Me too if the meter was set to dBC slow, the Bob Katz article on monitoring level I linked earlier suggests 83dB for high dynamic range material and 77dB for current pop levels.
Just made an informal test and got 92.6 dB(Z) average and 96.5 peak at the listening seat. I will do another one during my lunch break. I will have to change the gain structure a bit in order drive the amps to higher levels. With the current levels I reach an excursion of +- 3mm approx. Will try to get to x-max. I am sure that it won't sound very clean anymore.
I also tried the listening level that I would call loud buit still comfortable and that was around 90 dB peak and 86 dB average. But this is a level that I can only use when I am home alone and definitely not for long.
Regards
Charles
I also tried the listening level that I would call loud buit still comfortable and that was around 90 dB peak and 86 dB average. But this is a level that I can only use when I am home alone and definitely not for long.
Regards
Charles
Overpowering? It just really starts to pump the room at that volume, I find it a bit too much. Maybe I'm delicate? 
I'm running faital 15" in about 100l (maybe a bit bigger) sealed enclosure with mindsp. Amp is just a pioneer receiver, maybe 80watts?
I've never come remotely close to using maxing it out but I've run a few 20hz test tones just to rattle my windows.
edit: it's the FAITAL 15PR400
I'm running faital 15" in about 100l (maybe a bit bigger) sealed enclosure with mindsp. Amp is just a pioneer receiver, maybe 80watts?
I've never come remotely close to using maxing it out but I've run a few 20hz test tones just to rattle my windows.
edit: it's the FAITAL 15PR400
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I just repeated the test with changed level settings of the power amps such that I can drive them higher. I turned up until the woofer amp (2x 700 Watts) ran in to occasional clipping and then backed off a little again until the clipping disappeared. I was wearing hearig protection in order to being able to hear details. It was not only "massage-level" but also "blow-dry" level. It was a loudness that is maybe cool to impress once in a while but definitely not for serious studio work. The SPL meter was an Android App called Decibel X, weighting was linear.
With the Rhianna track I thought I heard slight gargling at times at a level of 98 dB peak and 93 average.
With the Drake tune - which has slightly less dynamics due to that droning bass note combined with a less dynamic bass drum - I could go louder without clipping (I guess my next woofer amp is in the 2 kW category ). Paperwork was blown from my desk ! Peak was 103.6 dB and Average was 98 dB. Sometimes a hint of slight gargling (but not sure) when wearing hearing protection.
With the Kari Bremnes track I got 104.7 dB peak and 98 dB average with sometimes a little gargling.
Regards
Charles
With the Rhianna track I thought I heard slight gargling at times at a level of 98 dB peak and 93 average.
With the Drake tune - which has slightly less dynamics due to that droning bass note combined with a less dynamic bass drum - I could go louder without clipping (I guess my next woofer amp is in the 2 kW category
). Paperwork was blown from my desk ! Peak was 103.6 dB and Average was 98 dB. Sometimes a hint of slight gargling (but not sure) when wearing hearing protection.With the Kari Bremnes track I got 104.7 dB peak and 98 dB average with sometimes a little gargling.
Regards
Charles
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The only other lingering topic I can think of at the moment...are the comments regarding my subs not being like those of home theater....I didn't agree nor did it make any sense to me....ok I can easily see that, yes, I have a high efficiency woofers... Which is somewhat unlike a what? I always went to the Dayton 18" ultimax for a reference... The Acoustic elegance 18h+ beats or matches the sensitivity of the ultimax in every area. The Ultimax is a reference home theater sub is it not?
100db at 20db....is just that...how can it sound different because its coming from another woofer if both woofers are within xmax/power/etc...Both are in similar volume boxes...you know how this goes for comparing different woofers....we try to removal as many variables as we can....
I remember comments pointing to fs...ok lets have it...the Ultimax has a fs of 19hz and the 18h+ has a free air resonance of 30hz... So what? In a vented alignment fc owns all (John of AE says so)....in a Sealed alignment....Excursion owns all...(both in context of this experiment where all things else are equal).....
So...trying to applied my accumulated knowledge of so far....
Everything within xmax....
Both drivers in matching large Vented box tuned to 30hz? Spl level matched, we play 25hz..... I say it sounds "identical"....
Both in large Sealed box....Spl level matched we play 25hz..... I say it sounds "identical"....
So lets say I am over generalizing...where's the details...not trying to get into the other theile specs (unless we have too)...Fs would be my first go to...I would say that each driver is going to exaggerate the most at its free air resonance (be it that its position might be augmented by the box's compliance)...and then thats that....nothing else to see here...Or is there...
Diaphragm rigidity (I've tried to talk about several times to no avail) must not be a factor (anymore as of what? 2010?)....cause I haven't heard one person talk about it anywhere ever since I got back into design...but back in 1997....it was a thing. Lack of rigidity causes distortion in bass. I thought that was the hole purpose of the heavy diaphragm in the first place....lowering fs being a side affect.
How wrong am I?
100db at 20db....is just that...how can it sound different because its coming from another woofer if both woofers are within xmax/power/etc...Both are in similar volume boxes...you know how this goes for comparing different woofers....we try to removal as many variables as we can....
I remember comments pointing to fs...ok lets have it...the Ultimax has a fs of 19hz and the 18h+ has a free air resonance of 30hz... So what? In a vented alignment fc owns all (John of AE says so)....in a Sealed alignment....Excursion owns all...(both in context of this experiment where all things else are equal).....
So...trying to applied my accumulated knowledge of so far....
Everything within xmax....
Both drivers in matching large Vented box tuned to 30hz? Spl level matched, we play 25hz..... I say it sounds "identical"....
Both in large Sealed box....Spl level matched we play 25hz..... I say it sounds "identical"....
So lets say I am over generalizing...where's the details...not trying to get into the other theile specs (unless we have too)...Fs would be my first go to...I would say that each driver is going to exaggerate the most at its free air resonance (be it that its position might be augmented by the box's compliance)...and then thats that....nothing else to see here...Or is there...
Diaphragm rigidity (I've tried to talk about several times to no avail) must not be a factor (anymore as of what? 2010?)....cause I haven't heard one person talk about it anywhere ever since I got back into design...but back in 1997....it was a thing. Lack of rigidity causes distortion in bass. I thought that was the hole purpose of the heavy diaphragm in the first place....lowering fs being a side affect.
How wrong am I?
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Earl Geddes discussed some things to look for in a low frequency driver in this post, more details in the preceding thread like in this post.
The low frequency system he currently uses is sealed. In the past he used bandpass enclosures. He converted to sealed because he said it supplied better value in money and size.
The low frequency system he currently uses is sealed. In the past he used bandpass enclosures. He converted to sealed because he said it supplied better value in money and size.
If you read the link where Earl posted that information he is saying that amplifier clipping is a bigger problem and in commercial powered subs if pushed the amp will clip which is much more of an audible issue than what happens with over excursion of a woofer.
So having greater efficiency means that you need less power and are less likely to clip the amp.
For low frequencies volume displacement is the limiting factor.
So having greater efficiency means that you need less power and are less likely to clip the amp.
For low frequencies volume displacement is the limiting factor.
My experience with commercial amps driving separate subs, and self-powered speakers with integral amps, is exactly opposite to that....(prosound stuff).
Amp clipping on a sub has a much less negative effect on SQ, than over excursion...
I mean, they aren't even close to being in the same ballpark, unless maybe you're talking extreme abuse with constant continuous clipping.
Any run of the mill prosound amp,...all analog, or digital input, no matter....makes clipping less an issue than over excursion.
Heck, decent commercial self-powered subs don't allow over excursion to begin with.....
Maybe home audio amps are lacking decent clip limiters????
Or home audio self-powered subs lack functional power management???
Simply doesn't make sense to me.
Because your not seeing the point. If your amp has unlimited power then of course over excursion is going to be the bigger problem. Home use seldom use the mega power smart amps that pros use - that's the difference. Your talking pro and I'm talking DIY - not the same thing.
Of course I can design an amp that is the mirror of a specific driver and DSP control the SHiit out of it such that neither amp clipping or excursion limitations would be audible, but that's sci-fi not DIY.
Of course I can design an amp that is the mirror of a specific driver and DSP control the SHiit out of it such that neither amp clipping or excursion limitations would be audible, but that's sci-fi not DIY.
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I was only trying to explain the information quoted from Earl in relation to efficiency, amp power and excursion.
I have no real experience of clipping amps or over excursing woofers to speak on that topic I try to design systems for myself that have neither problem
Yes on both counts, pro equipment is very different to consumer stuff.
I think i am seeing the point. Or at least the point to me was which effects audibility the worst, amp clipping or over excursion.
No amp has unlimited power...I see clip lights all the time on subs.
And i hear over excursion too.
Over excursion is waaaay worse.
Imho, Audio is audio...be it DIY or pro.
Speaker management is speaker management...be it DIY or pro.
Dsp tools make all this readily available to DIY.
It's simple science, and it's DIY... but definitely not sci-fi
Some amps will clip more gracefully than others and it could also depend on exactly at what level the clip light has been set to. If I was making an amp I might set the light to come on just before true clipping.
The kind of over excursion issues you are hearing might not be quite the same as what Earl was describing so in a different use case or scenario the audible effects might be reversed.
The kind of over excursion issues you are hearing might not be quite the same as what Earl was describing so in a different use case or scenario the audible effects might be reversed.
I need to sit down and read whats been said...just remember, I follow what Geddes is saying and says....I started on this topic again because there were people around during the time before i purchased the 18h+ Basically saying that it was no good for a subwoofer or not a "real subwoofer" or only good down to 30hz....Maybe those people are gone now...