My amp vs receiver

[PENG]

3805 vs GFA555

I did a little experiment on my HT system today using a Hioki clamp-on meter and a RS SPL meter. The Hioki measures r.m.s. currents accurate up to 2 decimal points. Results obtained are as follow:

Measured at approx 2 meter from the speakers,
Using track one of Telarc's Copland Appalachian Spring at around 2m30s to 2m:50s.

3805 direct
At -10 dB volume:
SPL=92 dB, current=1.20A r.m.s.
At -3dB volume:
SPL=96.5 dB, current=2.82A r.m.s.

3805+GFA555
At -10 db volume:
SPL=92 dB, current=1.16A r.m.s.
At -3 db volume
SPL=95.5 dB, current=2.86A r.m.s.

The Denon actually achieved 3.02A at 91 db at one moment, and 3.13A at another. The 200 WPC Adcom never showed anything above 3A. I only have one ammeter so I measured each of the front channels separately but the currents appeared to be roughly the same. I did try the Adcom at 0 db volume just to see if it would push more than 3A and it did. I was tempted to do the same with my other 300 WPC amp but I am too lazy to move that 52 lbs mass around. (actually I could do it right where it is by playing the same CD on that separate system)

I don't know if the above results mean much but it does show the Denon could pump out at least 6A r.m.s. so its instantaneous capability is probably going to be much higher. I guess it also proves that even a lowly 3805 receiver can do a decent job when used to listen to 2 channel music with my 87dB sensitivity floor standing speakers.

I need to clarify one point, the meter I used is likely designed and calibrated to read signals with frequencies around 60 Hz (actually I checked their website today, my meter is designed for 40 Hz to 1000 Hz and can display true RMS values). I assume it would understate the actual RMS values when used to measure music signals that contain a full bandwidth of 20 to 20,000 Hz (this is probably still true).

Since the part of music I used contained mainly timpani, bass drums and gongs, the measured values were probably not understated by much.

 

[MACCA350]

Interesting, can you measure the voltage to the speakers at those levels?

cheers

 

[PENG]

Yes, I could, but I didn't. At that level the voltage won't be very high, probably around 12 to 15V peak when the bass drum hits hard.

 

[MACCA350]

That would mean its taking about 36-45Watts/channel to run those speakers at those levels(W=VxA). So going on its rated 120W, its using about 1/3 of its capability in that situation. Is that right, or did I miss something?

cheers

 

[PENG]

That's at 2 meters, the SPL would be lower at my normal listening position, but would still be too loud for me. I had my ear plugs on when I was taking those measurements. I would say the average power during the test was much lower than 36WPC, more like 8WPC but I am guessing. The Hioki was set to measure rms but that's rms within a very short duration(a few seconds at the most when those big drum hits). To get any meaningful average watts, I would have to play some rock or jazz music, not classical. My Hioki can be set to measure average, peaks and record max/min. I'll try that next weekend.

 

[MACCA350]

Sounds like fun, I think I'll try and get the AC Current Clamp Accessory for my Fluke Digital Multimeter and have a play also Let us know how you go.

cheers

 

[rolyasm]

I am a noob reading this, so trying to interperet data is difficult. Are you saying that your 3805 performed as well as an amp with a lot more watts per channel? If so, is it worth going to seperates if they really don't do that much? I am just building a HT and trying to figure this all out. I even thought about the Adcom 300w/ch or the Avalanche 300/ch with a pre/pro. Maybe I don't need this much huh? Thanks for the help.
Roly

 

[mulester7]

I even thought about the Adcom 300w/ch or the Avalanche 300/ch with a pre/pro.Roly

.....Rolyasm, if it doesn't negate new bicycles for the kids, or take food from the table, you won't regret this move....especially, when such an amp is paired with more power-hungry speakers, which imo, stand the best chance for the better sound qualities....but we've had reports it's with any speakers, haven't we?.....

 

[dponeill]

I am a noob reading this, so trying to interperet data is difficult. Are you saying that your 3805 performed as well as an amp with a lot more watts per channel? If so, is it worth going to seperates if they really don't do that much? I am just building a HT and trying to figure this all out. I even thought about the Adcom 300w/ch or the Avalanche 300/ch with a pre/pro. Maybe I don't need this much huh? Thanks for the help.
Roly

An amp is not going to sound better just because it has a higher power output. There are some here who would misslead you on this. As long as you have enough power to handle the sensitivity of your speakers, the size of your listening room, and how loud you like to listen, anything extra will cause no harm but will also not improve the sound.

 

[mulester7]

An amp is not going to sound better just because it has a higher power output. There are some here who would misslead you on this. As long as you have enough power to handle the sensitivity of your speakers, the size of your listening room, and how loud you like to listen, anything extra will cause no harm but will also not improve the sound.

.....(respectful pie-in-the-face).....

 

[PENG]

I am a noob reading this, so trying to interperet data is difficult. Are you saying that your 3805 performed as well as an amp with a lot more watts per channel? If so, is it worth going to seperates if they really don't do that much? I am just building a HT and trying to figure this all out. I even thought about the Adcom 300w/ch or the Avalanche 300/ch with a pre/pro. Maybe I don't need this much huh? Thanks for the help.
Roly

No, let me be clear, I am not saying the 3805 performed as well as an amp. This little experiment simply tell me when listening to 2 channel music (in my case mainly classical and jazz), and in my 11.5X18X8 room, I no longer have to wonder if the 3805 is current limited. It clearly isn't as under the conditions I described it put out as much current as the GFA555 did. The 555 is rated 200WPCX2 into 8 ohms or 325WPC into 4 ohms. It claimed to be 2, or even 1 ohm capable, so I trust it could put out as much currents as the source material call for under my test conditions.

Now if you want to use the 3805 or a comparable receiver for 7ch stereo listening, then I would think you need an amp under most conditions. Regardless, I am leaving the Adcom in the loop just for peace of mind. I have another amp for my dedicated 2 ch system anyway.

 

[mulester7]

I am leaving the Adcom in the loop just for peace of mind. I have another amp for my dedicated 2 ch system anyway.

.....amps everywhere....peace of mind, mine hind-parts, Sir Peng......

 

[PENG]

.....amps everywhere....peace of mind, mine hind-parts, Sir Peng......

Did I ever say I didn't like amps????????

 

[Reorx]

Nope. You never said that Peng.
I think mule was just throwing that out there for dponeill's sake.

Were you able to hear a difference in the quality of sound between amp and no amp?

What are you speakers specs? Sensitivity, recommended RMS, etc?

Reorx

 

[PENG]

Nope. You never said that Peng.
I think mule was just throwing that out there for dponeill's sake.

Were you able to hear a difference in the quality of sound between amp and no amp?

What are you speakers specs? Sensitivity, recommended RMS, etc?




Reorx

Yes, but I am not one who has a gifted hearing sense. I do not hear that "huge" difference. However, I can hear significant difference between different speakers. Significant enough that I am sure I can pass a DBT in most cases.

Speaker spec: 35-20,000 +/-3db, 87db, "up to 200W" 8 ohms nominal, 4 ohms minimum

 

[dponeill]

Nope. You never said that Peng.
I think mule was just throwing that out there for dponeill's sake.

Were you able to hear a difference in the quality of sound between amp and no amp?

What are you speakers specs? Sensitivity, recommended RMS, etc?

Reorx

I never said I didn't like amps either. I just have a problem with Mule's advice to everone that a more powerfull amp will aways improve your sound. I'm sure that most of these people looking for an improvement would do much better with a better sub or speakers.

 

[PENG]

I never said I didn't like amps either. I just have a problem with Mule's advice to everone that a more powerfull amp will aways improve your sound. I'm sure that most of these people looking for an improvement would do much better with a better sub or speakers.

I know what you mean. Amps are more fun because you can play with them, but to me speakers sound so different even when you look within the same manufacturer. Take Polk Audio for example, it is not difficult to hear the difference voice between the RTi10 and the LSi15.

 

[mulester7]

I just have a problem with Mule's advice to everone that a more powerfull amp will aways improve your sound. I'm sure that most of these people looking for an improvement would do much better with a better sub or speakers.

.....ok, an upgrade from a $49.95 sub to an SVS would probably be a more marked improvement on a system's overall sound quality....but....a substantial increase in watts-continuous WILL improve the sound quality of ANY speaker element including subs, DPoneill....I've experienced it 7-8 times.....also, others have chimed in, with reports you could tell they were smiling as they typed.....clean quality subs are important also, sure, but watts on the front three channels is something we just need to take for granted at some point, and just try....EVERYONE will hear a difference, but some persons are musicians more than others, and will give the most glowing reports that illustrate their Phoenix has risen from the ashes.....yes, I'm as tired of defending this topic, as you guys are of hearing the defenses....let's just let it lay, and let reports come in.....

 

[PENG]

It seems that we are becoming more agreeable, to me there are at least three main reasons why both sides are getting tired of debating the "amp/watts makes a difference".

1) People have hard time accepting the fact, or claims that some can hear more difference than others, reports range from "none/subtle" to "huge".

2) The "facts" from DBT reports, but DBT were done under some prescribed conditions to equalize many variables.

3) Many feel you can more improvements by spending the money on speakers than on amps.

The problem I see with 3) is that it holds true for me up to say speakers within the $3,000 a pair range. Beyond that, it will be hard for someone with say a pair of Paradigm S4, to upgrade to a pair of B&W 803D. You can get a lot of watts if you spend the same money on a high end amp and still use the existing one for your other channels, or system(s). Like mule said, amps everywhere......it's fun.....

That said, I am saving up for the B&W D series, diamond for men.............must be good.

 

[dponeill]

.....ok, an upgrade from a $49.95 sub to an SVS would probably be a more marked improvement on a system's overall sound quality....but....a substantial increase in watts-continuous WILL improve the sound quality of ANY speaker element including subs, DPoneill....I've experienced it 7-8 times.....also, others have chimed in, with reports you could tell they were smiling as they typed.....clean quality subs are important also, sure, but watts on the front three channels is something we just need to take for granted at some point, and just try....EVERYONE will hear a difference, but some persons are musicians more than others, and will give the most glowing reports that illustrate their Phoenix has risen from the ashes.....yes, I'm as tired of defending this topic, as you guys are of hearing the defenses....let's just let it lay, and let reports come in.....

And just as the Phoenix is an imaginary creature, if you want to hear a difference badly enough you will.