Can I damage my cab by playing too loud too low?

[jjl5590 15]

Hi all,

So I've got a TC RH750 paired with a TC RS212. I've just updated my HX Stomp with the 3.0 update and have been playing around with the poly effects. 

I really like the sound I can get with the poly pitch turned down -24 octave, playing around the 12th fret gives a really cool double-bass sound.

Working through the effects, I coupled it with a Teemah distortion and a few other blocks. Sounded really nice. Turned the volume up and started blasting out that lovely low-end, to the point my ears were actually starting to feel a bit weird, like there was pressure in them (a bit like on a plane or going through a tube tunnel).

This lead me to wonder, could I possibly do any damage to the paper speaker cones of my cab by playing at such a low octave at high volume? Could it rupture them?

Cheers for any advice

[Bill Fitzmaurice 761]

It's possible. You also could fracture the voice coil. PA subwoofers are designed to handle that usage, but standard electric bass cabs are not.

[Bolo 790]

Sounds like you are doing some damage to your ears. 

[Baloney Balderdash 322]

Yes you can!

As Bill suggested, if you use this a lot and like going that low, maybe get a crossover filter (cutting out the ultra low end from the signal fed to your bass cab and feeding it to a subwoofer instead) and a subwoofer, which are designed to handle those ultra low frequencies. 

Also if you are feeling pressure in your ears it's time to wear earplugs, or if you already do get some that dampens the sound level even more.

Edited November 26, 2020 by Baloney Balderdash

[BassmanPaul 96]

A HPF would give you some room for safety. You certainly can destroy your speakers by overloading them at low frequencies.

Edited November 26, 2020 by BassmanPaul

[owen 1,252]

Don't worry. You can buy new speakers. Your ears are another matter......

[jjl5590 15]

Thanks for the info, I'll make sure to use a HPF

[Woodinblack 4,325]

From what I see on the net the power amp on the RH750 has a HPF (not the preamp), to keep the lows out. As the RH750 produces less power than the RS212 speakers rating, I am not sure it would be possible to damage it. Not something I would worry about. However, if the sound made your ears funny, that is certianly something to worry about.

[Sparky Mark 253]

 

4 hours ago, Woodinblack said:

From what I see on the net the power amp on the RH750 has a HPF (not the preamp), to keep the lows out. As the RH750 produces less power than the RS212 speakers rating, I am not sure it would be possible to damage it. Not something I would worry about. However, if the sound made your ears funny, that is certianly something to worry about.

An HPF doesn't make a system idiot proof. Over excursion might still happen at frequencies above the cut off at very high volumes. Just sayin', no offence intended. 😇

[Woodinblack 4,325]

no offence taken but the output rating of the RH750 is, as people will spout with an almost religious passion if you dare to like them, less than 300W, so into a 400W speaker you should be able to run it flat out at any frequency for hours on end (which wouldn't happen with playing) without it going close to the Kenny Loggins zone.

[Sparky Mark 253]

14 minutes ago, Woodinblack said:

no offence taken but the output rating of the RH750 is, as people will spout with an almost religious passion if you dare to like them, less than 300W, so into a 400W speaker you should be able to run it flat out at any frequency for hours on end (which wouldn't happen with playing) without it going close to the Kenny Loggins zone.

I'm confident that I could destroy any 400W (thermal rating) bass cab with a 300W RMS output bass amplifier with irresponsible EQ settings. 

[Lfalex v1.1 702]

21 minutes ago, Sparky Mark said:

I'm confident that I could destroy any 400W (thermal rating) bass cab with a 300W RMS output bass amplifier with irresponsible EQ settings. 

Definitely this. Its when the power amp stage starts to clip that even relatively low powered amps can damage speaker systems whose power ratings suggest that the amp can do them no harm.  Melted voice coils and the like. 

[Woodinblack 4,325]

OK, so then for the OP it is a data point. I would not think twice about doing it, you would, so it is up to them what they do.

9 minutes ago, Lfalex v1.1 said:

Definitely this. Its when the power amp stage starts to clip that even relatively low powered amps can damage speaker systems whose power ratings suggest that the amp can do them no harm. 

The TC power amp has the power management to prevent the power stage clipping, which is what all the fuss and anger about their power ratings comes from.

[agedhorse 258]

Have you looked at the comprehensive answers and information given to you over at your same thread at TB???

[jjl5590 15]

Sure have 

[Bill Fitzmaurice 761]

3 hours ago, Woodinblack said:

...the output rating of the RH750 is...less than 300W, so into a 400W speaker you should be able to run it flat out at any frequency for hours on end

The power rating of a speaker is thermal, literally how much power it can take before the voice coil fries. How much it can take before mechanical damage may occur is seldom more than half the thermal rating. Besides, most amps are rated for their output capability at a very low distortion figure. Most are capable of at least twice their rated power at high distortion, albeit not long term. A sufficiently high pulse can fry a voice coil in a fraction of a second.

Quote

The TC power amp has the power management to prevent the power stage clipping, which is what all the fuss and anger about their power ratings comes from.

A watt is the product of voltage x current, period. The TCs have been proven incapable of delivering the requisite voltage at the requisite amperage to come even close to their advertised ratings.

[Woodinblack 4,325]

36 minutes ago, Bill Fitzmaurice said:

.A watt is the product of voltage x current, period. The TCs have been proven incapable of delivering the requisite voltage at the requisite amperage to come even close to their advertised ratings.

Exactly my point

[Sparky Mark 253]

5 hours ago, Woodinblack said:

Exactly my point

I think you are ignoring the first part of Bill's post that clearly states the thermal rating of cabs is no guarantee that you won't damage a speaker with a lower rated amplifier. Even if the RH750 is only capable of 300 watts RMS output it is still more than capable of killing a 400 watt thermal rating cab even without distortion. Max the volume and the low end eq then try some heavy slaps and pulls and see how that ends. The answer to the thread question is still yes; it even says "too loud too low".

Edited November 28, 2020 by Sparky Mark

[Sparky Mark 253]

6 hours ago, agedhorse said:

Have you looked at the comprehensive answers and information given to you over at your same thread at TB???

https://www.talkbass.com/threads/can-i-damage-my-cab-by-playing-too-loud-too-low.1491079/

The answer is still yes here as well. 

Edited November 28, 2020 by Sparky Mark

[Woodinblack 4,325]

37 minutes ago, Sparky Mark said:

I think you are ignoring the first part of Bill's post that clearly states the thermal rating of cabs is no guarantee that you won't damage a speaker with a lower rated amplifier. Even if the RH750 is only capable of 300 watts RMS output it is still more than capable of killing a 400 watt thermal rating cab even without distortion.

Yes, I just checked, turned out the speaker is an 8 ohm, I was thinking it was a 4. So I doubt it can get over 200w.

Sure, you can't guarantee anything, maybe there is a manufacturing defect, or maybe you are going to find its resonant frequency  and leave it running for a few hours. If you are determined to do a thing you can probably do it.

But as I said, it is not something I would worry about at all if it was equipment I had paid for. 

But you pays your money, you takes your choice.

 

[agedhorse 258]

Then why did you bother asking this question if you already knew the answer you wanted to believe? 
 

There’s a lot to learn from the answers and comments that were made my members here and on TB, it appears you have missed the essence of this information.

[Bill Fitzmaurice 761]

49 minutes ago, Woodinblack said:

Yes, I just checked, turned out the speaker is an 8 ohm, I was thinking it was a 4. So I doubt it can get over 200w.

It doesn't matter. I can show you many examples of how a 450w driver can be ripped to shreds with 50w input. Here's one:

It's quite easy to do with a signal an octave lower than the speaker was designed to handle, which is very much what the OP described doing.

[Lfalex v1.1 702]

Yikes.

[jjl5590 15]

8 hours ago, agedhorse said:

Then why did you bother asking this question if you already knew the answer you wanted to believe? 
 

There’s a lot to learn from the answers and comments that were made my members here and on TB, it appears you have missed the essence of this information.

Is this directed at me?

[Woodinblack 4,325]

8 hours ago, Bill Fitzmaurice said:

It doesn't matter. I can show you many examples of how a 450w driver can be ripped to shreds with 50w input. Here's one: 

It's quite easy to do with a signal an octave lower than the speaker was designed to handle, which is very much what the OP described doing.

Agreed it is easier to do with a signal an octave lower than the speaker was designed to handle. Maybe when TC made the RH750 and matching cab they thought that they might be used together?

As I said, all of what you are saying is true for other amps and other speakers, and I have no questions on that. The RH750 has Active power management (that it is often slagged off for) which means it will never produce more than 35V (see attached) without clipping (as it peaks), and it has (according to talk bass where it was tested - I have no other sources) a 2nd order HPF starting at 70Hz at 12dB/Octave.

It is incapable of producing a 'signal an octave lower than the speaker was designed to handle' as literally the speaker was designed to handle the output of the RH750.

Add as a caveat to that, the HPF is only in the power amp, so if you take the output from the DI or the preamp out, and put that through an amp, then yes you really can damage it.

I don't see there is much point adding anything else to this, although seeing as the TC RH amps are very common and most of the time paired with the RH cabs, I am obviously happy to see links to all the 'my amp broke my speaker' threads that must exit.

To the OP, don't put any bass into any speaker, as apparently it is far too risky as none of them can handle it.

 

tc450 stats.pdf