Xenon X600.1 (600RMS) but it was too weak.. even took it to central car radio.. and they agreed it sounded way too soft.

Komodo>I might take u up on that offer.. at a mutually agreeable time/place.
Would appreciate that heaps mate.

I know about the Hammers.. but the one i wanted H1 is sold.. now only a SH1 left.. and I'm not made of money.. :S

Just noticed... Komodo is in NSW... I'm in VIC

LOL nah im in Berwick - Victoria
Ignore the stupid side thing its homosexual.

Hahahah... ok cool!

talk about mood swing ...lol

I'm keen to try out those amps mate... my car has no stereo atm.. :/ .. but i still have the sub in the box.. so I could demo it.. purely from a power/specs point of view.. rather than installation if that suits.

sure what ever suits you - shoot me a PM and we'll discuss further on MSN if ya want

wow, that surprises me. i always considered the xenon monoblocs to be really gutsy. and i would not have considered the eclipse Ti to be a difficult load to drive; no more so than other dual 4ohm subs like an IDMAX, G5, DD, etc.

if you take up Komodo's offer, i'd be interested to hear how it sounds off the alpine monobloc. cos i was going to suggest looking at the MRD-M605. whilst it's 'only' rated at 600WRMS @ 2ohm, surely this would be enough for normal daily use. only if you were competing at SPL comps should you want more. whilst it's rated similarly to the PG, it's power delivery is not so 'regulated', which could impact on performance, not sure.

I agree shiny....

I'm not sure why it was that way.. neither are central.

We tried an Audiosystem F2-500 on it.. was much better... but only a brief listen.. so I couldnt judge the SQ difference or anything else.

Its a 750WRMS sub... but surely not too inefficient.
I've been told they can handle about 1300WRMS.. and seeing as I'm not an SQ purist... I dont mind the occasional DOOF over SQ. So I do want to get the best outta the sub (from all Ive heard about them.. they are awesome).. now I just want to 'hear' the sub actually sounding awesome itself .

The lowest I'd go is a MRD M-1005 (1000W @ 2ohm, but thats at 14.4v).

So hopefully test Komodo's amps and get some auditioning done

and you can also listen to the boston GT28
ill see what else i got lying around

we live not far from each other
so add me to msn too
and we can set up a date
hehehe

Komodo and Blanket Pm's sent...

This is sounding awefully like a matchmaker site


EDIT: I gotta log off... chat to you guys tomorrow.. cheers

thats only cause blankey loves a bit of man loving action *raow* [/me claws]

i got 2 other amps we can throw in for comparison too

a DD M1 and ohh hangon, the other one will only do 4ohm..

i got a M1

oohh ohhh add me to!!

can you bring some boobies around and we will make a party of it!!!

Boobies

Add me too!
Just for the mix we can add a Jaycar 4x100
760wrms to ur sub, probably the weakest (and cheapest) of the lot

Add me too with a Burning Desire II...

But as I have already told iceman, I am running 2 x 10" Eclipse Ti they are every accurate but do not go nar as loud as what i was excepting

I was first running them at 0.8ohm, now at 3ohms box size is about 1cf

This is sounding very much like the Sub comparison test day.
Maybe we could do something similar....

(but with boobies too )

Where we gunna do this ?

I'll offer my place - but i do live down a bit of a dirt track so probably not the best place to do it. but the offer is there