Getting above 92dB

[Gordon Gray]

Let's not get too serious about 92db at peaks. Damaging hearing at 92db is generally accepted statement (OSHA allows 8 hours of exposure to 90 dBA) and for prolonged exposure to such SPL. Keep in mind that even when you walk on busy city streets you may be exposed to much higher SPL peaks. Are you guys saying that musicians are deaf because of "prolonged exposure" to live, not amplified concert. In NYC philharmonics I measured peaks quite above 100db!! (107db if my memory serves me well - "pictures at exhibition" sitting at about 20th row from orchestra).

92 db peak, for short periods, is not going to damage your hearing.

Having a room where you can sustain 120db without room overload, is an entirely different proposition.

GG

 

[TubeHeaven]

25' ceiling...what are you in an airplane hanger? ....low frequencies are at their best in huge enclosed spaces. I own a HIFACE M2TECh I am replacing soon as I don't think it's that great. I'd try to reducing the bass with the EQ if you are using iTunes as it really isn't very good at all. Look for a better digital interface. iTunes is so very veiled and non-audio friendly

 

[Bevensee]

Let's not get too serious about 92db at peaks. Damaging hearing at 92db is generally accepted statement (OSHA allows 8 hours of exposure to 90 dBA) and for prolonged exposure to such SPL. Keep in mind that even when you walk on busy city streets you may be exposed to much higher SPL peaks. Are you guys saying that musicians are deaf because of "prolonged exposure" to live, not amplified concert. In NYC philharmonics I measured peaks quite above 100db!! (107db if my memory serves me well - "pictures at exhibition" sitting at about 20th row from orchestra).

Correct me if I'm wrong....

92 dB measured with an iphone app is most likely a lot more than 92 dB peak. Probably closer to 92 dB average.

BTW. tinitus is quite common among classical violinists.

In any case, I think we all just wanted to advise the thread opener to be cautious with his hearing. That's all..

 

[Bevensee]

Not sure about impedance being invariant in bridged mode for amp. You will need to check.


J

I seem to remember reading somewhere that the tolerance of low impedance gets worse when bridging, but I am far from sure...

 

[User211]

For some more practical feedback, I used to run my Ascents in a 12 by 28 by 10ft room, using an 80 Watt Air Tight ATM2. Not 25 ft high I grant you, but the amp wasn't really capable of very high volume without showing signs of stress.

I've just sold a Parasound A21 that I kept for about 9 months. For massive power (450+ Watts into 4 Ohms) at not much money, especially 2nd hand, recommended if you can handle a very, very clean sound. Just shove a tube pre in front of it for some added colour if it comes across as "too sterile".

 

[Sky Saw]

25' ceiling...what are you in an airplane hanger? ....low frequencies are at their best in huge enclosed spaces. I own a HIFACE M2TECh I am replacing soon as I don't think it's that great. I'd try to reducing the bass with the EQ if you are using iTunes as it really isn't very good at all. Look for a better digital interface. iTunes is so very veiled and non-audio friendly

I'm using a Hiface2, which I find vastly better than using a TosLink optical cable. For the front end, I'm using Amarra HiFi; coming from having low expectations from a computer-based system, I'm impressed with the sound. It's not as good overall as my Meridian G08, but the dynamics on well-recorded 24-bit files are unbelievable. What are you looking at replacing the HiFace with?

 

[Sky Saw]

For some more practical feedback, I used to run my Ascents in a 12 by 28 by 10ft room, using an 80 Watt Air Tight ATM2. Not 25 ft high I grant you, but the amp wasn't really capable of very high volume without showing signs of stress.

I've just sold a Parasound A21 that I kept for about 9 months. For massive power (450+ Watts into 4 Ohms) at not much money, especially 2nd hand, recommended if you can handle a very, very clean sound. Just shove a tube pre in front of it for some added colour if it comes across as "too sterile".

I appreciate all the practical suggestions given so far. I'm going to try the blankets-behind-the-panels trick as soon as I have a chance. If that doesn't seem to solve my issue I'll see if I can lay my hands on a bigger amp.

I understand the idea behind horizontal bi-amping, but I don't understand the benefit of bridging over sending separate amplifier signals to the lower and upper speaker binding posts.

 

[amey01]

In any case, I think we all just wanted to advise the thread opener to be cautious with his hearing. That's all..

Absolutely. "Think", "might", "probably" and "most likely" are not good enough when it comes to hearing. You can't say "oh dear, that was too loud, I won't do that again".

When your hearing is gone it is gone for good. Done. Complete. Irreversable. Final.

 

[Sky Saw]

Absolutely. "Think", "might", "probably" and "most likely" are not good enough when it comes to hearing. You can't say "oh dear, that was too loud, I won't do that again".

When your hearing is gone it is gone for good. Done. Complete. Irreversable. Final.

It's good to be reminded. Playing music and listening to it is one of my greatest pleasures in life - I would hate to lose it.

 

[Sky Saw]

Just got out my trusty old (like 23 year-old) Radio Shack spl meter to compare with my iPhone app. The iPhone app was showing readings about 5bD higher than the Radio Shack meter while playing a a 'cello sonata with a baroque orchestra (mostly midrange stuff). I do notice that the iPhone app meter basically ignores bass energy, but appears to be more sensitive to the mid and upper frequencies.

 

[amey01]

Just got out my trusty old (like 23 year-old) Radio Shack spl meter to compare with my iPhone app. The iPhone app was showing readings about 5bD higher than the Radio Shack meter while playing a a 'cello sonata with a baroque orchestra (mostly midrange stuff). I do notice that the iPhone app meter basically ignores bass energy, but appears to be more sensitive to the mid and upper frequencies.

Are they both calibrated to the same scale? "A" or "C"?

 

[Gordon Gray]

Just got out my trusty old (like 23 year-old) Radio Shack spl meter to compare with my iPhone app. The iPhone app was showing readings about 5bD higher than the Radio Shack meter while playing a a 'cello sonata with a baroque orchestra (mostly midrange stuff). I do notice that the iPhone app meter basically ignores bass energy, but appears to be more sensitive to the mid and upper frequencies.

Sky,

As you know, a 5db discrepancy is huge.

+1 on Adam's comment. Need to use "C" weighting for equivalent SPL.

GG

 

[RUR]

Historically, iPhone microphones have rolled off dramatically below 200Hz. Can't easily find any evidence that this has been corrected in the iPhone 5.

http://blog.faberacoustical.com/2010/ios/iphone/iphone-4-audio-and-frequency-response-limitations/

 

[JonFo]

^^^ Which is why one should pay the bucks for the Studio6 Digital Audio Tools app: http://www.studiosixdigital.com/audiotools/

It has built-in calibration files that compensate for the avg profile of each model of iDevice.

 

[daniel]

Your 4070se has no problem driving low impedance ( less than 2 ohm). However, if it's bridged it's true that it ( they) wont be able to reach that low.