Axiom Home Page Forums General Discussion Stereo State of Paranoia

I purchased my first pair of Axiom speakers (M60's) just this past Christmas. I have been loving life ever since. This was my first step into "hi fi" and it was a pleasant one. Anyway, since my purchase I have been extremely paranoid about damaging my M60's. I listen to various types of music at what are probably very high decibals. Some of the music I listen to has some pretty hefty bass to it. I own a Sony DE-545 100Watt reciever (the reciever and a sub will be my next two upgrades). Unfortunately this particular reciever does not tell me what decibals I am listening at...it only has an integer scale of 1 - 30.
I many times listen in the 22 - 27 range. I know the M60's are rated at 250 watts but is there anything else I should watch out for (besides clipping) that could potential damage my speakers?

If you ever rattling or distortion coming from your speakers, I'd be worried. Other than that, I'd just be worried about your ears.

Receivers can't tell at what dB level they are playing (without calibrating the dB level to match your speakers) because the loundess is dependent upon the sensitivity of the speaker. If you want to really know, you should get an SPL meter from Radio Shack.

I would also add, set yourself an upper limit on the volume knob and NEVER go past it. You mention the scale goes from 0-30. I would select say 25 and never push the volume past that point.
As you push a receiver/amp near that 90% and beyond mark, you are approaching its near max capability. Do not risk distortion due to the limits of the amp.
The volume it plays at 25 on your receiver is irrelevant. If you want more volume, get a more powerful amp/receiver. Even then, if the amp will outpower the speaker, you will get some maximum excursion noises instead if you crank up the volume too far (e.g. the speaker driver hitting the point at which it physically travels no further).
Again, this point would be damaging as well, but more physically as opposed to electrically.

If after all that you still want more volume, break out the piggy bank and buy a bigger set of speakers (or add more to the system).

the other thing to ask is if the extra 5 (say from 20 to 25) really gives you any additional volume? Conspiracy theorists (and I'm not sure I completely disagree) believe that manufacturers purposely tweak their machines so the most volume gain occurs in the first 1/2 of the volume range of the machine. So then, for example, someone walks into an audio store and is looking at receivers. They crank the volume up to halfway and it's extremely loud. They immediately think that going the other half would make it twice as loud, when in actuality, there's very little gain there. They're impressed with all the power, and buy the receiver. It's possible that 80% of your volume gain occurs in the first 50% of your recievers volume setting.

If you have a SPL meter (RatShack sells a nice one) you can measure the upper level that you like listen at. Do this by playing some music at what you think is the highest level that you like to listen at. Then without touching the volume dial, put on a test disc with some pink noise or a 1khz tone to determine the db level. You would then make note of where your volume dial is on the reciever.

I would definitly buy into the idea that manufacturer's rig their recievers so that most of the volume gain is in the first 50% of the volume control. However, I can definite noticable difference between then say 22 and 25 on my reciever. Is it a big a difference as 12 and 15...probably not. I guess my biggest concern was whether or not I could accidently damage my speakers with my current 100W reciever besides clipping.
I guess what really brought this on was a DVD I was listening to a few nights ago. I was listening to Rodger Waters Live in the Flesh and on a certain part of "Another Brick in the Wall(II)" I could hear a couple crackles coming from my left speaker. It only occured in one part of the song and when I went back and replayed it, it crackled in the same spot. More then likely it's the DVD. I then popped in a CD that has considerably more bass and listened at a comparable volume and it was smooth as silk.
Anyway, this just started making me paranoid that I might be damaging my speakers but more then likely is a crackle on the DVD and I have nothing to worry about.

The M60 is rated at 93dB with 1 watt, so 20 watts would give you 106 dB, with plenty of dynamic headroon and negligible distortion. No problem at all for your speakers. However, if you frequently listen at those levels for sustained periods, which I doubt you are, you will suffer hearing damage.

if your really worried about damaging your speakers,and you like to crank it up then consider seperates as a future upgrade and use a amp that has peak power lights on it so you know when your reserve power is exaustd then you can cut back the volume a little to a point when the lights no longer blink to avoid damaging your speakers ...ron

How much $$ would I have to drop for a decent pair of seperates? I assume a seperates are one amp per speaker?

Are you looking for separates for 2 channel or 5 channel?

The best part about separates is that amps tend to live nearly forever, so buying used is generally very safe, and can save you some serious coin.

You can find really good used 2 channel amps for under $400. Then you'd need a good preamp or processor. Rotel is a good brand to look into if you're looking for some bang for the buck deals in the separate market.

Audiogon is a used buyers paradise.

No, separates are a preamplifier (does component switching, DSP, volum control) and an amplifier (amplified the preamp output). You can certainly get 1 amp/speaker, but that's really expensive, generally.

Or you could just get a sub and offload some of that bass to it, thereby decreasin the load on your receiver.

This is another good source for used equipment.

check out the marantz mm 9000 on clearance-699.00 its a real good deal shipping included-then choose a pre amp that will fit your needs--...ron http://www.accessories4less.com

i have that DVD. i will go play it and see if i hear this crackling you speak of.

well i did hear a couple of clicks but that was all i heard. i didnt have it blasting though. if your usinng a PS2 as a dvdp that would probbly be the cause. ive had problems when i used mine as a dvdp in the past on that disc.

I was using a Sony DVD player...I have an XBOX not a PS2 anyway. I also only heard a few crackles and they were near the beginning of the song just after the camera pans away from behind the drummer. Like I said before, I'm 99.9% sure it's just the DVD. I popped in a few CD's aftewards and didn't hear a thing. I have some friends coming over this weekend to demo the speakers and I just want to make sure they sound tip top.
Also, thanks to all those who posted information on seperates and subs. I'd really like to get my hands on a HSU.

I had my reciever cranked up and the speakers never sounded distorted. My real real question was "Can a 100Watt reciever damage speakers that are rated at 250Watts if the reciever is cranked to its highest potential...excluding clipping?" I was wondering if their were any other variables other then wattage that could damamge my speakers. In my mind, as long as my reciever doesn't clip, I could crank up my 100 Watt reciever as loud as I want and never even get close to the speakers (250 Watts) maximum threshhold.

OK, time to show my ignorance..........What does clipping sound like?

rdwarn,
I would never recommend you crank up a 100w receiver thinking that your "250W" rated speakers will be fine.
They will not.

Forget the speaker ratings. They are virtually useless.
Buy as much power as you can safely afford.

See one of my recent posts (at the very bottom of the review) about the 'test' we did with Axioms and Tannoys on clipping and distortion with a Denon 3802 receiver.

Hi rdwarn,

Ignore the 250-watt power rating of the M60ti's. Buy as much power as you can afford. You can never have too much power--only too little. It's very easy to push a lower-powered receiver into clipping or incipient clipping (where distortion is rapidly rising), which sends a DC signal to the mids and tweeters and burns out the voice coils.

The advice about buying used separates is excellent. I have an old Yamaha power amp, 200 watts per channel into 8 ohms, which is more than 15 years old and is working perfectly. I've used it to drive all kinds of small, medium and large speakers.

As for distortion to listen for, if you hear a sharp "snap" from any of the M60 woofers (very unlikely), that means the voice coil is hitting the magnet structure of the driver and you should race to turn down the volume. In most cases, you hear increasing edginess or harshness as the amp's distortion is rising (odd-order distortion). With a genuine high-power separate amp, your ears will give out before the M60s do.

Regards,

Thank you for your insight. I frequent these message boards and have always found sound advice. I have pushed my reciever (Sony DE-545 100W) on several occasions to it's maximum with my M60's. I didn't hear any type of distortion, however, I will cease pushing my reciever to the max in the future. I DO NOT want to damage my M60's as you can imagine. Hopefully, I have not already damaged my speakers in my ignorance. They still sound as great as they did before.
One more question and then I will keep my big yap shut for a while...Does clipping over time destroy a speaker or can only a few mintutes of clipping destroy a speaker?

If clipping is severe, a few seconds are enough to fry the voice coils. If it's brief, a fraction of a second, and not severe, I doubt there would be any damage.

Regards,

Is it pretty obvious when the voice coils have been fried? I mean do the speakers sound horrible...do they work at all?

Usually they don't work at all, though sometimes the overheated voice coil will warp the voice-coil former (if the wires in the voice coil haven't shorted out) and you'll hear a scraping or buzzing sound as the former rubs against the magnet pole piece.

Likewise, sometimes speakers that are overdriven by boosted bass (assuming you aren't running a subwoofer), the woofer voice coil will hit the magnet structure with a sharp "snap" sound. Depending on the driver, this may also warp the voice coil so that it then scrapes on any heavy excursion bass note.

I recall this happening during tests of a quite interesting omnidirectional speaker from dbx, called the Soundfield, which bottomed its woofers when we played Dire Strait's Ride Across the River at higher listening levels. Several woofers had to be replaced to continue our tests for the magazine at the time.

Regards,

Interesting-- so this would lead to the conclusion that speaker damage is

1. Pretty much all-or-nothing, and
2. Sometimes the damage only shows up when the speaker is driven hard?

Or, put in the negative,
1. Very rarely does subtle-yet-meaningful damage occur, and
2. speaker damage very rarely affects moderate listening levels?

A friend just walked in and before he saw what I was doing, he said "You're out of your element! You have no frame of reference!" Is he right, or is what I said feasible?

Mike

I dunno about what you said, but your roommate seems pretty cool.