Need advise on my system

[HMT]

Hello experts,

I have a Onkyo TX-SR701 which pushes out 100W/channel at 8Ohm. This receiver is driving a pair of Polk Audio Rti70 speakers, 1 center and 2 rear each supports up to 250W continuous and has efficiency of 90db. I use it a lot (singing, etc.) and watch movies very loud (volume 70 over 90 max). Recently 2 of my tweeters went bad. I've started to read a lot and found that 90db is "kinda" low efficiency and this is why I had to turn my volume up that high. Do I need to get a separate amplifier (~200W/channel) so that my receiver won't work as hard causing distortion to my speaker? or is my receiver is way enough to drive these speaker?

If I was to get a separate amplifier (say 200W/channel), will the output to the speaker be just 200W/channel or will it be 300 total (100 from my receiver + 200 from amplifier)?

By the way do i need to get the pre-amp or amplifier?

Thanks all
HMT

[Mr Peabody]

A preamp just passes the signal and allows for volume, source selection etc. It won't drive speakers. The power amp is the part that drives the speakers.

Your tweeters blew because you were driving the receiver too hard and allowed it to clip "distort". Adding an external amp will help this. You need more clean power. By the way, 90dB is about average for home speakers, I wouldn't say it was low.

Your receiver will need preamp outputs to connect an external amp to. You will use the receiver's volume and other controls as normal because it will in effect become your preamp. You will hook the speakers to the external power amp. So in your scenario the speakers will only see the 200 watts from the external amp.

I would check Audiogon or Craigslist for used Adcom gfa-5500 or 555, these sell cheap for what they are. They will rock for you. 200x2 into 8 ohms and good bass response. If you wanted separates the Adcom preamps are crazy cheap. I saw an Adcom gtp-450 for $100.00. It was $450.00 new but even at that was a bargain and it includes a tuner, and remote. It's not "high end" but for $450.00 it was better than what I expected it to sound like. So to get one for practically nothing is.......

Another way you could go is to get more efficient speakers, like some Klipsch which go over 100dB and leave your amp as it is.

Sometimes people turn music up loud trying to make it sound fuller. Another thing you might try is adding a subwoofer to fill in and beef up the low end.

[HMT]

Hi,

Thanks for a good response and suggestion. I do have a Velodyne CHT12 subwoofer (170W) I forgot to mention. So then answer is the preout is just a passthrough and will not ultilize the receiver's 100? speakers will only get 200w from the power amp.
Sound like I either need to get a power amp or higher efficient front speakers. I've looked at the power amp and man they're expensive. Though I listen to music very loud. I've also watched surround sound movie a lot, so do I really need to get the 5 channel or just a 2 channel power amp (5 channel will cost me arm and leg if I don't really need it)? Since the 2 front spearker are the only 2 got "hit" the most, what I was thinking to do and please correct me if I am wrong (or not a good thing to do) is to buy a 200wpc 2 channel (stereo) power amp. Hook this power amp to the pre-out front left and right (yes I do have pre-out on my receiver) from my receiver so that they can push out 200W to the front speakers. Hook up the center and 2 rears to the receiver as they are right now (these 3 will on get the "original" 100wpc). Will this work? Does it harm the receiver/speakers at all? Will the sound be out of sync (being that they're not coming from the same "device").

I'd really appreciate if you can answer these questions.

Thanks a lot for your help.

[Mr Peabody]

[QUOTE=HMT]Hi,

Thanks for a good response and suggestion. I do have a Velodyne CHT12 subwoofer (170W) I forgot to mention. So then answer is the preout is just a passthrough and will not ultilize the receiver's 100? speakers will only get 200w from the power amp.

* The preamp outs isn't really a pass through, it is the signal coming from your receiver but instead of going to the internal amp it will go to whatever you have it hooked to, ie. external amp. Correct, if using a 200 watt external amp and that's what your speakers are hooked to, that's all they see.

Sound like I either need to get a power amp or higher efficient front speakers. I've looked at the power amp and man they're expensive. Though I listen to music very loud. I've also watched surround sound movie a lot, so do I really need to get the 5 channel or just a 2 channel power amp (5 channel will cost me arm and leg if I don't really need it)? Since the 2 front spearker are the only 2 got "hit" the most, what I was thinking to do and please correct me if I am wrong (or not a good thing to do) is to buy a 200wpc 2 channel (stereo) power amp. Hook this power amp to the pre-out front left and right (yes I do have pre-out on my receiver) from my receiver so that they can push out 200W to the front speakers. Hook up the center and 2 rears to the receiver as they are right now (these 3 will on get the "original" 100wpc). Will this work? Does it harm the receiver/speakers at all? Will the sound be out of sync (being that they're not coming from the same "device").

* It will work and harm will come to nothing. As long as you don't over drive it any more. For surround sound everything will be in sync, once you hook up the external amp you will have to go into the receiver's set up menu and reset the speaker levels. This may also help the amp by taking the front two channels off the internal power supply, it could make it easier on the receiver to drive the other three. I'd recommend for music just using the stereo amp. And, you like it loud, so set the internal receiver's speaker volume about half way between -0- and whatever max is. You may have to turn the fronts down when watching movies. Hopefully the receiver has a memory to allow for more than one set up. You could also remedy this by using "bypass" or "direct" mode if the receiver has one. This should bypass the decoder and internal stuff. That's probably the best way to go.

Unless you listen to music in 5.1 the multichannel amp isn't necessary. Start with a 2 channel and if you want more get another 3 or 5 as money allows. An amp will be cheaper than new speakers and you want all your speakers to match, especially the front three.

The Adcom gfa-5500 or 555 can be had for under $500.00.
You might also look at Nuforce who offers large power for a budget. Also some of the pro sound amps with large power. They may not be as clean but will play loud.
Outlaw or Emotiva may be something to look at too. They sell internet direct so the amps are pretty reasonable and folks seem to be happy with them. You might also look around for an old Kenwood M2a or some of the other vintage large powered amps.

You might also stumble into a Klipsch dealer to give them a listen. Polk are decent speakers but not really Rock&Roll style. Another good speaker which would offer more sensitivity and still sound good is Paradigm. Keep in mind though to replace the front three speakers will cost more than $500.00.

[blackraven]

Just go out and buy an Onkyo TX SR806 receiver with 130wpc. It will be more than enough for your speakers at loud levels. The Max power rating of your speakers has nothing to do with how powerful a receiver or amp you need.

You blew your tweeter's by playing them too loud and clipping the amp as stated earlier.

If you must get an amp, look into the 5ch emotiva amp. www.emotiva.com They have 7ch and 3ch as well. The 3ch may work well with your system. Hook the front and center to the emotiva and the rears and sub to your Onkyo. The 3channel is on sale for $499 and the 7ch is on sale for $549

[Luvin Da Blues]

You blew your tweeter's by playing them too loud and clipping the amp as stated earlier

My guess is he only wants it loud and not blow up anything. If he was concerned about SQ he would of heard the distortion and turned it down a tad. Just sayin'.

[Gerall]

I can recommed the Adcom GFA 5500. Will drive most anything you throw at it with ease. Dollar for dollar a great bang for the buck.

[Mr Peabody]

I should have mentioned I have a 5500 in another system driving some Dynaudio 60's. I think they are only 86dB efficient and this amp drives them to "very loud".and if your speakers can handle it the 5500 does big bass. The 555, is an earlier model and closer to the Pass original design if not, the original, I'd have to do some checking on the geneology.

Gerall, I'm just using a gtp-450 preamp. How's the Aric Audio sound? Does it have remote, which would be a must for this system as it's hard to reach from the treadmill. :) I've thought about doing something different with the preamp but the 450 isn't bad and has the tuner built in. I was thinking about going up to the 750 but I auditioned once and didn't hear a lot of difference between the 450 and 750. After seeing and hearing reviews of the 750 I wondered about the audition if something was wrong. But you know how something is said, and Stereophile gives it a nod and all the sudden it's good whether it is or not. I don't see many of them listed in systems and usually one or more are on Audiogon. The only real criticism I have of the 450, and you really can't criticize it because it is great for the price it was new and a steal used, the highs I'd like to be smoother, or less harsh, and a bit more resolution would be nice. The 5500 has an interesting sound, sort of a dark feel, I wonder if tubes would take it too far in that direction.

[02audionoob]

In the used Adcom market, the one I think is a steal is the GFP-555...but of course no tuner. The GFP-565 is supposed to be better, but it's famous and brings a much higher price than the GFP-555.

Speaking of Adcom, and getting closer to the OP's topic...The GFA-545 is usually available cheap on the eBay or Audiogon and although it's still just 100 watts per channel, it might be a more authoritative 100 watts than the Onkyo.

[Kevio]

If you believe the specs, your speakers are good for 250W continuous each so yeah, you could make use of a larger amplifier. 500 W per channel would not be an unreasonable match. I'm not sure the specs are believable though - the speakers only have 6.5" drivers. Moving up in wattage may just make smoke.

You are considering doubling power to 200W. Blackraven has suggested 130W. Neither of these upgrades is going to give you an obviously louder system. You need 10x the power to make a system sound twice as loud.

To get to the point where you apparently need to be where your ears blow before the equipment, you're going to need to buy some amplifiers and probably some speakers too.

[sallysue]

If you believe the specs, your speakers are good for 250W continuous each so yeah, you could make use of a larger amplifier. 500 W per channel would not be an unreasonable match. I'm not sure the specs are believable though - the speakers only have 6.5" drivers. Moving up in wattage may just make smoke.

You are considering doubling power to 200W. Blackraven has suggested 130W. Neither of these upgrades is going to give you an obviously louder system. You need 10x the power to make a system sound twice as loud.

To get to the point where you apparently need to be where your ears blow before the equipment, you're going to need to buy some amplifiers and probably some speakers too.


It's of no consequence, but I've heard that it takes 10db for the human ear to percieve the sound to be twice as loud. Ham fisting 500W into 6.5" drivers would be fun for the first 30 seconds anyway :8: Forget about compression, it'll melt.

[Mr Peabody]

Decibels are a ratio: http://www.phys.unsw.edu.au/jw/dB.html

However much you perceive increasing amp power will help, just adding some punch and clarity can improve things. I personally don't think a 545 or 5400 at 100 or 125 watts will be worth the expense for the little gain he would receive.

If one had a 500 watt amp it would be better on the speakers than a 50 watt amp, it's clipping, or driving the amp past it's capability that blows speakers. As long as a speaker receives clean power it can usually handle a surprising amount of power. Because an amp is 500 watts doesn't mean the speaker would ever necessarily receive that much. It's not the size either, my 2.5's use 6 1/2" drivers and they've handled a 250x2 Krell power amp with no problem. The question would be can these Polks handle 250 watt RMS or peak. Either way the same principles I stated above apply.

It's more rare but you can over power a speaker by the cone being pushed out further than it was meant to go. Going past it's designed excursion. So using a true 500 watts on a 250 watt speaker could lead to problems if the amp was turned to full throddle.

[02audionoob]

I don't know much about the technical aspects of it, but I have an Adcom GFA-545II sitting around that I'm not using at the moment and I have a Denon AVR-85 receiver that I am using for its surround capability. When it comes down to which one can fill up a room with sound, no question the Adcom has a very noticeable advantage in my setup...probably as much as the difference between my GFA-555II and the GFA-545II.

On the topic of the speakers...maybe they ARE the issue. Sure the Polk speakers have a reasonable efficiency of 90 dB. But that's at 1 watt. What about how loud they play with 10 watts? or 100? Maybe they just can't play as loud as desired.

[blackraven]

Buy an amp like an NAD. They have great dynamic Headroom and a soft clipping feature. I have heard them at their limits and they can save your speakers.

You might want to consider these monoblocks- http://www.outlawaudio.com/products/2200.html

[E-Stat]

Neither of these upgrades is going to give you an obviously louder system.
I find that a 6 db increase in level is easily audible and pretty significant. To each his own.

rw

[blackraven]

I find that a 6 db increase in level is easily audible and pretty significant. To each his own.

rw

I totally agree.

And my earlier recommendation about jumping up to the Onkyo 806 at 130wpc was was mainly so he does not clip his amp. 30wpc is significant when you take into account the added dynamic headroom. I can easily tell the difference in volume between my 55wpc integrated and my old 100wpc receiver.

HMT, one other thing to try is to make sure you have a quality speaker cable, at least 16g or heavier. 18-24g will put more strain on your amp with added resistance. It may not be significant because your speakers are not that demanding. With speakers like my Magnepans, I have found heavier gauge wire make a big difference.

[sallysue]

It's more rare but you can over power a speaker by the cone being pushed out further than it was meant to go. Going past it's designed excursion. So using a true 500 watts on a 250 watt speaker could lead to problems if the amp was turned to full throddle

I was speaking of full throttle and kidding more or less - of course you don't have to turn up the amp full throttle.I understand decibels but thanks for the link.

I'm reminded of a question I asked Dr. Toole (in person) of Harmaon Kardon International.

How much amplified power do you recommend for the average system?

"All you need is about 50 quality watts, that's all"

Dr Toole is the chief scientist for HK (Revel, Infinity,Crown,JBL,Lexicon,HK and others) and his doctorate is in physics. Paul Barton (PSB) trained under Dr. Toole before starting his own company.His name is as famous in the speaker industry as M. Jordan is in the basketball business.

I'm not taking a side either way on amplified power - but there you have it.

[Kevio]

The rating I saw for the Polks is "250 W continuous power". Maybe I'm being misled but I take that to mean you can drive these at 250 W RMS indefinitely and they won't smoke.

The distinction between peak and continuous power is important because the difference between the two can be 10 dB or more in terms of level or about 10x in terms of power.

I agree with everyone else here that if you overdrive a lower powered amp, you can blow the tweeters even in robust speakers. I like Blackraven's idea of trying to get an amp that has good behavior (e.g. soft clipping) when overdriven.

[Kevio]

I find that a 6 db increase in level is easily audible and pretty significant. To each his own.I agree that 6 dB is quite significant. Most people perceive it as an approximate doubling of level. Unfortunately, doubling power (e.g. from 100 to 200 W) makes your system only 3 dB louder. That's the way the math works p = e^2/r. I hope you agree that while 3 dB is noticeably louder, it is not impressively louder.

[sallysue]

I agree with everyone else here that if you overdrive a lower powered amp, you can blow the tweeters even in robust speakers. I like Blackraven's idea of trying to get an amp that has good behavior (e.g. soft clipping) when overdriven.
NAD makes a "soft clip" amp I think.

Reserve head room is a game that's played on the reciever market for sure and the danger of roasting you're speakers is real if you turn it up too long on lesser models. The HTR series ( I think it's HTR ) from Yamaha and the RX-V line definately do not have the same power supplies in them and the specs are deceptive. For the HTR series they pick a narrow band of frequency(s) that's easy drive and rate the amp at - let's say at 100 watts a channel. That's not the same as 20-20 at 100 watts a channel.

[HMT]

Thanks Mr Peabody and all…..Wow…You guys are awesome…Thanks for all the comments suggestions….

Not sure if this would make any differences, but when I said I turn it loud when listening to music, I meant I used it for Karaoke. With Karaoke and turn it loud prob. what blew for tweeters. I wanted to mention this so that you can can see if 200wpc power amp would prevent my tweeters from blowing up again or not before I am buying it (I do turn it that same level when watching movies too…I know I am deaf...) or should I wait and save money on some of the high efficient speakers (like 98db or 100db from Klipsch) and keep my receiver. From what I've read I'd need (in my scenario) to have 1000w receiver to gain 10db (i.e. to double the loudness) so that I won't overdrive the amp. If by putting the 200wpc power amp, it really only gains me 3db (which in theory I would turn the volume to 67 instead of 70). Am I understanding this right? That's still high and still consider "overdrive" the receiver?

If the max volume is 90, what is considered the maximum SAFE volume level (where it's not clipping distortion)? 50, 60?

Mr. Peabody,

These Polk speakers are 250W continuous (RMS).

Blackraven,

I am using a 12gauge speaker cables (not brand name though...bought it from Home depot), but they're 12gauge.


This forum ROCKS!!!!!!!

[sallysue]

or should I wait and save money on some of the high efficient speakers (like 98db or 100db from Klipsch)

I'm a huge Klipsch fan for HT. I know just saying that will cause a firestorm but I am. Klipsch f'in rocks for HT. You will need to temper the horns - they can be bright. But for rock music and especially jazz, they also do well. I had a Klipsch Refrence HT system that I'd put against all but the most stupid expensive systems.( In fact I still have the speakers at my sisters and I don't use them becuase I don't have the room right now - city living - gotta love it).

Some things about Klipsch - brightness.

A lot of the recordings you hear have the higher frequencies boosted because at the time of release the high frequency response of speakers wasn't good = sound shreekingly bright.

Movies - I don't know if it still holds true anymore but for years the sound tracks being released (for some movies) are just as they are in the theater. This is important because in the theater, the speakers are behind the screen and the sound flows through pin holes. Low to mid range frequencies have no trouble punching through to the audience but high frequencies - they need to be boosted significantly. A lot of good prepros will have "theater soft" for this reason - it gently cuts off the boosted high frequencies from the sound track. If you don't have this feature, just turn down the treble.

If you have Klipsch speakers with boosted high frequencies - the speakers will reproduce them faithfully and painfully :smile5:

Rock on!!!

[E-Stat]

Unfortunately, doubling power (e.g. from 100 to 200 W)...
For some reason, I thought his current amp was 100 watts total or 50 watts /channel. Indeed that is only a 3 db change assuming everything else is equal.

Which is sometimes not the case with AV receivers given the plethora of power rating schemes. I inherited a Kenwood AR104 receiver which is rated @ 100 watts per channel (yes RMS 20-20k both channels driven). Having said that, it does not have the current capability of an older Threshold Stasis 3 power amp with the same power rating - which happens to weigh more double that of the Kenwood. I suspect it would not be as happy as the Threshold driving the challenging reactive load of my electrostats. :)

A 3db difference is still clearly audible (if not "impressively louder") even to untrained ears. I wish I had an additional 3 db headroom added to my VTL 450s.

rw

[E-Stat]

If by putting the 200wpc power amp, it really only gains me 3db (which in theory I would turn the volume to 67 instead of 70). Am I understanding this right? That's still high and still consider "overdrive" the receiver?...If the max volume is 90, what is considered the maximum SAFE volume level (where it's not clipping distortion)? 50, 60?
Technically, maximum output is always 0 db. The volume control is simply a dimmer and everything is a negative figure relative to maximum. Also, different sources have different output levels so a setting that will just clip the amp on one source may not even come close on another. My DVD player requires more gain, for example, than the cable box. I went to the Onkyo site and looked at the manual. Unfortunately, it provides no clue as to what those numbers mean. Also, the receiver is only rated 85 watts with all channels driven.

When amps clip, they start sounding edgy and rough. You will likely need to experiment as to when that occurs. Good luck!

rw

[Kevio]

Not sure if this would make any differences, but when I said I turn it loud when listening to music, I meant I used it for Karaoke.:idea: A quick way to blow tweeters is feedback through a microphone. Do you want to cop to that happening? Stereo systems are not well protected against the shriekback, transient and overdriven signals a PA system can experience.

[Mr Peabody]

If you've read the link you realize that decibals are a bit more complicated than 3x or 10x = whatever. I'm sure all of you have had experience enough with hi fi gear to know it's not that simple in real life. Here's a couple of examples, the 5500 is rated at 200 wpc where the 5400 is 125 wpc when putting the larger amp in place of the smaller with only 75 wpc difference there was still a significant change in the loudness that could be achieved. When I pulled my Krell, 250 wpc out of my system and went with a 50 watt Conrad Johnson tube amp driving the same speakers with same sources, and I'd like to point out that the MV60 provides 50 watts of "quality" power, there was a lack of power in my system. I could get a nice listening level with clean sound but not much beyond that. With my Krell I usually gave before it did. So I had the MV60's mono'd to 100 watts, this still don't approach the power and authority of my Krell but the extra 50 watts made a huge difference. All the 3x and 10x might look good on paper and it sure leads to debates but you need to think about your own experiences when sometimes a hand full of watts can make a big difference. When I gave my daughter our car years ago I had it decked out with Infinity Kappa components. Kids being kids, it wasn't loud enough, in other words her friends couldn't hear her for a block before she arrives, so after she blew my tweeters I pulled the Infinity out which were about 88 or 89dB efficient and had her buy some Boston Acoustic coaxial stuff about 92 or 93 dB and that small jump in efficiency made a huge difference in that car system with everything else exactly the same.

The thing is HTM you can have 10,000 watts and there's no guarantee you won't blow your tweeters again. Not blowing speakers comes with listening to your system and realizing when it has reached it's limits. When the music starts to no longer sound clear it's time to back off the volume. At loud levels what you are listening to should be as audible as when it is at a lower level. It's obvious that you need to live to learn with less or make a change in your system. A few members have gone the direction of adding amps to receivers and have posted favorably about it. I know that Onkyo receivers are true to spec and have more current than most mass receivers so if you aren't happy with their 85 watts, you need an upgrade some where.

[HMT]

[QUOTE=I know that Onkyo receivers are true to spec and have more current than most mass receivers so if you aren't happy with their 85 watts, you need an upgrade some where.[/QUOTE]

Maybe it doesn't make any difference, but just wanted to clarify that mine is 100wpc...spec is below..

Power Output* (8 ohm, 20 Hz-20 kHz, FTC) -
Front L/R 100 W/Ch
Center 100 W
Surround L/R 100 W/Ch
Surround Back 100 W
Power Output* (6 ohm, 1 kHz, FTC) -
Front L/R 125 W/Ch
Center 125 W
Surround L/R 125 W/Ch
Surround Back 125 W
Dynamic Power** (front) -
3 ohm 230 W/Ch
4 ohm 170 W/Ch
8 ohm 115 W/Ch

[Mr Peabody]

:) It just drives the point home more that you need mo juice or keep your eye out for a deal on more efficient speakers.

[sallysue]

Maybe it doesn't make any difference, but just wanted to clarify that mine is 100wpc...spec is below..

Power Output* (8 ohm, 20 Hz-20 kHz, FTC) -
Front L/R 100 W/Ch
Center 100 W
Surround L/R 100 W/Ch
Surround Back 100 W

I'm not familiar with Onkyo but a lot people like them. Sounds like you've got pleanty of power for effecient speakers such as Klipsch or JBL and some others. You might have some trouble running electrostats though, I wouldn't recommend it, most stats are 4 ohms or less and require a fearless amp with prodigous power.

Anyway, there is no need to consider less efficient speakers when there are pleanty of good offerings that are efficient. Speaker build/designing (just like aircraft and bridges) is a trade off of materials that will perform in certain ways under certain conditions. Polypropylene cones are great but they have trouble when they start heating up.Paper pulp cones work fine also but there can be a consistency problems with the raw wood pulp. Then there is the enclosure itself, ported boxes are generally more efficient that sealed ones and both have advantages in different areas. So to correct some of the short comings of the polypropylene and wood cones, engineers start experimenting with coatings help prevent distortion - the speaker cone gets heavier and less efficient.Sound hasn't changed since speakers were first made - MATERIALS HAVE. This is why you see a zillion different cone materials on the market, the big trade of perfectly stiff, will never break up under stress and is perfectly efficient - no such material exists or ever will.

[E-Stat]

Maybe it doesn't make any difference, but just wanted to clarify that mine is 100wpc...spec is below..
With two of the six channels running simultaneously. The specs are found in the manual here. (http://63.148.251.135/redirect_service.cfm?type=own_manuals&file=TX-SR701_601_E.pdf)

100 W per channel min. RMS at 8 Ω,
2 channels driven from 20 Hz to 20
kHz with no more than 0.08% total
harmonic distortion.

All channels: 85 W per channel min. RMS at 8 Ω,


rw

[sallysue]

E-STAT is right HTM

Below are the specs for the RF83 by Klipsch, just an example....

you could make an electric generator from a gerbil on a wheel and they'd play fine.....


frequency response 33Hz-23kHz +/-3dB
power handling 150W RMS / 600W Peak
sensitivity 98dB @ 2.83V / 1m nominal impedance 8 ohms compatible
high freq crossover 2000Hz
high frequency drivers 1" (2.54cm) Titanium diaphragm compression driver mated to 90x60 square Tractrix® Horn
low frequency drivers Dual 8" (20.3cm) Cerametallic™ cone woofers
enclosure type Bass-reflex via dual rear-firing ports
height 43.6" (110.7cm) (w/feet)
width 9.5" (24.1cm)
depth 16.25" (41.3cm)
weight 66lbs (30kg)
finishes Black Ash woodgrain vinyl
built from 2006

[HMT]

Thanks for all the device guys...I think I'll keep an eye Klipsch WF35...it's a little cheaper and they look sexy...Thanks again...

[Gerall]

I should have mentioned I have a 5500 in another system driving some Dynaudio 60's. I think they are only 86dB efficient and this amp drives them to "very loud".and if your speakers can handle it the 5500 does big bass. The 555, is an earlier model and closer to the Pass original design if not, the original, I'd have to do some checking on the geneology.

Gerall, I'm just using a gtp-450 preamp. How's the Aric Audio sound? Does it have remote, which would be a must for this system as it's hard to reach from the treadmill. :) I've thought about doing something different with the preamp but the 450 isn't bad and has the tuner built in. I was thinking about going up to the 750 but I auditioned once and didn't hear a lot of difference between the 450 and 750. After seeing and hearing reviews of the 750 I wondered about the audition if something was wrong. But you know how something is said, and Stereophile gives it a nod and all the sudden it's good whether it is or not. I don't see many of them listed in systems and usually one or more are on Audiogon. The only real criticism I have of the 450, and you really can't criticize it because it is great for the price it was new and a steal used, the highs I'd like to be smoother, or less harsh, and a bit more resolution would be nice. The 5500 has an interesting sound, sort of a dark feel, I wonder if tubes would take it too far in that direction.

When I first received the Aric preamp and burned in the 12at7 tubes I did notice a difference in clarity and soundstage. Less bass than with my Adcom pre, but overall better. I tried a pair of JJ 12ax7's but they had way too much gain. I got a set of NOS RCA 12au7 cleartops and the difference was quite significant. Way better soundstage with a nice well balanced sound. Setting up the matching pot to the input of the 5500 was a trial and error effort, but once I got it dialed in was a great improvement in overall audio quality. It is a barebones preamp with NO remote, agreed a liability as when you are into darkened room listening, it is annoying not to have volume control. I use the Cambridge remote for track switching but still have no volume control. I also liked the audio output contol the Adcom pre has as you can get a bit of shaping depending on the recording. I ended up using the Aric as an external processor that I can switch in or out on the Adcom preamp. All in all, givern the cost of tube preamplifiers, the Aric was a good dollar for dollar buy at 275us.
I am also sort of acoustically crippled as I am in a new home and have the band room in with the sound system (14x24room), tight burbur carpet and bare walls, so acoustics are less than desirable. I'm working on that one, and may end up moving the audio system to another room.

[HMT]

Guys..I have a dumb question that I'd like to understand for my own knowledge. What is the speaker wattage represents anyway...I meant would it make any difference if my speaker was 150w RMS instead of 250w? Assuming everything is the same right now and I turn volume level to 50. When I replaced the 250w speakers with 100w speakers, would the sound be less loud (also at level 50 same everything else)? Just trying to find out what is the advantage of having 250w speakers vs 150w (or less) speakers...Also if the sensitivity (efficiency) is too important and also help receiver working harder (for my case anyway), why wouldn't some speaker manufactures make it 100db like Klipsch and some others? Is it cost? Again I am just trying to understand...

Thanks

[blackraven]

The watts rating of a speaker has nothing to do with how loud it will play. Its the speakers sensitivity rating that counts. A speaker rated at 85dB will not play as loud as a speaker rated at 95dB with all things being equal.

The power rating is the minimum power needed to drive the speakers adequately and the higher number is given as to what the speaker can reasonably handle and not blow up. Thats as simple as I can explain it.

[Mr Peabody]

My thought on why manufacturers don't all make high efficient speakers is because most of them use a different design and material some where in the speaker's sum of components. And when trying to design a speaker, manufacturers may have a different goal for their speaker they are trying to achieve and this goal may involve compromises, one of which might be sensitivity. Don't think because Klipsch is a higher sensitivity speaker that they are some how superior. In my opinion they are average at best, and I'm being kind, at a near premium price. Some people like them, they even have their own forum, and in some instances, as yours, they may fit a purpose very well. Klipsch still uses paper cones which allow for the sensitivity but paper is prone to distortions. Hardly any quality manufacturer of speakers uses paper any more. This is one of those compromises I mentioned, use paper and have an high efficient speaker or use a different material that is stiffer and gives better sound but less efficient. Klipsch also uses horn tweeters, the only home manufacturer that I know of that does. Think about the difference between talking normal and then cupping your hands on either side of your mouth. It projects your voice a bit further in front of you but may limit it to the sides.

Blackraven answered the rest of your question about as well as it could be said. The power rating "watts" is just a guide given by the manufacturer to help match gear. The important thing no matter the rating is to keep the power to the speakers clean, no clipping signal. Don't get hung up on power ratings. They really don't mean a lot. Some companies tend to use the extreme highest rating they legally can to make their speaker look better, some post conservative ratings. For example, my 5500 is rated at 350 watts into 4 ohms and I am using a 4 ohm speaker rated at 150 watts continuous with no problems.

Here's a review I found on the Adcom gfa-5500. It also reminded me it has a very useful feature for you, LED's on the front that will light when the amp approaches clipping level, if you paid attention to that light, it could prevent further speakers from damage. http://www.hometheaterhifi.com/volume_3_3/v3n3k.html

I saw on Audiogon.com two gfa-555 (200x2), one was only $225.00. No 5500's but a few 5503 which would be 200x3 for $500.00 and up.

[HMT]

Well explained. Thanks both.