How to avoid letting the "Magic Smoke" out of my UB5's

[geeqner]

OK, I am well aware that with my new XPA-2 - I have the ability, should I so choose, to probably shoot the flaming remnants of my Voice Coils across the room, among other problems....

SPEAKERS:
The ELAC Primary Speakers that I am using are the Uni-Fi UB5 Series.
They are rated for:

     Sensitivity: 85 dB at 2.83 v/1m

     Recommended amplifier power: 40 to 140 wpc

     Peak power handling: 140 wpc

     Nominal impedance: 4 Ω; minimum 3.4 Ω

AMP: 
XPS-2, Gen3:
490 watts RMS/channel; THD<0.1%; 4 Ohms; two channels driven.
So, I probably have the ability to go almost 6dB ABOVE the maximum that the speakers are rated for
IIRC, ELAC states that the maximum Amplifier size for these speakers is 140 or 150 Watts (RMS) or it voids the Warranty

There is probably enough power here such that the speakers will probably exceed their maximum Wattage BEFORE the Amp goes into any sort of clipping.  Is this correct, or should I hear "warning signs" coming from the speakers that will tell me that I have entered the Danger Zone?

Knowing this - what safeguards does the Emotiva "Borg" advise in order to minimize the odds of requiring non-Warranty replacement of my speakers?
I know that most of the Volume Controls on Receivers / Pre-Amps use "Audio Taper" - so that the Volume seems to increase in a Linear manner, while it is actually providing EXPONENTIAL increases in power.  With this in mind - if I "safety" the Volume Control to about Halfway-Up, I am probably at well less than half-power.

Whadda'ya' think?

[emofrmcgy]

Common sense in the person operating the volume knob.

[KeithL]

The problem with any possible way of setting any sort of safety limit is that your Volume control sets the GAIN and not the power output.

So, let's assume that you set some sort of limiter that prevents you from turning the Volume up too high with your current input source.
If you then connect a new source that is LOUDER than your current one... at that same setting you will be putting out far more power.
And, if you connect a source with a lower output level, you'll run into your limit before the output is as loud as you want.
The situation is slightly better if you ONLY use digital inputs, because the output your digital processor will put out with a "0 dB full scale digital signal" is fixed (as long as you leave all the other settings alone).
However, ANALOG sources tend to vary pretty widely (and that includes the analog outputs of devices like DACs).

What you would really like is something that monitors the POWER being sent to the speakers directly - and limits it if necessary.
Unfortunately, because such devices always seem to have nasty audible side effects, you simply won't find one (either as a separate device or built into anything else).

You may not find this comforting... but your best bet is simply to pay attention to what you're playing and don't play it too loud.

Alternately, if you want to absolutely protect your speakers from excessive power levels, the most effective and least expensive solution is old school....
Get a pair of those inline fuse holders and put one in line with the speaker cable leading to each speaker (the ones that hold the little glass tube "25mm or 20mm Buss fuses".).
Fuses have a small amount of resistance, which will very slightly affect damping, but should not cause any sort of noise or distortion.
And, while turning the volume all the way up with no speaker connected isn't a great idea, blowing a fuse while playing music at normal listening levels would be perfectly safe for the amp.
(It would probably go into protect but it won't be damaged.)

Ignore the normal calculations for fuses - because there are time factors involved.
At that power level, I would probably start with a 2A FAST BLOW fuse.
Nothing can absolutely protect you from blowing a tweeter if you play something with a massive amount of heavy high-frequency content.
However, a fuse will protect you from most forms of "gentle abuse".... and won't have any really bad side effects.
(If you're really nervous... you could start with 1A fuses and see if they blow... and, if so, go up to 2A..... but USE FAST BLOW FUSES - AND *NOT* SLOW BLOW FUSES.)

(I've also got to say that this is the first time I've EVER heard of someone threatening to void your warranty if you use an amplifier that's too powerful.)

Mar 20, 2018 16:35:11 GMT -5 geeqner said:

OK, I am well aware that with my new XPA-2 - I have the ability, should I so choose, to probably shoot the flaming remnants of my Voice Coils across the room, among other problems....

SPEAKERS:
The ELAC Primary Speakers that I am using are the Uni-Fi UB5 Series.
They are rated for:

     Sensitivity: 85 dB at 2.83 v/1m

     Recommended amplifier power: 40 to 140 wpc

     Peak power handling: 140 wpc

     Nominal impedance: 4 Ω; minimum 3.4 Ω

AMP: 
XPS-2, Gen3:
490 watts RMS/channel; THD<0.1%; 4 Ohms; two channels driven.
So, I probably have the ability to go almost 6dB ABOVE the maximum that the speakers are rated for
IIRC, ELAC states that the maximum Amplifier size for these speakers is 140 or 150 Watts (RMS) or it voids the Warranty

Knowing this - what safeguards does the Emotiva "Borg" advise in order to minimize the odds of requiring non-Warranty replacement of my speakers?
I know that most of the Volume Controls on Receivers / Pre-Amps use "Audio Taper" - so that the Volume seems to increase in a Linear manner, while it is actually providing EXPONENTIAL increases in power.  With this in mind - if I "safety" the Volume Control to about Halfway-Up, I am probably at well less than half-power.

Whadda'ya' think?

[garbulky]

If it helps, most of the time you will be running at about 1-2 watts of power. (No Joke, that's all it takes). You can sometimes get in to several hundreds of watts for really loud peaks for very short periods of time. So, unless you are throwing a block party and overheating the voice coil or you are hearing audible signs of strain, then you should be okay.
.....unless you are party mode insane that is.

[405x5]

Mar 20, 2018 17:02:03 GMT -5 KeithL said:

The problem with any possible way of setting any sort of safety limit is that your Volume control sets the GAIN and not the power output.

So, let's assume that you set some sort of limiter that prevents you from turning the Volume up too high with your current input source.
If you then connect a new source that is LOUDER than your current one... at that same setting you will be putting out far more power.
And, if you connect a source with a lower output level, you'll run into your limit before the output is as loud as you want.
The situation is slightly better if you ONLY use digital inputs, because the output your digital processor will put out with a "0 dB full scale digital signal" is fixed (as long as you leave all the other settings alone).
However, ANALOG sources tend to vary pretty widely (and that includes the analog outputs of devices like DACs).

What you would really like is something that monitors the POWER being sent to the speakers directly - and limits it if necessary.
Unfortunately, because such devices always seem to have nasty audible side effects, you simply won't find one (either as a separate device or built into anything else).

You may not find this comforting... but your best bet is simply to pay attention to what you're playing and don't play it too loud.

Alternately, if you want to absolutely protect your speakers from excessive power levels, the most effective and least expensive solution is old school....
Get a pair of those inline fuse holders and put one in line with the speaker cable leading to each speaker (the ones that hold the little glass tube "25mm or 20mm Buss fuses".).
Fuses have a small amount of resistance, which will very slightly affect damping, but should not cause any sort of noise or distortion.
And, while turning the volume all the way up with no speaker connected isn't a great idea, blowing a fuse while playing music at normal listening levels would be perfectly safe for the amp.
(It would probably go into protect but it won't be damaged.)

Ignore the normal calculations for fuses - because there are time factors involved.
At that power level, I would probably start with a 2A FAST BLOW fuse.
Nothing can absolutely protect you from blowing a tweeter if you play something with a massive amount of heavy high-frequency content.
However, a fuse will protect you from most forms of "gentle abuse".... and won't have any really bad side effects.
(If you're really nervous... you could start with 1A fuses and see if they blow... and, if so, go up to 2A..... but USE FAST BLOW FUSES - AND *NOT* SLOW BLOW FUSES.)

(I've also got to say that this is the first time I've EVER heard of someone threatening to void your warranty if you use an amplifier that's too powerful.)

Mar 20, 2018 16:35:11 GMT -5 geeqner said:

OK, I am well aware that with my new XPA-2 - I have the ability, should I so choose, to probably shoot the flaming remnants of my Voice Coils across the room, among other problems....

SPEAKERS:
The ELAC Primary Speakers that I am using are the Uni-Fi UB5 Series.
They are rated for:

     Sensitivity: 85 dB at 2.83 v/1m

     Recommended amplifier power: 40 to 140 wpc

     Peak power handling: 140 wpc

     Nominal impedance: 4 Ω; minimum 3.4 Ω

AMP: 
XPS-2, Gen3:
490 watts RMS/channel; THD<0.1%; 4 Ohms; two channels driven.
So, I probably have the ability to go almost 6dB ABOVE the maximum that the speakers are rated for
IIRC, ELAC states that the maximum Amplifier size for these speakers is 140 or 150 Watts (RMS) or it voids the Warranty

Knowing this - what safeguards does the Emotiva "Borg" advise in order to minimize the odds of requiring non-Warranty replacement of my speakers?
I know that most of the Volume Controls on Receivers / Pre-Amps use "Audio Taper" - so that the Volume seems to increase in a Linear manner, while it is actually providing EXPONENTIAL increases in power.  With this in mind - if I "safety" the Volume Control to about Halfway-Up, I am probably at well less than half-power.

Whadda'ya' think?

2amp. Fast blow in line.....
That’s exactly what I did when I was “overpowering” a pair of speakers with no internal fusing.

My current (no pun intended) systems have bistable resistors in the crossover that limit the current and reset if excessive output is in play.

As all of us are saying, discretion with the volume control is all it takes....don’t overthink it!

Bill