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VU/Peak meter to save my speakers

I understand what you are trying to do and why you are trying to do it. But I believe your execution is a little off.

Power meters are a way to get a ROUGH IDEA as to amp output and they are eye candy to boot. They are not a tool to avoid clipping. Music is too dynamic and fast for a meter to pick it all up. They are NOT "clip detectors"....not by any stretch. By the time you see clipping, or output beyond the amps rated output on an analog power meter it is way too late.

The best way to stay away from clipping is to use an amp that is rated at twice the speakers continuous power handeling rating. Most jbl alnico speakers are rated at 75w, so I use 150wpc to power them. Then I use the Simpson 260 as a power meter to watch amp output to help avoid overpowering. And I like the eye candy.

It's far more practical to avoid overpowering with a big amp than to avoid clipping with a small amp.
"I understand what you are trying to do and why you are trying to do it. But I believe your execution is a little off"

That's nothing new. Lol

I agree that having an amp with the power output of twice the speakers rating, that's a pretty good rule of thumb for other things too. I picked up an Sakura AV-735 karaoke amplifier, it puts out 700w x 2 @ 8 Ohms and 1325 x 2 @ 4 Ohms. The power supply is 220v ac, we have 110 so I picked up a step-up/step-down transformer rated at 5000w.

That should be sufficient to run the Sakura, a tv monitor for karaoke and the 120w Yamaha Integrated Mixer EM Series Model 85 amp I power the monitor speakers with. At home I still need to upgrade a circuit for it as the circuit it's plugged into is still 15 amps. Should, according to my brother who is far more electronically literate than I, run a 25amp circuit for it. So far it hasn't really been an issue since I have rarely have pushed that amp more than around 1/4 volume and never more than 1/3 volume. However, I plan eventually to be taking it to gatherings where it it will be used outside in the open. Will probably need a bit more volume then
 
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This is true. I have to worry about the Marantz 2385 Cornwall 3 combo I have launching me out through the front windows into the street before I would have to worry about clipping. This receiver does have peak LEDs. Although I would really like to listen at about 90dB, I try to keep it to 80, and that's only 20% of the volume dial. It's like driving a muscle car with crappy tires.
I suddenly have Marantz envy! Been contemplating getting a big Marantz, love my 2215B (baby) Marantz. Can only imagine what the baby's big brother can do. I don't recall the exact model but my cousin in Arizona has one, I spotted it in the background in a photo he posted on Facebook. I asked him about it and he said he's not using it because the controls are scratchy, I suggested he either get it gone through and cleaned up or sell it to me. Haven't heard anything back about him being willing to sell yet.

That 2215 was my first receiver, got it at a pawn shop and carried it home on my bicycle several miles. My legs were fine but my arms were toast, it was worth the effort and I still have it decades later.
 
The best advice has been given. Use your ears.

Sure, one can get a big amp and push clipping down the road or try other means but if one still has their head up their arse one can still damage stuff.

Amps don't damage speakers, people do, when they don't yield to the signs of distress whether it be of the speaker or of the amp.
This is true, however I still like to know if an idea will work. Whether I use it or not is irrelevant, just wanted to know what others had to say about it. From what I have gathered, a meter can be a tool to help visualize what's going on between the amp and speakers. Bottom line though it seems, is that there is no substitute for what's going on between the ears and the brain
 
Ever heard of fuses? Usually 2 amp fast-blo for bookshelf, maybe 4 amp for towers.
Fuses won't tell you how much headroom the amplifier has left before clipping the waveform. And that's the info the op wants to have available to him while blasting away.
 
Fuses won't tell you how much headroom the amplifier has left before clipping the waveform. And that's the info the op wants to have available to him while blasting away.

A low value fuse will stop that before that happens. Speakers don't blow because they produce distortion, they blow because they received too much current, causing voice coils to get hot, warp and die.
 
A low value fuse will stop that before that happens. Speakers don't blow because they produce distortion, they blow because they received too much current, causing voice coils to get hot, warp and die.
Last I checked the voice coil will go open to protect the fuse about 1/2 the time.

They are a good addition to an amp that has no protection circuitry to monitor dc at the outputs etc. because something is better than nothing......but that's about it.
 
Speakers don't blow because they produce distortion, they blow because they received too much current, causing voice coils to get hot, warp and die.
Yes, that's certainly one failure mechanism, but it isn't the only one. Wires can also break. Also, the voice coil can get slammed into the magnet and bent.
 
I don't need no stinkin meter.

I hooked up my Boogie Lights off my Harley. Getting it through the doorway to listening post was a little challenging but it was an old carpet that needed replacing anyway.

They pulse to the beat of the jams AND change colors. Does anyone know how to calibrate them to flash blue when I'm grooving on the blues?
 
I'm sure some people use slo-blo or the wrong value to keep themselves from hurting....themselves.

Self control is still the best. As others have pointed to- if something sounds distorted at a particular volume, something in the chain has gone beyond its peak.

Exactly.
A little common sense and self control go a long ways.

Let's just say the OP decides he can control his volume levels and turn it down if it sounds distorted or his receiver/amp is running hot.
I suppose he could still install some sort of kludge for any situations where alcohol, guests, or a combination of both might cause possible speaker damage.
 
Exactly.
A little common sense and self control go a long ways.

Let's just say the OP decides he can control his volume levels and turn it down if it sounds distorted or his receiver/amp is running hot.
I suppose he could still install some sort of kludge for any situations where alcohol, guests, or a combination of both might cause possible speaker damage.

Yes, that makes sense. other people like to "invent" reasons why the common sense mode doesn't work, "or lets use gum wrapper" to replace a fuse. I guess bad decisions are made daily......
 
Yeah, in practice it's not as simple a form of speaker insurance as I was hoping for. The power meter I think, if used with the power output capacity of the amp and the power handling capabilities of the speakers in mind would give a reasonable ball park visualization of when you are getting close.

...

Once you hear it...you will understand what everyone is trying to tell you in this thread. When the sound gets muddy and/or harsh and those conditions are alleviated by turning down the volume, that is the distortion, either from the amp and/or the speakers, that you want to avoid. It is possible that some of us learned this the hard way...in younger years perhaps....by blowing up components. If you haven't done that yet, you could be well on your way :) But like I said, once you hear it, you will know it and then you will stop obsessing about meters for any purpose other than their real one...which is eye candy.

The approach you are wanting to implement seems logical given that meters exist and speaker power ratings exist. But the ability to use these things in a useful way, at least in a precise and useful way, is an illusion. For one, the calibration issues already mentioned several times. That and distortion happens in both speakers and amps and even if by using meters to avoid amplifier distortion, you still need your ears to be listening for speaker distortion.
 
Yes, that makes sense. other people like to "invent" reasons why the common sense mode doesn't work, "or lets use gum wrapper" to replace a fuse. I guess bad decisions are made daily......
I don't think anyone is really arguing against common sense.

It just boils down to how it is implemented. Is it best to under power and use common sense to avoid clipping the amp or is it best to overpower and use common sense to avoid over excursion etc.?
 
It's actually best just to use common sense (presuming that means listening to what the components are telling you) without any other qualifiers. It works with every combination, doesn't require any different gear, no "special sauce", no tricks, etc.
 
I have a meter unit in my system. It's quite sophisticated and the service manual has detailed calibration instructions. It can look at signal flow before the power amp and output power from the amp. VU is on the top scale and power output is on the bottom scale. My Klipsch speakers rarely see more than one watt. Fortunately the sensitivity can be switched. You can set the display for average, peak and peak hold.

Don't see these very often but it covers a lot of ground. I actually use it to see when my stylus needs to be cleaned. Channel imbalance usually shows up before audible distortion.
Technics SH-9020.png
 
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