ETS EC noise levels?

[live4ever]

I don't NEED a new finish sander, but one of the parts of sanding I'd like to make more pleasurable (if that's possible) is noise.  I have several Festool finish sanders (ETS 150, DTS400, Pro5) and they all do a great job, but if I can reduce the noise output during sanding, I'd really like to.

How do the ETS EC sanders stack up in this regard?  I'm taking a hard look at the Mirka Deros.

 

[Holmz]

I have the DEROS, and it is nice.
I pawed a ETS/EC and it seemed so similar I had to scratch to see if it had a yellow belly.

Doing a lot of sanding one still may want some earplugs or buds, but I am a bit over protective of the ears.

An other quiet one is the uva115e, but it is 1/2-sheet. Both of those and the dx93 seem similar, but opi could find the meter and see/hear.

 

[antss]

One should be wearing ear protection when using any type of tool with a universal motor, no matter how "quiet" it is.

 

[live4ever]

I have the DEROS, and it is nice.
I pawed a ETS/EC and it seemed so similar I had to scratch to see if it had a yellow belly.

Doing a lot of sanding one still may want some earplugs or buds, but I am a bit over protective of the ears.

An other quiet one is the uva115e, but it is 1/2-sheet. Both of those and the dx93 seem similar, but opi could find the meter and see/hear.

Interesting.  You'd say then that they have similar noise levels?  I like the pad switching abilities of the Deros, but don't want to invest in more sandpaper (already have 5" and 6" granat). 

One should be wearing ear protection when using any type of tool with a universal motor, no matter how "quiet" it is.

Completely agree.  However, since sanding tends to emit noise for longer durations than cutting operations, I'm concerned about the other residents of my home (aka Boss and lil' boss) and my cranky neighbors.  [tongue]

 

[Holmz]

I have the DEROS, and it is nice.
I pawed a ETS/EC and it seemed so similar I had to scratch to see if it had a yellow belly.

Doing a lot of sanding one still may want some earplugs or buds, but I am a bit over protective of the ears.

An other quiet one is the uva115e, but it is 1/2-sheet. Both of those and the dx93 seem similar, but opi could find the meter and see/hear.

Interesting.  You'd say then that they have similar noise levels?  I like the pad switching abilities of the Deros, but don't want to invest in more sandpaper (already have 5" and 6" granat). 

One should be wearing ear protection when using any type of tool with a universal motor, no matter how "quiet" it is.

Completely agree.  However, since sanding tends to emit noise for longer durations than cutting operations, I'm concerned about the other residents of my home (aka Boss and lil' boss) and my cranky neighbors.  [tongue]

I would say that the levels are similar, but any sceptic worth his salt would ask for proof.
In the same way Mirka screens can be used in a Festool, I would think that FT papers can be used on a Mirka (I guess I need to check the holes line up...)

Google search yielded:

Deros:
Sound Level 71 dB(A)
Stroke 5-mm
/min: 4000-10000
Power: 350W

ETS/EC: 72 dB(A)
Stroke: (3 or 5-mm)
/min: 6000-10000
Power: 400W

uva115e:
Vibration: 1.9 m/s^2
Stroke: 2.6-mm
/min: 4000-22000
Power: 450W

Naturally the sound can be high if the wood being sanded is beating on the table with no rubber below it... Particularly at low rpm.

My impression is that the UAV is much quieter in the air than the random-orbitals, but that might be due to wind noise in the ROs. On the wood the uva is only quieter when the rpm is higher enough to not have bouncing type of vibration... Maybe 10k rpm or higher.

By the time one adds a vacuum, then as [member=727]antss[/member] mentions... Use protection.

If it was not so stinking hot today I would break out the sound meter...

 

[live4ever]

Thanks Holmz.  You are clearly a better Googler than I - I couldn't find a noise level rating for the ETS EC. 

If I decide it's worth it to get a new sander I'll probably try the ETS-EC.  If it's not vast enough of an improvement, it will go back.  I think overall the Deros is a slightly better/more attractive sander, but it's also significantly more expensive and there have been some rumblings of lemons.  I trust Festool to take care of me much more than I do Mirka.

I had read somewhere that the Deros can take FT paper, but perhaps not as ideal as using Mirka abranet or autonet.

 

[Huxleywood]

One should be wearing ear protection when using any type of tool with a universal motor, no matter how "quiet" it is.

While there one can always take a conservative approach there is no need to wear hearing protection while using a Deros or ETS EC while sanding, unless you like the look.  While I haven't tested my ETS EC the loudest I was able to record (on a high quality SPL meter, not an app) with my Deros 81dB at 30".  This is well below the NIOSH and OSHA PEL for 8 hour days for continuous noise SPL.  It just isn't load enough to do any permanent hearing damage and the spectrum is rather ear friendly as well. 

 

[Huxleywood]

This got me curious so I ran out to the shop ith my second best SPL meter (much more portable than my best mic and laptop) and tried several sanders.

These numbers are max at 30" and obviously against a very reflective surface.

Deros 650  79 dB
ETS EC 150/3  78dB
Rotex RO90 geared 84dB RO 83dB
Rotex RO150 geared 86dB RO 84dB
Pro 5 80dB

These numbers are not based on any standard convention so can only be compared to each other. 

 

[live4ever]

This got me curious so I ran out to the shop ith my second best SPL meter (much more portable than my best mic and laptop) and tried several sanders.

These numbers are max at 30" and obviously against a very reflective surface.

Deros 650  79 dB
ETS EC 150/3  78dB
Rotex RO90 geared 84dB RO 83dB
Rotex RO150 geared 86dB RO 84dB
Pro 5 80dB

These numbers are not based on any standard convention so can only be compared to each other.

Vewwy intewesting, thanks for doing that.  I assume this is while sanding, correct?  My guess would be any major differences in motor noise get wiped out once you start actually sanding, and maybe that's why your numbers are pretty close together.  These seem to indicate that there wouldn't be much gained in terms of sound reduction between my Pro5 and a new ETS EC 125.

 

[Huxleywood]

This got me curious so I ran out to the shop ith my second best SPL meter (much more portable than my best mic and laptop) and tried several sanders.

These numbers are max at 30" and obviously against a very reflective surface.

Deros 650  79 dB
ETS EC 150/3  78dB
Rotex RO90 geared 84dB RO 83dB
Rotex RO150 geared 86dB RO 84dB
Pro 5 80dB

These numbers are not based on any standard convention so can only be compared to each other.

Vewwy intewesting, thanks for doing that.  I assume this is while sanding, correct?  My guess would be any major differences in motor noise get wiped out once you start actually sanding, and maybe that's why your numbers are pretty close together.  These seem to indicate that there wouldn't be much gained in terms of sound reduction between my Pro5 and a new ETS EC 125.

As an aside, since you plan to live 4 ever you may need to be far more protective of your hearing than us mere mortals.  [big grin]

Yes, these numbers were sanding with the same grit and basically just the weight of the sander I didn't try to vary the pressure since I didn't want to be out there all night and I wasn't using a vac to avoid skewing the results.

Now the interesting thing I noticed was the numbers were similar just lower with each running in free air, I didn't record the numbers but probably should have.  What I am saying the the Deros and ETS EC were only a dB or two quieter than the Pro 5 in free air as well.  What I did notice is quite a different frequency spectra for each sander and both the Deros and ETS EC SOUNDED quieter than their actual SPL would suggest.  Both the Deros and the ETC EC's spectra was weighted at a significantly lower frequency than the Pro 5, maybe an octave for the Deros and 1 1/3rd to 1 1/2 octaves lower for the ETS EC.  I would suggest that even if all of these had the same SPL the ETS EC would be the least fatiguing over a long period of exposure.  Now, note my ETS EC is a 3mm stroke, not having a 5mm ETS I don't know if the SPL is higher or not. 

While I would have guessed they are very similar, which they are, IMO and with my rudimentary testing I would say the ETS EC is the "leader in noise".  I still prefer the Deros as a sander and the noise is quite palatable if noise was the number one concern (or a very important one) the ETS EC has an advantage. 

 

[Holmz]

Thanks Holmz.  You are clearly a better Googler than I - I couldn't find a noise level rating for the ETS EC. 

If I decide it's worth it to get a new sander I'll probably try the ETS-EC.  If it's not vast enough of an improvement, it will go back.  I think overall the Deros is a slightly better/more attractive sander, but it's also significantly more expensive and there have been some rumblings of lemons.  I trust Festool to take care of me much more than I do Mirka.

I had read somewhere that the Deros can take FT paper, but perhaps not as ideal as using Mirka abranet or autonet.

I would do the opposite...
Namely try try the screens on a ETS/EC as the screen's holes always line up.
Maybe in the courser grits the FT paper is better, but the 120+ with the screens work for everything except for bumping up against edges.

...
These numbers are not based on any standard convention so can only be compared to each other.

The standard is a measurement at 1M, so if you factor the dB down by 20* LOG10 (30"/39.37")... then it should be equal to a 1M measurement. (However that only accounts for 2.5dB.)

A 5-Mmm stroke maybe noisier than a 3-mm stroke... And I believe that the specs were for a sander in air.
I do not sand air often, and I think that the sanders make noise that is inversely proportional to the grit size.

Basically the DEROS and ETS/EC are both outstanding.
And either is less noise than the RO by 5-6dB, which is only headed towards outstanding in geared mode (IMO).

 

[Huxleywood]

...
These numbers are not based on any standard convention so can only be compared to each other.

The standard is a measurement at 1M, so if you factor the dB down by 20* LOG10 (30"/39.37")... then it should be equal to a 1M measurement. (However that only accounts for 2.5dB.)

A 5-Mmm stroke maybe noisier than a 3-mm stroke... And I believe that the specs were for a sander in air.
I do not sand air often, and I think that the sanders make noise that is inversely proportional to the grit size.

Basically the DEROS and ETS/EC are both outstanding.
And either is less noise than the RO by 5-6dB, which is only headed towards outstanding in geared mode (IMO).

Distance is only a small portion of a SPL measuring convention.  Certainly, I could have done the measurements at any distance but 30" was convenient and closer to the ear to hand distance when actually sanding.  The thing is the conversion you use is only applicable in free field which my testing conditions were not even close to.  My point was my numbers are ONLY useful to compare to MY numbers.  To compare them to any other tests would require an incredible amount of data and keep a super computer happy for quite a while.  Not to mention the mic capsule I was using doesn't have a recent traceable calibration.

My point is simple one can not accurately compare my numbers to any other numbers out there, they are simply only useful for comparison to my other numbers and I feel my numbers are repeatable (by me in my environment) to around 1dB but the way I tested and reported would be laughed out of a speaker building forum for example. 

Also, since the Deros, ETC EC and Pro 5 were all fairly close* in SPL the frequencies that make up the sound have the most direct influence on fatigue (all numbers being under any issues of permanent hearing loss).  While I was fully aware each sander had a different "voice" it actually surprised me how much I "favored" the ETS EC to the Deros and especially the Pro 5, I have heard them plenty of times, just never LISTENED to them back to back with a critical ear. 

Mainly I don't want someone to use my numbers and compare them to a sander I didn't test and draw a conclusion, the likelihood that conclusion would be accurate is very slim and it would be blind luck if it were. 

* while 2 dB difference is actually very significant in terms of acoustic energy our ear/brain processing of sound is not remotely linear, when comparing something like machine noise anything less than 3dB is probably to be considered insignificant in terms of perception but not in hearing loss danger if those numbers straddle a threshold.  Again IMO the frequency was more important between the Pro 5, Deros and the ETS EC. 

 

[AlexThePalex]

While there one can always take a conservative approach there is no need to wear hearing protection while using a Deros or ETS EC while sanding, unless you like the look. 

Odd advice, those power tools are very noisy and certainly not healthy to listen at. As soon as I turn on a power tool - any power tool - all my internal alarms go off telling me it's definitely outside my hearing's safety limits.

 

[Holmz]

[member=62712]Huxleywood[/member] , I would be less likely to comment if you arms were >1m long... But I could still run
So I fully comprehend the 30" distance approach.

I am pretty sure that your sound meter is dB(A) or dB(B). Those numbers are so close to specs that they seems like you are about on the money.
I suppose a test at 1M with the sander not sanding anything but air would tell for sure (??).

Naturally your caveats are a wise risk management approach, but it seems to me that you are scientifically "nailing it". (Sort of late to back peddle when you are already across the line.)

 

[Huxleywood]

I am pretty sure that your sound meter is dB(A) or dB(B). Those numbers are so close to specs that they seems like you are about on the money.

The portable is A or C weighted (you almost never see B weighting used) and I was using an A weighting filter which as you probably know provides a better representation of what humans perceive as loudness at a given frequency.  C weighting would probably have shown a 3-6 dB increase in SPL across the sanders and likely the ETC EC would have shown a larger increase than the Deros based on what my ear says the frequency spectrum is.  BTW OSHA PELs use time weighted average A weighted slow response and 90dB is permissible for 8 hours a day which all the sanders I tested would be acceptable for.

I can't help the caveats my day job encourages the use of a simple statement then a tome filled with every conceivable caveat. 

 

[Huxleywood]

While there one can always take a conservative approach there is no need to wear hearing protection while using a Deros or ETS EC while sanding, unless you like the look. 

Odd advice, those power tools are very noisy and certainly not healthy to listen at. As soon as I turn on a power tool - any power tool - all my internal alarms go off telling me it's definitely outside my hearing's safety limits.

Not odd at all, it is in keeping with standard industry PELs.  I actually measured the noise from the sanders.  Your internal alarm bells are likely reacting to the "quality" of the sound vs the SPL at least with these sanders.  80dB is just not loud enough to cause long term hearing damage, this is based on a well understood scientific field not just a knee jerk reaction.  For comparison 80dB is about the SPL of a noisy restaurant or standing at the intersection of a noisy road.  Just as a comparison a OF 1400 is 89dB tested in the same manner and since the dB scale is a log scale that equates to 8 times the acoustic energy. 

 

[AlexThePalex]

While there one can always take a conservative approach there is no need to wear hearing protection while using a Deros or ETS EC while sanding, unless you like the look. 

Odd advice, those power tools are very noisy and certainly not healthy to listen at. As soon as I turn on a power tool - any power tool - all my internal alarms go off telling me it's definitely outside my hearing's safety limits.

Not odd at all, it is in keeping with standard industry PELs.  I actually measured the noise from the sanders.  Your internal alarm bells are likely reacting to the "quality" of the sound vs the SPL at least with these sanders.  80dB is just not loud enough to cause long term hearing damage, this is based on a well understood scientific field not just a knee jerk reaction.  For comparison 80dB is about the SPL of a noisy restaurant or standing at the intersection of a noisy road.  Just as a comparison a OF 1400 is 89dB tested in the same manner and since the dB scale is a log scale that equates to 8 times the acoustic energy.

It is simply ridiculous to say these sanders can't damage your hearing. But be my guest, go deaf, please, just don't advice it to other people.

 

[bobfog]

I guess it depends on how you use it. I'd say it's quiet enough not to use hearing protection for short intermittent use. But if you're using it on a regular basis for hours a day, I'd be using hearing protection.

 

[Huxleywood]

It is simply ridiculous to say these sanders can't damage your hearing. But be my guest, go deaf, please, just don't advice it to other people.

First, everyone is free to do as they like, it is their body.

Second, share some research to support you claim.  I have objectively tested the sanders, please share your documentation.  I have also provided the industry PELs for 8 hour days and most of the sanders are well below the industry PELs for hearing protection.  Now I understand this can all be confusing for someone that doesn't understand the science of sound and appreciates the logarithmic way the decibel scale works. 

Third, the numbers I produced are only from the sanders and it is certainly possible that shop ambient noise is high enough to cross industry standards for hearing protection.  If one can't test and doesn't understand how to test then it is prudent to err on the side of caution.

Finally, please share your documentation of why you are convinced using the ROS I tested can damage hearing when used in a normal manner ie not holding it against your ears.

To bobfog exposure time is EXTREMELY important that is why OSHA and NIOSH have guidelines for time vs SPL exposure.  If you go see a action movie at a theater that is calibrated to Dolby standards you WILL have transients that reach 105db but you won't walk out with any permanent impairment to your hearing.  If anyone thinks the OSHA or NIOSH standards are too lax or they have no way to test and quantify their environmental sound then ear protection makes sense.

 

[JakobProgsch]

Independently of the actual safety aspect I wear hearing protection against the unpleasantness of the sound alone. By themselves 80db shouldn't be super bad. The reference level of a movie theater is 85 db average and 105 db peak. 80 db also roughly conversation volume or the noise level inside a passenger airplane. Constant droning sounds like motors are probably worse than the more intermittent nature of speech. On the other hand, why even bother thinking about when to protect your ears or not. Just put on the protectors when you enter the workshop and take them off when you leave. And if the protectors cause you discomfort get some nicer ones. If you fill up your workshop with festool products you can probably afford some nice hearing protection