Understanding midrange driver output capability

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#24
To properly answer that question you need to hear both the SS and B&C with well executed crossovers. Maybe they would sound different but maybe not better or worse just different. A good high efficiency driver have a more snappy feel even at low SPL ime (and the 5mdn38 is a good one), although the 15M is fairly high eff amongst the home drivers. And at high DPL, there would be no question imo.

Maybe someone have real experience to share here.
 
#25
Have you ever listened to music or film at 110 dB? perhaps you have, but that is higher than rock concert SPL. 15 seconds of 110 dB makes my ears ring for 10 minutes or more.

Before you decide that you really need 110 dB capability, you should try exposing yourself to 110 dB. Turn on a large power tool, move your mobile phone closer until the dB-meter-app says "110 dB", then remove your hearing protection and put your face in the same spot as the mobile phone.
 
#26
I think all along skogs has said 110dB is only for transient peaks...that he does not at all expect to listen that loud on average.

I'd say, that's a decent number to shoot for.
I use 18dB as the peak to average spec.
So 110dB now becomes 92dB.
And that's at 1m.
I typically listen, watch, at about 4m.
So knock another 12dB off, and now we're at 80dB, average to the ears.
No risk to hearing imo. And good strong sound.
 
#27
As previously mentioned, I just want to be sure that my system can handle thx reference level, Which specifies 105db peaks from each speaker at the listening position. I typically go for 5 dB below reference level, but it's nice to have the full experience every once in awhile. The midrange I'm looking for will in combination with a tweeter replace my current PH2380 horn.

I used to work at a testing facility for 10MW+ engines, so I am aware of the dangers of sustained high SPL's. I think I have been confusing people with the 110db/1m requirement. I don't listen at anywhere near those levels sustained at the listening position. 10 seconds of 110db is insane.
 
#28
mark100 said:
I think all along skogs has said 110dB is only for transient peaks...that he does not at all expect to listen that loud on average.

I'd say, that's a decent number to shoot for.
I use 18dB as the peak to average spec.
So 110dB now becomes 92dB.
And that's at 1m.
I typically listen, watch, at about 4m.
So knock another 12dB off, and now we're at 80dB, average to the ears.
No risk to hearing imo. And good strong sound.
Click to expand...

Thank you!
 
#32
skogs said:
As previously mentioned, I just want to be sure that my system can handle thx reference level, Which specifies 105db peaks from each speaker at the listening position. I typically go for 5 dB below reference level, but it's nice to have the full experience every once in awhile. The midrange I'm looking for will in combination with a tweeter replace my current PH2380 horn.

I used to work at a testing facility for 10MW+ engines, so I am aware of the dangers of sustained high SPL's. I think I have been confusing people with the 110db/1m requirement. I don't listen at anywhere near those levels sustained at the listening position. 10 seconds of 110db is insane.
Click to expand...

It sounds like you have a good understanding of what 110 dB really is. Your requirements (THX) seem reasonable.

Cone/dome drivers can typically absorb transient power well above their power rating, as long as you don't run out of voice coil travel.

In my opinion, you should consider one of the high efficiency drivers discussed in the above posts... if you want to stay with this 4 inch SB driver, you should use two of them as MTM.
 
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#34
Re your CC, see pic below for an acceptable way to mount an MTM combination in a more narrow profile.

Not exactly sure how you are going to add in a 15" woofer with such limited vertical space too though.....
 

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#35
YSDR said:
So you say "sound quality" is not good with pro sound drivers? I don't think that's true. Of course there are pro drivers that are not so good for home hifi, but there are home hifi drivers that are not so good for that task either.
But for very high SPL, there are only few home hifi drivers that are up to the task, and these are not the smaller ones that you are after, imo.
Click to expand...

Not what I said, my remarks were strictly for the 5MDN38-8, though did [strongly] imply that any [super] stiff compliance normally only used for horn and OB apps without a correspondingly powerful motor to offset it combined with a lower Fs will be a poor choice for the OP's app in general, including accurately tracking the signal at low power relative to the driver's max 'music' power and especially during up to [Xmax +] peak power transient bursts.

Right, and why I showed earlier that a 6.5" should be at minimum, though historically I've used the pioneer's preferred 8".

GM
 
#36
Okay, sorry GM! I don't think I understand properly what you want to say with the signal tracking and so, but... maybe.
The OP wants a midrange and using that with heavy filtering (high and low-pass too). So a stiff suspension driver (with filtering) is not good for that task because it not tracks the signal properly at lower level?
Maybe I don’t have the expertise as yours, but I don’t see the connection.

Yeah, I recommended a 6.5" or 8" driver earlier too.

What do you say GM, what would be the sound signature of the bad signal tracking?
 
#38
Thanks Allen! At least we have some theoretical clue for the stiff suspension.

Moreover I don't understand the formula that GM wrote earlier:

"~[300*2500]^0.5 = ~866 Hz mean = ~34400/pi/866 = ~12.65 cm dia. = ~ 6.5" frame"

What is this for?
 
#40
"It's about sizing the cone to the passband."
Yet an another dry, theoretical thing, although I see the logic now. But for what kind of crossover slopes is this for, baffle step loss included, or it doesn't matter?

Edit: I see, it's for 2pi radiaton.
 
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