[maple leafs]

I have to buy an amp to add to my Yamaha rxv-1400 receiver.


I read hear someone else added a 200 watt amp and absolutely noticed no difference in low level dynamics. It was only when they went to a 500 watt there was a perceived difference in headroom. I didn't plan on buying this much power, although after reading about the favorable price per watts one can get with pro audio it is crossing my mind.


Do you think one needs to go to this high power when adding to a typical mid level receiver to actually hear any real difference in normal listening levels?

 

[RCbridge]

Unless you have a very large room with speakers that have a low sensitivity rating NO!

 

[dsmith901]

If you always play your system at low levels I doubt you will notice a different going to a 200 watt separate amp. But if you want to play at close to reference levels then you are not just concerned with low level dynamics, and I don't doubt you will hear a difference with 200 watts over the receiver amps. The efficiency of your speakers are important also - if you have 98 dB sensitive speakers then the Yamaha is probably all you need; but if they are 89 dB (and especially if 4 ohm) then the separate amp should make a clear and audible improvement.

 

[tubeguy44]

also remember that a speakers impedance rating is it's "average rating".... the impedance can dip much lower at certain frequencies.... (and receivers are very poor at handling low impedance loads - generally)


an 8 ohm speaker can have dips as low as 3 ohms and a 4 ohm speaker can dip down to 1 or 2 ohms....


when looking at separate amplifiers..... look for the 4 ohm rating compared to the 8 ohm rating..... better amps will "double down"... that is 200 watts @ 8 ohms and 400 watts @ 4 ohms.....


cheers!

 

[Staged]

I may be one of the people you are talking about.


When I went from a SR7300 using the internal amps to an Adcom 7807, I could not hear ANY difference until I turned up the music to unreasonable levels. Not entirely true, I did hear more HISS/HUM with the Adcom.


However, when I put a RMX2450 to the pre-outs of the SR7300, I DID hear a difference. Some recordings didn't sound different, but some did. Some sounded very different with regards to clarity and detail at low volumes.


Of course turning it up was no contest.


When I upgraded to an AVM30, the difference changed again, in that certain recordings hid any difference, and some showed a very very noticable difference. I also picked up a Cinema Grand that I did keep for my 5 channel. The Sunfire had more detail and clarity than the Adcom, but did NOT have the clarity of the RMX2450 at any volume levels. The Sunfire to my ears and setup was more "colored" in it's sound than the RMX2450. The RMX2450 was also the quietest amp in my setup with no signal, and took more control of the speakers, esp as the volume rose. It was just the cleanest and most neutral in my setup. Again, I only tested the amps/reciever/pre amp I mentioned, but I am so satisfied, that unless someone were to bring over another amp and do all of the setup themselves, I have no interest in searching for that last .0001%, that I will probably not hear.


For the record, this was repeated in blind tests where my friend did the changing of the amps. I also used music that I was very familiar with, so I could not only listen for the details, but measure overall enjoyment at the same time.


BTW, the RMX2450 absolutely ROCKS for HT. It is UGLY and LOUD (until you disable the fan), so I hid it in a salamander rack with screen door. Looks great now!


FWIW, the upgrade to the AVM-30 was easily the BEST upgrade for the $$ to me. Remember an amp's job is to amplify a signal without adding or subtracting anything. A good amp should really sound like NOTHING, just do it's job and amplify the source, pre-amp, no matter how good or bad the signal is. It should just amplify the bad, and amplify the good. To my ears, the RMX2450 did that the BEST from my tests with the amps/receiver I mentioned.


YMMV


Best of luck.

 

[tubeguy44]

Quote:

Originally posted by maple leafs .....Do you think one needs to go to this high power when adding to a typical mid level receiver to actually hear any real difference in normal listening levels?

considering that receivers are usually over rated for real power.... yes...

http://www.geocities.com/Area51/Holl...1/ratevsac.htm



cheers!

 

[maple leafs]

Guys thanks for the replies and advice.


I suppose I should have qualified that I must make an upgrade and the question for me is to go typical 200 watt p/c power or absurd 500 watt.


(I must upgrade because the Yamaha has melted the woofer and tweeter of one Gershman (87/8ohm) and one substitute Paradigm (90ish/6ohm) within a two week period. Whether it is just a defective amp or an under powered amp clipping problem which is played normally at -15 to -8dbs as it reads, I don't know yet but I'm not taking any chances so I will add extra power after everything is fixed. Strangely enough both occurred on the same front left channel)


Anyways, it sounds like Stage did hear a big difference changing to mega power. Anyone else have the same findings?.

 

[paulbf1]

500 watts will give you 4dB more SPL maximum. Now, considering that most home speakers compress power at higher levels, you'll be lucky to get 2dB SPL out of it. If you listen to loud HT, you're at about 100-110 dB max, 2-4 dB doesn't do a lot.


The only reason to have that much power is: 1. your speaker are very inefficient (

 

[tubeguy44]

depends on your room and setup......


i think "thebland" here on this forum would disagree that 200 watts is enough.....


here is the audio portion of his setup...
Quote:

AUDIO Surround Processor: Lexicon MC-12 Version 3 Front LCRs: Servodrive SPL Runts Side Surround Speakers: Citation 7.3 Dipoles Rear Surround Speakers: Citation 7.3 Dipoles Subwoofers: Servodrive B-DEAP-32 subs (2) Subwoofer Amplification: Crown K-2 amplifiers (2) - each bridged to 5000 Watts (flat [+/- 3 db] to 12 hz / over 120 db output) Amplification for LCRs: QSC SRA 2422 (2) Equalization (analog): Rane THX 44 Equalization (digital): QSC DSP IV (3) Equalization (digital): QSC DSP 30 Line conditioning: Brick wall, Richard Gray 400 MK II

http://www.winglake.com/NHCTheater.asp?page=&pagenum=1



cheers!

 

[paulbf1]

>depends on your room and setup......


absolutely. but 200 watts for most homes is more than enough. My room is 15W x 35L x 12H and 120 watts/ch in more than enough for my LCR, LS and RS that have about 90 dB sensitivity. This is a true 120 watts for all channels, keeping in mind that most ratings on cheap receivers are rated for 1 channel only. I can easily hit levels that could damge hearing (110dB) after a few hours of listening.



>i think "thebland" here on this forum would disagree that 200 watts is enough.....


that is not "most setups"



maple leafs,


If the receiver is blowing both the woofer and tweeter, it may have a problem or your speaker can't take that much power. I'd have the receiver checked out.


Paul

 

[tubeguy44]

i agree that 200 watts should be fine....


just wanted to show you the other extreme!

 

[maple leafs]

Paul and Tubeguy, actually it is not so much that I am trying to get higher spl's, it is that I am wondering if the jump from 200 to 500 w/c will make any difference in the sound when listening at normal/medium levels. There has got to be a point when anymore current than one already has will mean zero difference. I just don't know where that point is.

 

[tubeguy44]

the big key is to have enough headroom for the very fast transient peaks which can suddenly exceed your average listening levels by 10 to 15 times...


so if you are listening at 10 watts of average power.... a peak can suddenly demand 150 watts from your amp......


some inefficient speakers or very large rooms have the average power levels running about 20 to 25 watts..... you can see by doing the math why they might require more power...... (25 X 15 = 375 watts!!)...


if you don't have enough power for the peaks the signal will clip... causing distortion and possible speaker damage....



cheers!

 

[paulbf1]

Agreed. But that would not blow a woofer unless you exceed the thermal rating (perhaps it's just a poorly built woofer or overated in terms of power handling). The crossover rolls off out of band distortion components (unwanted multiples of the fundimental tones) into the woofer so the distortion components you have to worry about are into the tweeter where there is no rolloff.


Paul

 

[avaholic]

Paul,


So what you are saying is, with quality speakers this probably a non-issue.


With all this talk about having enough power to drive speakers, I've been wondering if I needed more power. So I decided to ask someone who would definately know (about my speakers anyway). So, I posed the question of amplifier power to Phase Technology about thier PC 3.1II speakers (that I own), which are 6 Ohm with a 92dB sensitivity rating. I drive them with a 56TXi (110W x 7) crossed over at 80Hz. I was told that with the speakers having a relatively high sensitivity rating and being crossed over at 80Hz, that driving them with the 56TXi would be plenty of power without any audible effects as far as clipping or damage to the speakers. He said those very momentary peaks would do nothing to these speakers at all, and he said the peaks definately would not be audible. He said if I was driving them with one of those cheaper "100W" receivers that actually only put out about 25-50 watts per channel, then I would have something to be concerned about. He actually thought it was kind of funny. Mentioning that many companies that make these mega amps thrive on the "Tim (the tool man) Allens" of the world that always think more is better. He of course qualified his statement by saying, that high wattage amps definately have thier place. That being large Home theaters and/or very low sensitivity speakers, combined with people who want to play thier systems at or near referance levels.


FWIW: I listen mostly to music, and alot of Multi-channel Hi-Rez stuff. Listening at average levels of around 60 dB or so (but every so often up to 80-85 dB, I'm not as young as I used to be), and I've never heard any ill effects, clipping or otherwise. The imaging stays clear and focused with no audible problems with dynamic headroom or compression at all.


Since Phase Technology and thier parent company United Speakers Systems has been in business longer than I've been alive (since 1959, I think), owns several patents (including the soft dome tweeter), and has been supplying speaker companies all over the world for more than 4 decades with speaker components, I think I would tend to believe what they have to say regarding this issue!


Best Regards,

Patrick

 

[tubeguy44]

Quote:

Originally posted by avaholic ....... that driving them with the 56TXi would be plenty of power without any audible effects as far as clipping or damage to the speakers. He said those very momentary peaks would do nothing to these speakers at all, and he said the peaks definately would not be audible...... ......FWIW: I listen mostly to music, and alot of Multi-channel Hi-Rez stuff. Listening at average levels of around 60 dB or so (but every so often up to 80-85 dB, I'm not as young as I used to be), and I've never heard any ill effects, clipping or otherwise. The imaging stays clear and focused with no audible problems with dynamic headroom or compression at all.....

patrick,


you may not be damaging your speakers at all....but then again you are not hearing all the signal.....


if the peaks are cut off, then of course you won't hear them...... until you try a more powerful amp in your system you will never know what you are missing.....


if you look at my system in my signature you will see that i am running an elite 55txi (100 watts per channel @ 8 ohms) and super efficient klipsch KLF-30 speakers (102 db @ 1watt @ 1meter)..... i still use a carver pro ZR1000 digital amp to power these very efficient speakers.... (225 watts per channel @ 8 ohms)....


does it sound different than the internal amps of the 55tix???.... YES!!!!.... the low level detail is very much improved and those peaks that you say you can't hear are there with the ZR amp..... i had considered selling this ZR amp about 8 months ago when i was in between jobs, so i took it out of the system and hooked up the 55txi internal amps..... recalibrated the MCACC..... i lost the low level detail and on those fast transient peaks, there was a very noticible difference - i'm not sure if it was that the overall sound changed because the amp was momentarily clipping or because those peaks were clipped.....


and i do know that the peaks definitely exist..... a great example to demonstrate this is the telarc multichannel SACD version of the 1812 overture..... listening to the entire first track at a comfortable listening level in my room (26' x 14' x 8' ceilings) - 75 to 80 db SPL - when the cannons go off at the 12'45" mark (or so) the meters of my ZR amp hit the red led's briefly.... that indicates exceeding full rated power.... (you would be very surprised at the amount of sound in the treble region that comes from a great recording of a cannon).....


for brief instants - over 225 watts was being pushed into my main speakers..... those dramatic peaks did not sound like clipping with the 55txi's internal amps - they just sounded different.... and by switching amps i could see that the internal amps WERE clipping.....


i'm sure that on other very dynamic DVD's and multichannel music there are demanding peaks as well - probably nothing as dramatic as the 1812's cannons.... but the fast transient peaks are there.....


either your amp will play them accurately or it won't...... as many people in the pro amp thread have discovered..... adding that outboard amp (even an entry level pro amp) can do wonders for the sound and performance of your system......


and because the clipping happens so fast, there may not be a point where you can say..."ah - that note was clipped"..... but it is there nonetheless.....


Phase Technology may have been making speakers a long time.... but their tech has given you incorrect information..... who knows - maybe the tech just started with the company???......


just for the record - i am running my KLF-30's set to "large" and that will put more demands on the amp than set to "small"......


cheers!

 

[avaholic]

tubeguy,


First of all, I respect your opinions very much. I did forget to mention (though I have said it a few times in previous threads), I've tried a Sherbourn 5/1500A and did some pretty long comparisons awhile back (over a year ago), and I came to the conclusion that at my normal listening levels about 60dB or so, I could tell no difference at all, not even the smallest bit between it and my AVR. Now when I was running my mains full range I agree there were some tracks that the internal amps just could not quite cut the mustard at very high levels. But there was absolutely no difference to my ears with the speakers crossed over at 80Hz.


I appreciate your ethusiasm, I really do! But if I can't hear a difference (and it's not damaging my speakers) with my particular setup and listening habits, I have no reason what so ever to use an outboard amp.


As you say: "and because the clipping happens so fast, there may not be a point where you can say..."ah - that note was clipped"..... but it is there nonetheless....."

Again, bottom line if it's not damaging my speakers, and it's not audible, I don't really care if it was clipped. If I could hear it given my setup and how I listen to music that would be one thing, but I can't! Fair enough?


I do appreciate all your infomative posts and as I said I respect your opinions! But I've got to go with my own ears here, not anyone else's.


Best regards,

Patrick

 

[Carl Brinkman]

Patrick,


If you are satisfied with the sound quality of your reciever compared to the Sherbourn amp then just get the reciever fixed and thouroughly tested out and be done with it. Your fried drivers are NOT likely due to the recievers clipping at the sound levels you are listening at.


For most folks the decision to get a seperate amp in liu of a reciever is based on the QUALITY of the sound, not the power. VERY few high-end amps have anywhere near 500 watts. Since you have already tried out the Sherbourn, which is a pretty decent middle of the road HT amp, you already know you aren't likely to hear a difference unless you spend serious money. That would be silly in your case.


You don't show your location as that's important. Not every "authorized repair facility" has the capability or desire to really troubleshoot the electronics for your type of problem. When I lived in the middle of the Silicon Valley I had access to some of the best electronic designers around. Since I moved here a few months ago I don't exactly know where I'd go with your problem.

 

[maple leafs]

Carl, so there is no confusion, I'm the one with the underpowered (or was just unlucky and possibly got a faulty one) receiver that fried the two speakers. Avaholic is responsible for the 2nd and 4th last posts.

 

[tubeguy44]

patrick,


i hadn't realized that you had tried an outboard amp in your system earlier.....


cheers!