I've looked at some articles about normalizing line level output voltage. Most aproaches require modifying mp3 file.
ITunes has built in feature to normalize volume level.
Some mp3s for some reason have rediculous output volume. Twice the norm.
I am setting up home audio system for a bar restaurant.
Everyone will be using their mp3, iphone, android via dragonfly audioquest DAC. Latest one red.
I Would Like To add A microphone or some SPL, decibel meter Near speakers and Display this information by receiver or amplifier. Speakers will be about 50-60 feet away from receiver amps.
Basically I want to avoid a chance of over driving speakers. Of course I'll put a red marker on volume knob or adjust gains on power amps.
One of the amps has power meter indicators. Yamaha m60.
The idea is to basically have the speakers at 50-70% of their max volume capability.
ITunes has built in feature to normalize volume level.
Some mp3s for some reason have rediculous output volume. Twice the norm.
I am setting up home audio system for a bar restaurant.
Everyone will be using their mp3, iphone, android via dragonfly audioquest DAC. Latest one red.
I Would Like To add A microphone or some SPL, decibel meter Near speakers and Display this information by receiver or amplifier. Speakers will be about 50-60 feet away from receiver amps.
Basically I want to avoid a chance of over driving speakers. Of course I'll put a red marker on volume knob or adjust gains on power amps.
One of the amps has power meter indicators. Yamaha m60.
The idea is to basically have the speakers at 50-70% of their max volume capability.
It will be the crew of the place. Not well versed in audio use. So they'd need to see the number and adjust volume accordingly. They can't ear ball.."that's pushing the speakers" can't hear woofer bottomING out
You need a measuring microphone and a software that calculates Sound Exposure Level (A-weighted).
I see. Any all in one kits available? I see some decibel meters online. Some have a-weighted option.
Was thinking of disassembling one and extending microphone closer to speakers . Solder long wires between microphone and meter
General Tools Digital Sound Level Meter with Analog Bar Graph DSM8930 at The Home Depot - Mobile
A quick search brought up this Android app:
https://play.google.com/store/apps/details?id=com.dom.audioanalyzer
I tried it myself, and found that the LAS function can be best used for measuring average sound levels.
https://play.google.com/store/apps/details?id=com.dom.audioanalyzer
I tried it myself, and found that the LAS function can be best used for measuring average sound levels.
Last edited:
But speakers will be on the ceiling.
30 feet up. Maybe I could use this app and get a microphone hanging closer to speakers. On one of the lightings.
Edit.
Looks like sensitivity is adjustable there. Thanks for this tip. I appreciate
Last edited:
You do NOT need any SPL meter 🙂
Since you always use the same speakers, what you need is to fix maximum *amplifier* output.
That some MP3s sound louder than others, physically means that played through the same system some will produce higher Audio *voltage* than others, so you need to control this and output SPL will also be controlled.
Again, if different operators set volume controls to different levels according to personal taste, they are also adjusting to different voltage levels, again what you need to control.
There are kits and schematics available, but since I presume you are not doing this for fun or practice b ut to solve a concrete problem in a Restaurant/Bar which is already running (or close to opening), buy a ready made one.
The first 5 or 6 ones in this list are very good, no need to spend a ton.
If you want classic tried and true, go straight to DBX.
https://www.sweetwater.com/c466--Compressors_Limiters/low2high
Basic operation and assuming a certain output voltage/power lever, you pick the one *you* find comfortable.
Suppose you want to set power so each speaker cabinet gets no more than 50W RMS.
That means 20V RMS if cabinets are 8 ohms each, most common impedance; you adjust it if some are, say, 4 ohms.
You inject a 1kHz or 440Hz audio tone in the system (from, say, a smartphone or MP3 player) .
Download it from here: Download Audio Tone Files
download the 30 second MP3 you like, set player to "repeat" or "repeat one" so it gets played continuously.
Audio chain will be : Smartphone > USB DAC > Notebook? > maybe some sound mixer or desk or preamp > **LIMITER** > Power amp(s) > speaker(s)
If the power amp has a VU/power meter, look at the 50W mark; if not, connect a multimeter set to 200VAC at speaker out terminals, all meters work well up to 400Hz and most not bad at 1kHz, so you can trust what they show.
Play the MP3 continuous tone, rise volume until you get 20V RMS or 50W shown, then slowly set Limiter threshold control so it *just* starts lowering output.
Go back forth a couple times so you confirm you set the right limiting threshold, then check Limiter operation by rising volume sent into it: output volume must not change, or very little.
Presto! ... no heavy handed operator (or louder than normal MP3) can send more than 50W into that speaker.
Same applies to all other speakers driven from that limiter.
I have designed, built and installed hundreds of amplifiers with similar limiters, built-in, for Restaurants, Theatres, Hotel Lobbies, Meditation Centers, even Guri Maharaj Ji Ashrams, where sound level must be *tightly* controlled, and systems are run by untrained operators.
Some have been set as low as 2 to 5W RMS max. , because situation requires that .... nobody wants deafening "Meditation Music" !!!!
Since you always use the same speakers, what you need is to fix maximum *amplifier* output.
That some MP3s sound louder than others, physically means that played through the same system some will produce higher Audio *voltage* than others, so you need to control this and output SPL will also be controlled.
Again, if different operators set volume controls to different levels according to personal taste, they are also adjusting to different voltage levels, again what you need to control.
There are kits and schematics available, but since I presume you are not doing this for fun or practice b ut to solve a concrete problem in a Restaurant/Bar which is already running (or close to opening), buy a ready made one.
The first 5 or 6 ones in this list are very good, no need to spend a ton.
If you want classic tried and true, go straight to DBX.
https://www.sweetwater.com/c466--Compressors_Limiters/low2high
Basic operation and assuming a certain output voltage/power lever, you pick the one *you* find comfortable.
Suppose you want to set power so each speaker cabinet gets no more than 50W RMS.
That means 20V RMS if cabinets are 8 ohms each, most common impedance; you adjust it if some are, say, 4 ohms.
You inject a 1kHz or 440Hz audio tone in the system (from, say, a smartphone or MP3 player) .
Download it from here: Download Audio Tone Files
download the 30 second MP3 you like, set player to "repeat" or "repeat one" so it gets played continuously.
Audio chain will be : Smartphone > USB DAC > Notebook? > maybe some sound mixer or desk or preamp > **LIMITER** > Power amp(s) > speaker(s)
If the power amp has a VU/power meter, look at the 50W mark; if not, connect a multimeter set to 200VAC at speaker out terminals, all meters work well up to 400Hz and most not bad at 1kHz, so you can trust what they show.
Play the MP3 continuous tone, rise volume until you get 20V RMS or 50W shown, then slowly set Limiter threshold control so it *just* starts lowering output.
Go back forth a couple times so you confirm you set the right limiting threshold, then check Limiter operation by rising volume sent into it: output volume must not change, or very little.
Presto! ... no heavy handed operator (or louder than normal MP3) can send more than 50W into that speaker.
Same applies to all other speakers driven from that limiter.
I have designed, built and installed hundreds of amplifiers with similar limiters, built-in, for Restaurants, Theatres, Hotel Lobbies, Meditation Centers, even Guri Maharaj Ji Ashrams, where sound level must be *tightly* controlled, and systems are run by untrained operators.
Some have been set as low as 2 to 5W RMS max. , because situation requires that .... nobody wants deafening "Meditation Music" !!!!
Agree with Juan^^^
A limiter does the job.
The volume control on an amplifier is not a power setting. Turning the volume up half way on a 100 watt amp does not limit power to 50 watts, for example. If you turn me down half way, all I have to do is play louder and we are back where we started.
There is a reason most commercial establishments do not use home stereos. That is why they make commercial equipment - it is designed for the job.
Since this is a restaurant, are we talking "ceiling speakers"? the round flat grilled in the suspended ceiling panels? Or is this more of a night club with a pair of loud speakers - I mean speakers playing loud. A pair of speakers is one thing, but if you have an array of 8-10-12 inch speakers up there like many places, then they are probably wired for "constant voltage" - also called "70 volt" wiring. Your home stereo will not be ready for that.
A limiter does the job.
The volume control on an amplifier is not a power setting. Turning the volume up half way on a 100 watt amp does not limit power to 50 watts, for example. If you turn me down half way, all I have to do is play louder and we are back where we started.
There is a reason most commercial establishments do not use home stereos. That is why they make commercial equipment - it is designed for the job.
Since this is a restaurant, are we talking "ceiling speakers"? the round flat grilled in the suspended ceiling panels? Or is this more of a night club with a pair of loud speakers - I mean speakers playing loud. A pair of speakers is one thing, but if you have an array of 8-10-12 inch speakers up there like many places, then they are probably wired for "constant voltage" - also called "70 volt" wiring. Your home stereo will not be ready for that.
> But speakers will be on the ceiling.
So? If it is loud at the ceiling, it will be loud on the floor. Maybe louder close to the speaker. But in many rooms the reverberant level is nearly uniform once you get more than 4 to 8 feet away from a source.
As has been said, monitoring the amplifier level gives a similar metric.
Any broadband measure will NOT protect speakers. Huge power is safe 100Hz-1KHz (typically); the same power below 50Hz or over 3KHz is short life. Most speech/music falls in the midrange. But if "anybody" can play "any" track, some strange stuff may get put through the system.
OVER-buy the speakers.
I recently saw some fairly expensive systems (being sold to a church but more suited for high-end clubs) where the 3,000 Watt amplifier had complex speaker-specific protection in it. My judgement was that it could be blowout-proof. (It would just throttle-back, not blow its guts out.) But I'm long out of that racket, didn't even save the proposal.
So? If it is loud at the ceiling, it will be loud on the floor. Maybe louder close to the speaker. But in many rooms the reverberant level is nearly uniform once you get more than 4 to 8 feet away from a source.
As has been said, monitoring the amplifier level gives a similar metric.
Any broadband measure will NOT protect speakers. Huge power is safe 100Hz-1KHz (typically); the same power below 50Hz or over 3KHz is short life. Most speech/music falls in the midrange. But if "anybody" can play "any" track, some strange stuff may get put through the system.
OVER-buy the speakers.
I recently saw some fairly expensive systems (being sold to a church but more suited for high-end clubs) where the 3,000 Watt amplifier had complex speaker-specific protection in it. My judgement was that it could be blowout-proof. (It would just throttle-back, not blow its guts out.) But I'm long out of that racket, didn't even save the proposal.
It will be 2 vienna acoustics beethoven
And 2 bowers and wilkins dm604 s3
Amps are yamaha mx1 , yamaha m60 (with power meters)
Both have gain control. I could also sort of play various tracks and looking at woofer movement and hearing the speakers set them to 50% of their capacity.
It's back ground music, radio. Feel happy atmosphere.
Pretty sure gains on these amps limit how much voltage these amps output.
And 2 bowers and wilkins dm604 s3
Amps are yamaha mx1 , yamaha m60 (with power meters)
Both have gain control. I could also sort of play various tracks and looking at woofer movement and hearing the speakers set them to 50% of their capacity.
It's back ground music, radio. Feel happy atmosphere.
Pretty sure gains on these amps limit how much voltage these amps output.
> vienna acoustics beethoven
In a bar ???
When those get trashed, go to the rock-band shop for a nice $900 pair of 3-way stage speakers. Some really are quite good, even before beer.
In a bar ???
When those get trashed, go to the rock-band shop for a nice $900 pair of 3-way stage speakers. Some really are quite good, even before beer.
^You forget, this is a high class establishment, "rich people driving nice cars"..............
Last edited:
It's pretty loud actually. More than plenty. At 1030-11 o'clock volume level.
2 vienna acoustics beethoven
2 bw dm604 s3
2 jvc sx-a3.
I doubt u will find such refined sound in such big spaces anywhere in the world. Their other option was regular ceiling speakers. With install fees it was many times more than going with vienna, bw and jvc speakers.
And mediocre ceiling speakers would make yet another restaurant, nothing special
Looking into voltage limiters mentioned.
And have some questions:
1)
On some home audio amps there are input level knobs.
Aren't these voltage limiters already?
Won't allow more than .5V into the amp.
Yamaha mx1 for some reason calls them gains. On m60 yamaha it's input levels
2) do 1/4" inputs on pro audio gear expect same higher voltage of xlr (around 4volts) or they are unbalanced and work in 2v range
And an update there will be 1-3 people operating the system. And it's family oriented refined spot. Not a rave or concert venue.
2 vienna acoustics beethoven
2 bw dm604 s3
2 jvc sx-a3.
I doubt u will find such refined sound in such big spaces anywhere in the world. Their other option was regular ceiling speakers. With install fees it was many times more than going with vienna, bw and jvc speakers.
And mediocre ceiling speakers would make yet another restaurant, nothing special
Looking into voltage limiters mentioned.
And have some questions:
1)
On some home audio amps there are input level knobs.
Aren't these voltage limiters already?
Won't allow more than .5V into the amp.
Yamaha mx1 for some reason calls them gains. On m60 yamaha it's input levels
2) do 1/4" inputs on pro audio gear expect same higher voltage of xlr (around 4volts) or they are unbalanced and work in 2v range
And an update there will be 1-3 people operating the system. And it's family oriented refined spot. Not a rave or concert venue.
Last edited:
They are voltage limiters only in the sense that they limit the expected line level output of typical sources. If the line level device (or headphone amplifier output of a portable device) has higher output than typical, they will allow higher output from the amplifier. So, they will not do what you want, except perhaps accidentally.
To use your numbers, a typical non-digital line level device will output perhaps 750mV. Using the settings you think would limit the input to 0.5V (500mV) they will indeed do so, but substitute another device (like a CD player with a 2.0V output) they will only reduce the level by the same 250mV as they would with the 750mV device ... so you would have 1.75V (1750mV).
No resistive pot or switch (which is what these amps have) will do anything else, and these level controls are not of the type outlined by others earlier in this thread, which offer good advice that you should heed, if your goal is truly as you say it is.
Output of the headphone amplifier (via the 2.5/3.5mm phone jack) on smartphones and iPod-like devices is not the same as line level which might be available from the device (eg on most iPods via the 30-pin connector on the bottom), and that output is heavily dependent on the impedance of your amplifier's inputs.
Consumer and Pro levels differ, with 0Vu on meters with pro gear corresponding to a higher level than 0Vu on consumer gear. (+4 dBV vs -10 dBV = 11.79dB, not 14dB as it might seem at first glance). But if your source is not true Pro Level (and won't be with any consumer variant, even if XLR connectors are present) that won't matter. Also the 2V output of digital devices (disk players, etc) matches neither, and is higher than Pro Level in any case.
Reference data:
0dBu = 0.775 volts AC with an untermninated load.
0dBv = 0.775 volts AC into a 600ohm load.
0dBm = 1milliwatt at 0.775 volts AC into a 600ohm load.
-10Vu = 316mV rms
+4Vu = 1.228V rms
Respectfully, if you don't intend to take the correct and reasonable advice already offered to you freely and sincerely, just say so and we can do something else.
Last edited:
This exact same question was asked in other thread http://www.diyaudio.com/forums/pa-systems/307824-long-wire-run-4ohm-speakers-100-150-feet-wire.html by the same person, same speakers and situation: trying to install "2 vienna acoustics beethoven + 2 bw dm604 s3 + 2 jvc sx-a3" in a "rich people Restaurant" , same suggestions were offered, and then the OP casually mentioned "now and then the place will be used to hold Wedding Parties but no more than 3 continuous hours Dance Music will be needed" at which point he was suggested to *forget* Hi Fi speakers for such use.
And to use limiters or straight buy powered speakers which already include them.
If now he still insists on his original idea, nothing useful will be achieved, so why waste time here?
Every useful suggestion has already been said, many times.
And to use limiters or straight buy powered speakers which already include them.
If now he still insists on his original idea, nothing useful will be achieved, so why waste time here?
Every useful suggestion has already been said, many times.
- Status
- Not open for further replies.