Damage speakers by gain?

[mnaines 10+ year member]

Honestly, I would run all the tests at normal listening levels. No point in turning the volume up to max just to run an oscope test.

 

[thejoker989 10+ year member]

Joker, you still do not understand...I am saying road noise and other external noises mute out the audible sounds. The road noise "cancels out" the 30kHz signal, is basically what I am trying to say. Road noise, wind noise, and engine/exhaust noise, when they enter the cabin of an automobile, act to "mute out" at least some of the audible noises inside the automobile. What I am trying to say is this: Unless you are extremely good at "tuning out" distractions, then external noises entering the cabin of the car will make it harder to hear the music that is playing inside the car.
Is this easier to understand?

I could be in a soundproof room and would still never hear 30 khz, so no i dont understand.

 

[DBfan187 5,000+ posts]

Have you tested the pre-outs with an oscope to make sure there is no clipping at volume 61/62? I would tend to suggest a lower number, to avoid pre out clipping and to be able to get full volume out of downloaded tracks that may have had a lower recording volume.

Yes. 61/62 is were to set the gains - with all processing turned off.

 

[thejoker989 10+ year member]

Yes. 61/62 is were to set the gains - with all processing turned off.

Yessir... good luck playing a track that has a low recording level at maximum system volume. I would use 55/62, that way if a track was recorded low I could turn it up and achieve my maximum system volume.

 

[DBfan187 5,000+ posts]

Yessir... good luck playing a track that has a low recording level at maximum system volume. I would use 55/62, that way if a track was recorded low I could turn it up and achieve my maximum system volume.

that's why you can set your gains using a 3:1 ratio.

 

[thejoker989 10+ year member]

that's why you can set your gains using a 3:1 ratio.

Please let me in on that and tell me what it means.

 

[DBfan187 5,000+ posts]

http://www.audiogroupforum.com/csforum/showthread.php?t=8910&highlight=ratio

 

[GrnEydDvl 10+ year member]

Honestly, I would run all the tests at normal listening levels. No point in turning the volume up to max just to run an oscope test.

He didn't say MAX. He gave a specific answer for a specific reason. You set your gains with your volume set to just under where your head unit begins to clip.

You can, of course, disconnect your speakers while setting your gain.

 

[thch 10+ year member]

Please let me in on that and tell me what it means.

in short, it is possible to set the amp up so that even with the HU turned up all the way (or 3/4ths of the way), you have no chance of clipping*.

but for many reasons, when this is done, the results may not be satisfactory. if the source was recorded at lower levels, the volume may be too low. also, most people will tolerate mild distortion if it allows them to play the music a little louder. also, clipping has certain compressive effects -- the light bass notes become louder and the heavy bass notes stay about the same -- the music is overall louder.

to do this, a lower level test tone is used when using the DMM method. thus the amp SHOULD put out 9x the power (for a 3:1) of the 1:1 setting. it can't. for a sine wave, this will be distorted. for normal music, the effects are less pronounced.

as for supertweeters.

CD music is sampled at 44khz. any real tones at 30khz would have been aliased to 8khz. any signals at 30khz have are either fabricated (eg, from distortion or from some DSP), are noise, or have come from a non-CD source (SACD or DVDa)

* not 100% true, but reasons are overly technical.

 

[squeak9798 5,000+ posts]

With midrange speakers i would just set the gains by ear. It is very easy to tell when midrange speakers begin to distort. At least much easier that woofers.
Pick a song that you know really well and turn the gain on your amp all the way down. Next set the h/u to the volume number that you would prefer to be your theoretical maximum. Usually about 3/4 to 7/8 of your h/u max. Then turn the gain up until your speakers start to distort. And thats it.

The reason I suggested the DMM method is due to his level of experience. For the novice, I feel it it much better to atleast give them a target starting point for gain level setting, since this takes much of the "guess work" out of it, which they may not really have the experience level to properly judge yet. Once they have the gain set using the DMM method, they can listen to it at that level and decide whether or not the gain setting needs minor tweaking from there.

 

[helotaxi 5,000+ posts]

OK. I know people are going to bash me for this, but if you reduce the frequency response range, it will mean less overall quality and the sound will not be as clear, and since you say that you prefer clear music over loud music, my best advice is to keep the frequency response at its full range.

You get all bent when squeak says not to listen to you because you don't know what you are talking about and yet you continue to prove his point with every successive post.

Also, at best, the human ear can hear sounds between 20Hz and 20kHz, so if you are going to adjust the frequency response, put the top end no higher than 20kHz and keep the low end at 30Hz.

This is bad advice for the OP. I'll even go so far as to explain why. He's running potentially max RMS to a set of midrange speakers (the tweets are irrelevant at this point). Power handling for speakers is based solely on thermal limits and doesn't take the mechanical limits of the driver into account. At really low volumes, you could easily run a full range signal to the speakers without risk of damage. You would get a full range output as well, however because the human ear is less sensitive to low freqs, you wouldn't hear the low frequencies produced by the mid. Now turn up the volume with the same signal. You would probably be able to quite easily blow the mids before you approach their rated power limit by feeding them a full range signal. The speaker will try to reproduce whatever signal you send it. Since a midrange has a very limited excursion capability, and lower freqs cause exponentially higher excursion it would be a very simple task to exceed the excursion capability of the mid. Even before you started to cause damage, the cone would likely start to break up and cause a lot of distortion. Since the OP wants clear sound, distortion is a no-no. Especially the easily preventable type. By adding a highpas filter in the 80hz range the likelyhood of cone breakup will be reduced (or at least the volume level required to get it will be much higher) and the mechanical power handling of the driver will be greatly increased so there is less worry about blowing speakers.
Quick lesson for this forum, there are a few of us on here that will shoot down bad advice in a big hurry. Some of us also have a tendency to make the purveyor of such bad advice look and feel like a complete idiot. The purpose of this is two-fold. 1) All who read the thread will quickly realize that the poster doesn't know what he is talking about and ignore his advice (the primary goal by the way) and 2) Hopefully the poster will get the hint that unless they are totally correct in their advice, they will be called on their BS by someone that does have the correct info and unless they want to continue to be made the fool, they will abstain from polluting the forum with their crap.