AVS › AVS Forum › Audio › Receivers, Amps, and Processors › New amp is making me grin from ear to ear =)
New Posts  All Forums:Forum Nav:

New amp is making me grin from ear to ear =) - Page 5

post #121 of 4947
Quote:
Originally posted by spider_bill_2003
You just had a bad connection with the adapters. However, I prefer to use the method with the fewest mechanical connections, so a custom (or standard) cable would be the preferred connection method!

--Bill


I would agree with the fewest possible connections, as to adapters degrading the signal, I have no idea. But for my own peace of mind, I want the least breaks in a signal I can have.
post #122 of 4947
Quote:
Originally posted by SRR
bartman_451,

There is nothing wrong with running the dials on the amp at full so you will get a 100% repeatable volume evey time you turn them on, in fact this is the preferred way to run amps.

I agree completely. If need be, before powering down everything, reduce the source volume. That, IMO should eliminate the audible thump, or at the least reduce enough to not matter. I had a Soundcraftsmen PM-840 that thumped at power on, and this method reduced it quite a bit.
post #123 of 4947
Quote:
Originally posted by SRR
Ok either the adaptors you were using introduced nosie or not, the speakers you sold would revel that noise just as well as any consumer speakers would...your not making much sense here. Did you try the speakers you sold with your adaptors in the chain??? lol .


i'll try to type slower so you can understand.....

my klipsch KLF-30 speakers are much more revealing in terms of detail and response than all of the Electrovoice, JBL, Peavey, Community, EAW, or Yamaha speakers that i sold....

my customers did on occasion use adapters in certain situations.... in those cases with the amps that they were using they did not notice noise added to the signal...(at least no noise problems that they reported back to me).... whether due to less sensitive speakers, preamplifier issues, amplifiers running in the 70 volt mode, or just general background noise in their installations.... generally my customers would avoid adapters unless there was absolutely no other way to solve the problem.... just for reliability's sake if nothing else.....

so yes.... it is possible with your experience in pro audio that you never noticed any additional noise by using adapters....

i did notice noise in my system with the adapters in the signal chain.... i took them out and replaced them with a soldered cable and the noise went away.....

did i type that slow enough for you to understand???
post #124 of 4947
well..i buy cables from a guy i found on eBay. He just made me 18 custom cables for like $84 shipped. XLR to RCA...thats something like $4.60 a cable. at least i htink it was 18...it might have been 12 cables...but still..thast a lot cheaper.

PM me if you want his name. they are good cables too!!

edit: here are the cables i got from him.
6 - 4 foot XLRM to 1/4 phono TRS male cables
6 - 3 foot XLRM to RCA male cables
6 - 4 foot XLRF to 1/4 phono TRS male cables

and it was $82.25 shipped. So thats way cheaper!
post #125 of 4947
Typeing slower doesn't help at all the transmission speed of the internet is the speed of light minus all the routers it went through to get here, so its obvious typeing slower doesn't help me one bit. hehehehe

On to the task at hand...

Your saying that the studio monitors I used weren't reveling enough to here the degradation that an adaptor introduces, and I am sitting here telling you there is no possible way that could be true...I think we are at an inpass.
post #126 of 4947
Thread Starter 
Could we move the bickering about adapters to another thread?
post #127 of 4947
The Crest CPX series are similar to the Crown XLS. These are 'budget' pro amps.

I went with the Crest over the Crown due to better specs, plus on the recommendation of a pro audio 'pro' friend.

My Crest has 'soft on' so no problem with thumps. It also has a 'soft clip' feature which automatically cuts the gain at clip levels. Built in sub crossovers are also a feature.

For those who buy based on lbs. per dollar, my Crest has 20 pounds on the similar wattage Crown.

Don't get me wrong, I'm sure the Crown rocks the house. But I'm very pleased with my Crest.
post #128 of 4947
Well, I took the plunge and just bought the Crown on Ebay. Going to give it a try on my fronts and decide if I want to keep it and get another for the center channel. I'm sure the Carver is a great amp but 2 will set me back almost $1,600 vs. $500 for the Crowns, and since I haven't ordered/paid for my Axioms, SVS sub, Samsung 941 DVD player or Denon 3805, it was a good choice!
post #129 of 4947
Hmm, the best I can find for a new Crest CPX 1500 is $400, whereas a new Crown XLS 402 is going for $300.
post #130 of 4947
Quote:
Originally posted by SteveCallas
Hmm, the best I can find for a new Crest CPX 1500 is $400, whereas a new Crown XLS 402 is going for $300.

You can get the Crown for less than that on Ebay, new in the box. $229, plus shipping in my case.
post #131 of 4947
Damn, thread has grown pages while i was at work..I'd say let's put the adapter issue to rest guys..I agree less breaks the better! that is a FACT.but, i'm using adapters on my first Crown and when i put my ear to speaker it is dead quiet!!For these other 2 amps i will be using XLR to RCa cables..Think I paid around $7 per cable in 5ft length which was about same pice as my adapters, which I love!!The ones I use won't come loose form Amp..They "click" lock to it.I electrical taped my rca to the adapter so hopefully this won't come loose either.

Also, if you want the BEST price on the Crown, then you need to look to Ebay.Under $270 shipped all day..Remember folks, Crown has a 3yr no fault warranty.So it will be fixed if something goes wrong and let's say seller has left ebay..Just my take on it.

For me,I'm just glad to see so many guys at least TRYING this amp out.I hope your results will be as good as mine!I can't wait to see how my rack is gonna look with those 3 amps sitting in there..Just checked,will be delivered on Friday unless UPS mucks up..

I looked at the QSX rm850, but went with Crown for power and price..Each slightly better thru Crown..The only thing I worried about was the weight..I think QSC has more..But hey, Bob's Sunfire reciever is almost half the weight of say a Denon 5803..Can we say almost double the power..Just saying there's so much to factor in the buying decision.Whatever you do, look at ONE OF THESE before you drop $$$$$$$ for the "big name"!

Damn almost forgot about the "thud" issue..I'd agree with the poster that said just turn all knobs to 100%.This is most definitely the easy way to solve the remembering my levels problem.The receiver(pre/pro) is controlling master volume anyway.Also my Pioneer has a soft start to it so if amps are up, it's not the instant thud anyway..Just not as big deal as it may appear to be.

brickie
post #132 of 4947
Quote:
Originally posted by bartman_451
HI
Sorry to be such a newbie when it comes to pro amps, but am I correct in assuming that the auto-mute feature is what prevents the "thump" from passing through the speakers? This is a major consideration for me; I'd rather not have to manually set the levels every time I power on; I think it would be hard to calibrate things as closely as I have it calibrated now, even if I mark the spots on the dials, since these amps have so much power.

So what pro models don't make a thump? And has anyone done an A/B comparison with the so-called "audiophile" amps?

Thanks!!!!
Bart

Well, it depends on the model, some have the mute feature and some don't. Also, many have detented knobs, so you can count the number of clicks when you turn it.

I personally would suggest not turning it to the maximum, because then you'd reduce your input signal pretty low otherwise it would be too loud. You really would want your input signal to be the nominal voltage that the amp is expecting, somewhere around 1V or so depending on the amplifier.

As far as A/B comparisons, the "Home Theater Amplifier shootout in MN" thread has a Lexicon amp that fared well. It is a Crown built amp. Of course this is a higher end product, but shows that pro companies can build comparable amps.

There is another comparison I'm aware of, but it was a private test, and in that one a "audiophile" amp and a pro amp were pretty close. Of course both of these retail in probably the $2000 range.
post #133 of 4947
I understand all the specs..for the most part anyway.But what I like about pro amps is the power!And there is alot of it!!! I was always taught that MORE power = a much cleaner signal and sound..Yes,i'm sure theres other factors to that..I think when all is said and done, many will be surprised by these amps.

brickie
post #134 of 4947
XLS 402
260w @ 8 ohms
400w @ 4 ohms
570w @ 2 ohms

Lets say you can get four of them for $1100, that is an eight channel
HT amplifiers that is 2 ohm stable. I'm sure the fans will turn on with
a 2 ohm load, maybe with a 4 ohm load, but where else do you get
>4KW of power for 25 cents per watt

I'm not sure why an HT setup would taxi even an entry level pro audio
amplifier assuming you have small surround speakers, etc.

I've been downloading service manuals (schematics) of these entry level
pro audio amplifiers to check it out, but I can't find Crown manuals for free
and Crest I need to call.

QSC, Yorkville, and Carver ZR I got from their website.

The Carver ZR series uses the Tripath chip (class T) and their schematic
looks like the Tripath reference schematic except Carver has a more complex
output filter and of course they have more 'stuff' on the input. Like may
'digital' amplifiers the output stage doesn't have redundency, only one
pair of transistors per channel. This is because efficiency is higher. The
schematic also indirectly indicates that it's the same circuit design may be
used for all ZR models with the only difference being the power supply,
probably the toroid, filter capacitors, and fuse. I'm not sure about heatsinks
sizes.

For the electronics phreak -- if a ZR500 can be had for $400 and if the above
is true, this amplifier might be 'mod friendly' to allow it to operate like
a ZR1600. Is there room in that ZR500 chassis to stuff a big fat transformer,
perhaps 2KVA... /lol/.... ZR2000 - hehe
post #135 of 4947
post #136 of 4947
I would agree with what you said..These amps are not for wimp speakers. I believe all the reviews for them so far have been using Polk speakers..Which i love and own!!! They really wnat and need all that power!!I'm sending at least 400 solid watts to my rt3000p's!!!!They're rated at 500 watts per channel. Looking over a review of them in Home Theater mag, I believe it said they dip below 4 ohms, with my center actually running below 3...they need and want all this power!

brickie
post #137 of 4947
My 5-channel Adcom amp has gains for all 5 channels, and the Adcom manual says to make sure all of the gains are at MAX level at all times and leave then there. I plan on doing the same w/ my Crown amps when they arrive. Let's not make this any more difficult than it has to be.
post #138 of 4947
Using pro amps in a home isn't anything new as this thread would seem
to indicate. There are many people that do this and many bypass the
fans because they don't abuse their sound system and they don't have
any abnormal loads to drive.

If you look at history the dollar per watt is getting better in both the car audio
and pro audio industry, but the exotic home audio industry won't give up their
strangle hold and they insist on selling at high prices. I wouldn't even bother
buying exotic home amplifiers unless I had some crazy load to drive, maybe
1 ohm or less per channel.

Study amplifier design and you will notice there is no fundamental difference
between an amplification stage used in car, home or pro audio. I know
that pro amps have smaller heatsinks, this allows them to pack their power
in that standard sized chassis and this forces them to use fans to dissipate
the heat.

Hypothetical;
You can take any pro amplifier design and use this same design and
sell it as an audiophile amplifiers and charge alot more money. To
make this happen, it's easy. A few modifications.

1. The designer takes the pro amp and guts the signal processing, ie,
removes electronic parts.

2. The designer will use bigger heatsinks in a 'normal' sized chassis.

Viola' , now you have a audiophile home amplifier that is 4 ohm stable
and all you did was remove parts and add more metal. /hehe

Do you want it 2 ohm stable ? Then upgrade the power supply transformer,
spend $50 - $100 on the upgrade. Next, double the output stage transistors
and reweak the predrivers. This will cost under $50.

Cool, now you can charge 5x - 10x more that the original.



post #139 of 4947
I'd put on your flame suit, buddy...cause a lot of people aren't going to like that!

(I'm with you though....hehehe)
post #140 of 4947
I like talking about audio voodoo. It goes against the grain.

There is a memorable moment on the DIY forum where Nelson Pass
posted schematics of an old highly regarded Krell amplifier (old school).
You know these amplifiers have sonic magic inside right ?

The locals on that forum were amazed to see a very simple circuit
design (20+ years old), a topology that is so bare bones that no
circuit designer today would even consider using --- yet, it's a great
sounding amplifier...

What made these amplifiers great was the power, the beefy output
stages to drive low impedance loads, the large heatsinks, etc.
Because it was able to do it's job well, naturally is sounded good
whereas a weak amplifier will sound bad not because the sonic magic,
but it fails to do it's job at amplification. /hehe
post #141 of 4947
You brought up a good subject that has been mentioned..removing the fans.Do you really think this is safe to do? In speciifc with these 402's? Even if you play your system at reference of close to it ? I know these are built like tanks.

brickie
post #142 of 4947
Quote:
...I'm sure the fans will turn on with a 2 ohm load, maybe with a 4 ohm load....

With the XLS Crown's, the fans are on all the time.
post #143 of 4947
The generic rule of thumb is. Amplifiers running less stressed generate less
heat and you may get away with running with no fans depending on the
load. This is trial and error. You have to monitor the heatsink temperature,
finger test .. /lol

If there is too much fan noise especially if you buy an array of these pro
amps, then I can think of a few mods from simple to complex, depends on
your skill level.

1. If you don't push the amplifier hard you may be able to operate the fans
at a lower speed by inserting a resistor inline with the fan to reduce the
voltage at the fan, causing the fan to spin slower, less noise. This requires
trial an error until you find the right resistor value.

2. You can replace the fans with low noise fans (wind noise). Usually
lower noise fans are lower CFM, but there may be enough flow for
adequate cooling. This is the least damaging mod because it looks
stock whereas the other mods resemble 'monster garage'.

3. You can add a toggle switch (to the front panel?) to turn on/off the
fans at will. You need some electrical skill to do this.

4. I like this one. Build a fan speed control circuit and install it somewhere
inside the amplifier. Add a 'heat sensor' to the heatsinks and let the fan
operate in low, med, high depending on heat produced.

5. The uber_poor_man mod. This sounds sick, but may work. Cut a piece
of thin cardboard and partially cover the fan intake vent (or exhaust).
I did this with my noisy computer chassis fan, I didn't need a high flow
fan and just taped a piece of paper to cover it partially. Less noise, decent
air flow. /lol/
post #144 of 4947
SRR is right....

the fans on the XLS amps are always on.....

but if you do a little searching you can find low noise fans to replace the stock fans.....

the crown fans are definitely not as loud as the stock fans used in qsc amplifiers..... qsc makes a very good amplifier, but they seem to have found the loudest fans that they can...

silenx makes very quiet fans.... although i believe that they are 12vdc only.... (most pro amps use a 24vdc fan)... if you remember your last electronics course, you can use a resistor to drop the voltage from 24v to 12vdc and allow the use of a 12 v silenx fan in your amp....

another brand that offers a quieter fan is "pabst".... (just like the beer).... they offer fans at 24 vdc as well as other voltages.....

you could also use a quiet fan from middle atlantic that is 110 vac.... i used one and mounted it externally on a qsc amp... the fan was about half as loud as the stock qsc fan.....

if you go with the carver pro ZR route, the fan can be "safely disconnected"....(quote directly from factory tech support)

there are options to address the fan noise issue.....

cheers!

post #145 of 4947
/joke

George Carlin meets the Audiophile

If an particular amplifier sounds better than the rest, why
don't they just clone the dang thing ?

Ever notice that anyone playing louder music than you is an
idiot, but anyone playing lower than you is an audiophile?

Why do people burn in their amplifiers to improve the sound?
How do electrons know that you want better sound and not
worse?

Does a tone deaf audiophile say the amplifier sounds bright
after regaining his hearing ? Or was the amplifier an innocent victim ?

How come nobody says "It sounds bad" after doing a major
equipment upgrade ?

How does an amplifier know if the music is a complex
music passage and it needs to take extra care to please you?

Last night I played a blank CD at full blast. The audiophile
next door went nuts.

If 4 out of 5 audiophiles suffers from psychoacoustics
.... does that mean that one enjoys it?
post #146 of 4947
Quote:
4. I like this one. Build a fan speed control circuit and install it somewhere
inside the amplifier. Add a 'heat sensor' to the heatsinks and let the fan
operate in low, med, high depending on heat produced.

it's already been done for the electronically challenged out there....

http://www.middleatlantic.com/rackac...cooling.htm#fc
Quote:
FC Series Thermostatic Fan Control

The Middle Atlantic Products proportional thermostatic fan controller extends equipment life and reduces service calls by varying the fan speed of up to four fans based upon temperature. The fan controller has 3 temperature ranges and can be set to operate the fan speed either proportional to temperature, or to come on full speed when the temperature threshold has been reached. This UL Listed device can also be turned on or off via a local switch, and includes status LEDs. The fan controller can be mounted to rackrail brackets or any flat surface, and is also available as an MPR series module and is manufactured from galvanized steel with a durable min-spangle finish. A temperature probe is provided with a 5 ft. wire. This controller is designed to work specifically with fans that are offered by Middle Atlantic Products, or other fans with similar specifications. Max load 1 amp/120 volts

here's the cut sheet....

http://www.middleatlantic.com/specs/96_980FC.pdf

they sell for about $120 new..... if anyone's interested, i happen to have one of these i am no longer using..... (i had an old receiver that ran very hot).... i'll let it go pretty cheap.....pm me if your interested....
post #147 of 4947
Quote:
Originally posted by thylantyr
/joke

George Carlin meets the Audiophile

If an particular amplifier sounds better than the rest, why
don't they just clone the dang thing ?

Ever notice that anyone playing louder music than you is an
idiot, but anyone playing lower than you is an audiophile?

Why do people burn in their amplifiers to improve the sound?
How do electrons know that you want better sound and not
worse?

Does a tone deaf audiophile say the amplifier sounds bright
after regaining his hearing ? Or was the amplifier an innocent victim ?

How come nobody says "It sounds bad" after doing a major
equipment upgrade ?

How does an amplifier know if the music is a complex
music passage and it needs to take extra care to please you?

Last night I played a blank CD at full blast. The audiophile
next door went nuts.

If 4 out of 5 audiophiles suffers from psychoacoustics
.... does that mean that one enjoys it?


Good stuff !!!LOL!

"How come nobody says "It sounds bad" after doing a major
equipment upgrade ?"

Especially this one in particular!!!!!!I call it the placebo effect!!Actually though a FEW yrs back I tried a Kenwood stage 3 setup for a few months..It was their attempt to get into the pro/pro, amplifier market.It sounded like $HIT!! I ended up going back to a reciever, and originally this amp setup was like $3000-4000! This was when I first realized that Because an item is expensive doesn't mean a thing.

Yeah those are some good ideas to address the fan issue.I'm just going to play it by ear at this point until I get all amps installed to see where fan noise stands..My skill level is high enough to do all the mods mentioned although I like the second to last best..building the fan speed circuit!May try that one..

brickie
post #148 of 4947
I have gotten used to fan noise, as I use my computers sound card as a pre, and have done so for years now. At the volume level I listen to, I do not hear any fans, and I have 8 in my comp. The fans noise level, that will be in the amp I have on the way, I'm sure will not matter to me. I do both 2 channel and well as gaming off the same system, in a room that is 11' w x 9' d x 8' h. So once the volume is up a bit, there is no noticeable fan noise. Even with the comp less than 3' away.
post #149 of 4947
I use this on my computer, although you may have to adjust the input voltage if the unit runs on 24V. Also, Panaflo fans are considered to be very quiet, the L1A being the most well known.

http://www.siliconacoustics.com/nmt2.html

I'm sort of surprised this doesn't have a variable speed fan, or does it, but I suppose it's one of the features that being an entry level unit doesn't have.
post #150 of 4947
Terrax, I agree with you completely man! Once you get this amp going fan noise will become a non issue..And i'm in a decent room, 12x22 or so.Well gotta get some sleep.I suppose when i get in tomorrow there'll be another few pages to read..LOL later guys!

brickie
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Receivers, Amps, and Processors
AVS › AVS Forum › Audio › Receivers, Amps, and Processors › New amp is making me grin from ear to ear =)