Benefits of a seperate amp?

[zumbo]

Sorry if you had mentioned that in earlier posts I must have forgotton. Now I can understand how that little Adcom got into trouble before the speakers. And you are right, the speakers may not yield a lot of SPL but depending on the design, it could suck a lot of juice.

I wouldn't expect you to remember. God knows I don't remember much.

But, a load is a load. Which is why I described the amps to be under the same load. One runs out of gas, and the other doesn't.

Believe me, seeing as how I paid three times more for the Adcom, I would certainly want it to perform better than the Denon. But, I didn't expect it to. It does what it was designed to do, and it does it well.

It's just a shame Denon don't make these fine amps anymore.

Again, my replies were just to inform the OP of what clipping actually was. I got the idea he believed clipping was protection mode, or simply shutting down.

 

[dem beats]

dem, i really don't think my headroom is lacking anything on this receiver, no matter what i throw at it ive NEVER been able to drive it into clipping, the other day i got 115dB at 35hz out of both channels without clipping, ive never had or played with any receiver that can do that with the same power rating as this receiver.

How did you measure the clipping?

Also 115 at 35hz is awesome, but was that on a test tone or dynamic audio?

As I said I'm not trying to critisize you, or what you want. You probably have no need for an amp. It may just not be a worth while investment for your needs currently. i.e. Perhaps more dynamic power and a flatter speaker response would be less flat in your room.

How big is the room you're in? In a smaller room with closed doors you can really get awesome room gain. It's a bit like a subwoofer in car audio SPL with cabin gain.

In an an huge room or a deadened chamber the SPL at any given hz might be different. Also there may be some corner loading bass boost, who knows. Untill you can measure everything precisely it's an unknown. I have access to hundreds of thousands of dollars in measuring equipment and HUGE dead rooms via a friend at his job. For funsies we measured a cheep but powerfull pair of floor standers that would vibrate his tiny living room with bass. In the chamber with max bass boost, the roll off was >5 db at 40hz.

Again to your original question, yes amplifiers will allow you to have more flexability and "future proofing" and may be a money saver in the long run. Do you need one for your rig, well you answered that alread as by your measurements and ears you don't notice any issues.

 

[Hocky]

You do know that clipping is not something you hear, right?

Unless you have an amp with clip indicators, you probably don't know clipping is occurring.

If you can't hear clipping, you're either not familiar with what you're listening to or are not actually listening. Maybe you don't hear it when it only clips for 1/4 of a second on a big transient, but if you've pushed the amp into clipping every dynamic you most certainly can hear the distortion.

 

[yepimonfire]

You do know that clipping is not something you hear, right?

Unless you have an amp with clip indicators, you probably don't know clipping is occurring.

Two things to note.

1) My Adcom has clip indicators. When it is allowed to clip continuously, I can get a slap from the speaker on the channel clipping. Very seldom that the speaker will slap, but the amp clips a good bit during high-output such as a concert dvd.

2) In a separate system, my Denon amp delivers double the power my speakers call for. I have gotten a slap on this system, but the amp was not clipping. The speakers were being over-driven.

you can hear clipping, clipping generates serious harmonic distortion. i've heard it several times. every amp i have sent into clipping on low frequencies it starts generating a higher frequency noise that sounds awful. and dem, i was in a fairly large living room without doors and the 35hz was a 35hz pure sine wave. clipping on SS amps generates square waveforms, square waveforms are very easy to distinguish against a sine wave.

 

[GranteedEV]

you can hear clipping, clipping generates serious harmonic distortion. i've heard it several times.

Hard clipping, yes. Soft clipping on the other hand is a different deal.

 

[yepimonfire]

don't all transistor amps hard clip? all i can say is i never heard any distortion in the sound.

 

[GranteedEV]

don't all transistor amps hard clip? all i can say is i never heard any distortion in the sound.

yea, but i can imagine limiting circuitry being in place before the amp stage, simply to prevent a signal strong enougjhto drive it to clipping from reaching with its full amplitude.

If anything it would be a smart move. either way if you're happy with what you hear then that is the important part as it means your amp is perfect for your needs.

 

[dem beats]

Greanteed was concise and accurate there where I could not be.

If you are happy with what you hear, then the amp isn't needed. It does however have some huge benefits.

 

[j_garcia]

don't all transistor amps hard clip? all i can say is i never heard any distortion in the sound.

I said this before, just because you don't hear it doesn't mean it isn't occurring.

yea, but i can imagine limiting circuitry being in place before the amp stage, simply to prevent a signal strong enougjhto drive it to clipping from reaching with its full amplitude.

If anything it would be a smart move. either way if you're happy with what you hear then that is the important part as it means your amp is perfect for your needs.

Exactly. Your system can clip long before you hear it. When you DO hear it, it is already well beyond the point of OK.

 

[GranteedEV]

wait, I was refering to soft clipping. but yes, we can't quite hear 1% THD but a measurement would show it as a clipped signal.

otoh 5-10% THD is like nails on a chalkboard.

 

[j_garcia]

wait, I was refering to soft clipping. but yes, we can't quite hear 1% THD but a measurement would show it as a clipped signal.

otoh 5-10% THD is like nails on a chalkboard.

Yeah, I'm not saying that it is dangerous or anything, only that the typical system, when pushed, will have some clipping before it is obvious that it is going on. So to say that there is no distortion because one doesn't hear it isn't the whole story.

 

[Pyrrho]

Greanteed was concise and accurate there where I could not be.

If you are happy with what you hear, then the amp isn't needed. It does however have some huge benefits.

It can have huge benefits, but it can also be completely pointless and irrelevant. If the amplifier in a receiver is adequate to drive the particular speakers in question, then there is no benefit whatsoever to buying a power amplifier. It is only when the amplifier in the receiver is not adequate that a power amplifier is of use.

In my case, I have several systems set up in my home. With my home theater, my receiver's amplification is more than adequate to drive the speakers attached to it to sound levels beyond what I ever want to hear. On the other hand, I have a pair of 3 ohm Apogee speakers in another system, and for that system, I use a separate power amp that is rated for use at that impedance (and below). If I had a bunch of those Apogee speakers for my home theater, I would not even try to drive them with the receiver I have, but would buy several power amplifiers. But as things are with the speakers I am using in that system, it would be a total waste of money.

 

[dem beats]

I do understand that if you don't need more Db it could be seen as a waste, however, over time if you keep the amp and only replace speakers and processors you will probably save some decent money. It also allows you to be more flexable.

As I said, if you don't need it you don't need it. You may however someday want to upgrade to a set of them those hard to drive speakers, and then the investment pays off massively.

 

[Pyrrho]

I do understand that if you don't need more Db it could be seen as a waste, however, over time if you keep the amp and only replace speakers and processors you will probably save some decent money. It also allows you to be more flexable.

As I said, if you don't need it you don't need it. You may however someday want to upgrade to a set of them those hard to drive speakers, and then the investment pays off massively.

If someday comes when one does need to buy the amplifier(s), then one should buy the amplification someday, not now.

Also, people who are always replacing their speakers are generally wasting a lot of money. If you buy really good ones, they don't need replacing, and consequently there will be no greater need in the future for a special amplifier that one does not need now.

I do agree, if one needs an amplifier now, if one buys a good one, it is generally a good idea to simply keep it when changing processors or speakers. In the case of replacing speakers, at least until one is certain that one is happy with the speakers and will not be replacing them in the future with something that will again require it.

By the way, my approach on home theater receivers is to buy them for their features, and not spend extra for more power. If whatever has the features that one wants does not have an adequate amplifier section, then I recommend adding a separate power amplifier, instead of buying a more expensive receiver (unless we are talking bottom of the line versus one up from the bottom).

 

[dem beats]

We just disagree on timing. And the flat out fact is, almost NO one sticks with one set of speakers from now untill they push up daisies.

If I would have purchased seperate amps from the day one, when I upgraded I could have purchased processing stand alone rather than a whole received and saved a bundle. If I upgrade every 5 years to stay in line with current gizmos etc and only save 200 bucks in 10 years I could have saved 400 bucks, and that can buy quite a bit of amplification. And to me, it also allows for any other situations that may come up. It just plain IS more versitile.

The thread asked what are the benefits. It's been adressed that there are many. The only issue is diminishing returns and if the juice is worth the squeeze. I don't want to suss out grounding issues, my receiver makes that a moot point for the most part. More cables, more level matching etc etc etc. However, there is still very real benefits, acoustically or otherwise.


I don't use seperate amplification, because for me, it's not worth the hassle to make the change now. However when everything gets rack mounted and I run in dedicated power lines, well it will be quite a bit different.

 

[yepimonfire]

i have been guilty of changing my speakers alot when i first got into audio, mostly because i didn't know what i was doing and kept buying crappy speakers, so i finally bought some real speakers, bought some larger better speakers for the front and center and i doubt i will be replacing them anytime soon, or later.

 

[zumbo]

I actually run my Adcom 7605 up to clipping during concert dvd's. Right and left mains indicate clipping. That is where I keep it during the concert. It's clipping, but hanging in there. I will replace it in the future, but it is doing what is asked of it for now.

I do not hear it, nor do I have any indication it is happening. Just the clip indicators. I actually like the way it sounds at that point. I just don't like the fact the amp is not enough. The clip indicators are letting me know I have reached 1% distortion.

Tube amps are usually 1%, or above at rated power. While the clipping of tubes is described to be different, this seems to be what tube fans like.

Personally, I just want an amp that has the capability to go beyond what I need it to do. That way, clipping is never a concern.