PLX amplifier mod

[thylantyr 10+ year member]

Check out my latest mad idea ..........

I think I can execute this idea in a timely manner .....

http://www.caraudioforum.com/vbb3/showthread.php?t=235343

Click to read more...

 

[ballstothewall 10+ year member]

Is it possible to know TO much about electronics and audio thylantyr? If its possble, I think you do, //content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif.

But from what I understood, I don't see why it won't work, and sounds like you sure know what the heck your doing. I demand pics and reviews once it is done!

 

[btnhfan 5,000+ posts]

I read it, and bottom line, you can play the amp at lower imp right?

 

[adio 5,000+ posts]

ur a beast

 

[thylantyr 10+ year member]

The main reason for doing it is --> because I can .. and .. I like to drive

the amplifiers lower than recomended 'ohms load' ... and it's general knowledge

that when you load down a power supply the ripple/noise increases so extra

caps would be nice for abnormal operation of the amp to keep the rail voltages

clean and help to minimize sag on transients.

I'm getting in a few more PLX's later this week, I will probably tear one

down to examine the idea more closely but I don't see any issues.

Steroid'd PLX3402

 

[joetama 5,000+ posts]

I take it you dont like Crown.... also know as CLOWN Amps....

 

[thylantyr 10+ year member]

I take it you dont like Crown.... also know as CLOWN Amps....

Crown is cool but lets compare;

Entry level;

Crown XLS - that famous 'Crown sound' one reviewer said, unbeknownst to him

C-Audio designed the amplifiers then Harmon bought them which in turn owns

Crown and next thing you know, Crown has a new XLS line of amps... /rofl

XLS is a good amp for HT because the price is nice and the sweet spot is

the XLS402, for about $250 ... see pics;

http://home.pacbell.net/lordpk/proamp/Crown_402a.JPG

No real heatsinks used, no variable speed fan, and the two fans runs high speed irritating people who own them for home use.

QSC entry level -> RMX

http://home.pacbell.net/lordpk/qsc/RMX2450-1.JPG

.. cost a little more, but you get real heatsinks in a wind tunnel design,

variable speed fan {1 fan!}, more power and the ground collector

design allows the transistors to be shorted to the heatsink with

no insulators, better heat transfer. {PLX does the same thing but different,

took me a minute to figure it out}.

Crown CE series {except CE4000 which is unique},

CE1000 and CE-2000 are nice but look ---> it's a 3RU chassis and the

CE1000 is limited to only ~2kw... QSC RMX2450 is 2RU @ 2400w ...

Crown cost more too! Given today's technology, 3RU isn't popular

for 2kw and under.

Crown XS series? Street price $1100.. I'm not sure if this amp has SMPS

or not, they don't say anything so I assume no... QSC PLX3402 has more

power for $100 more and you get SMPS.

Crown Macrotech? These are old school monsters, very nice, heavy as

a fvck... Touring amps and this classification cost alot more... I like

their 5k model, nice amp, 88 pounds. About $3k new ? QSC has nothing

to offer in this power range unless you count discountinued product //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

Crown Micro-tech ? Lets see what Crown has to say about these amps;

http://www.crownaudio.com/amps.htm

The chart has no blue check marks ... ROFL .. good for nothing ? /// hahaha

Crown K series ? This is a nice series, fanless, efficient.. very nice and

people love them for subwoofers. Limited to 2500watts, probably in

the same price range as PLX3402.. But the designer claims he'd never use one

for mids/tweeters, only woofers. it's a mixed review for the top end, maybe

50/50... PLX on the other hand has 99% positive reviews to run this amp for

tweeters/mids, but 50/50 on subs... ROFL... I can know why it might get a bad

rap for subwoofer driving. A.) power cord is IEC 16 awg .. LOL .. users recommend

IEC 12 awg... B.) rail capacitance is anemic {2X less than PL2 series}, 7X less

than my mod //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Crown I-tech ? These are sweet. 8kw in a 2RU size for $7500 street price.

/sick.. their flagship new touring amp... /sick

What about QSC PL2 series? These are nice but it's a PLX with 2x more rail

capacitance and voltage/current monitoring with dataport, rail voltage slighly

higher for a few more watts... Precision gain knobs. Nice amp, but for home

use there is no need.. PLX is fine amd cheaper.. There are tons of them

sold in the past 10 years making them a classic.. I've been buying them

on the used market, average price $770 plus $25 shipping.

What about QSC PLX2, a new product line coming soon ? This is a funny

amp.. You take the PLX famous design, make a new chassis, add more

rail capacitance, remove the rear dip switch in favor of something more user

friendly and add a crossover. Viola'... PLX2 is born... Rumors -> big price drop!

....

Best bang for buck ~2kw amp -> RMX2450

Best bang for buck ~3kw amp -> PLX3402

my cap modded PLX3402 -> //content.invisioncic.com/y282845/emoticons/yumyum.gif.0556df42231b304b9c995aefd13928a8.gif

Wildcard -> Behringer EP2500 if impedance load is light.. [RMX2450

clone with smaller ******]

Think about system design rather than 1 uber amp.. For instance,

what can you do with a $3500 amp budget ? You can get 1 Macrotech

5kw monster. Or, I can get three PLX3402.. I can do more with six

amp channels vs. two amp channels in a fully active speaker design.

Or... I can get 11 EP2500's... or 8 RMX 2450 ... etc.

Depends on application.... I like the idea of using ten PLX's for $8000

to give me 34,600 watts over an Itech-8000 for $7500. What will one

two channel 8kw amp do for me ? It will save me space, 2RU vs.

10 x 2RU ... but the Crown won't do crap when I need to drive

a 3 way active system with just two channels....//content.invisioncic.com/y282845/emoticons/crazy.gif.c13912c32de98515d3142759a824dae7.gif

 

[thylantyr 10+ year member]

Capacitor module 'sneak peak' prototype pic.

http://home.pacbell.net/lordpk/temp/plx.jpg

 

[thylantyr 10+ year member]

The pro audio folks fear my mod //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

http://srforums.prosoundweb.com/index.php/m/100424/11691/0///9947/?SQ=069a12acfa30ccddc100d040523b1ac5

.. Too many guesses as to what might happen.

This is what will happen.

A. The amp doesn't blow up.

B. The amp blows up.

All you do is make a prototype before production run

of pcb's.. pretty simple test... *coming soon*.

** throws the frankenstein knife switch ** .. lights dim,

music plays... then there is the ........... F E A R .. of

what might happen ... a time bomb ... ROFL ...

 

[DiamondFanatic 10+ year member]

Where did you learn all of this stuff? Would you mind pointing me in that direction? I want to learn more about two major things at the moment, SQ system setup and tuning for CA, and amplifier design...

 

[thylantyr 10+ year member]

Where did you learn all of this stuff? Would you mind pointing me in that direction? I want to learn more about two major things at the moment, SQ system setup and tuning for CA, and amplifier design...

Hard to explain. Maybe an analogy.

Your friend goes to music school and knows alot after getting his uber

degrees. You on the other hand focused on what you really like, guitar

playing. After your friend finished school and hung out to jam on tunes,

you realized the he svcks at playing musical instruments because he had

his head stuck in book too much and no hands on experience.. How do you explain this?

It's a balancing act. You need to spend some time in the books and some of the time

working with the hands.

//////////////

Edit ----> nuked

 

[joetama 5,000+ posts]

Damn dude, you're about as addicted as I am lol. I was raised in my family business which was a you guessed it sound and communications company. So, I got all the junk that didn't work and fixed it for me to use. So, I was bit by the audio bug at an extremely early age lol....

 

[thylantyr 10+ year member]

If all goes as planned, year 2007 I will have the system running. The plan for 2006 is

to finish the homestead projects including A/V room {nothing fancy},

mod all those PLX amps, design/build my custom AV cabinet to hold those

amps and sources, take a summer 1 month vacation to chill .... and try to

get the remainder of the tweeters for the project. The next big obstacle is

to get some metal working done, actually re-done as that project worked out

in the end, but wasn't what I wanted in the first place - arg.. more money down

the drain..

 

[thylantyr 10+ year member]

I really goofed by posting this idea on the pro audio forum. I thought for sure

they'd understand because they like this gear, they use the gear, they understand audio...

but I guess I gave them too much credit, they too are

brainwashed just like estoeric home audio people can be... /weird

http://srforums.prosoundweb.com/index.php/m/100624/9947/?SQ=f493d117f8f6afef6d4e0fac7b143027

Some of their comments are just retarted. There is only one or two people

on that thread with skill in understanding, but they still don't understand //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif... perhaps

their heads are stuck in books too much .... or lack of ...

What is the most comical? I've been trolling audio forums for years and years

and oddly enough, the one industry that gets the least amount of audio respect

is the car audio industry.... but yet, when I preach my madness on car audio forums, most of the people can

relate to the concepts in some way or another, keep an open mind.

For home audiophile forums, it's too difficult to remove what they've been taught

by reading stereophile type of magazines and what not. I was expecting the

pro audio folks to be more knowledgable, but they too have their own

audiophile ways and behavior. Interesting though, is certain car audio celebrities

[you know who they are] that have put their name on the line to break all the

audio voodoo that spreads like wild fire in those other industries. Moral of the

story, you can learn alot about audio by hanging out on car audio forums,

but the home/proaudio people will rarely agree... //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[ramos 5,000+ posts]

Gotta love voodoo acoustics. And those that sware by them //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif