Quiet compressors

[Fallon]

Slow oil lubricated belt drive compressors are where it's at. I upgraded to a real 5hp 80 gallon Quincy a year or 2 ago. It's a lot quieter than my previous ones. The 60 gal "5hp" oil lined Kobalt wasnt bad, but not super great. Way better than all the oil free ones.

I hear the new scroll compressors are wicked quiet compared to a piston pump. The rotary compressors are really nice as well but way more than my high end Quincy. You need to use rotarys a lot so they heat up & stay hot, or they don't have issues. They dont work well for occasional usage.

 

[Meghan]

I have this one California Air Tools 5.5 Gal. 1.0 HP Ultra Quiet and Oil-Free Air Compressor and I'm glad about it. What about the cons? I didn't find cons yet. I use it for 2 years :thumbsup:

 

[strantor]

I keep seeing recommendations here for the bigger belt-drive units and I don't see where y'all are coming from. I've worked a few places that had those and they're still pretty loud from what I remember. The last place I worked had a Quincy compressor, low speed, big wheel on the compressor, it was so loud we moved it out of the shop and build a lean-to over it, and afterwards it would shake the shop wall when it was running.

Is there more than one kind of belt-drive low speed compressor, with some being more quiet than others? What should I be looking for? Because when I see the belt drive units all I see is something that's probably almost as loud as a 26gal craftsman oil free compressor.

 

[Jchonline]

I have this Husky from HD. It is considerably quieter than my 6 gal Ryobi pancake. I have to put on ear pro for the Ryobi. Not so for the Husky. I do think there are quieter out there, but this was a pretty good buy.

 

[orezok]

I have an 80 gal cheap compressor in my shop. It has always been very loud. I did some investigating and determined that most of the sound comes from the air intake. The compressor is located on an outside wall so I connected a 1” thick wall hose to the intake, ran it through the wall and put a sound deadening air filter outside under a weather cap. SO MUCH quieter now.

 

[rScotty]

I keep seeing recommendations here for the bigger belt-drive units and I don't see where y'all are coming from. I've worked a few places that had those and they're still pretty loud from what I remember. The last place I worked had a Quincy compressor, low speed, big wheel on the compressor, it was so loud we moved it out of the shop and build a lean-to over it, and afterwards it would shake the shop wall when it was running.

Is there more than one kind of belt-drive low speed compressor, with some being more quiet than others? What should I be looking for? Because when I see the belt drive units all I see is something that's probably almost as loud as a 26gal craftsman oil free compressor.

There was a time when "service stations" were a common landmark in the US. The service stations disappeared, but the tools remained. And for awhile used compressors were common and used tools shops were found in every town. Neither seem to exist much anymore.

We tried several compressors at my repair shop because rarely a week went by when someone didn't show up in a pickup truck with a used compressor for sale. Anyway, I agree & never thought that the Quincys were nearly as quiet as the older examples of that style compressor. Some of those uprights were like the Quincys in that they did look like the old quiet ones, but they were louder. Could have been something wrong with that particular Quincy, too.

There's going to be exceptions, but at our shop the mechanics like to listen to music while they work. And to reduce the compressor noise at our shop we did the traditional things: old style splash oil cast iron long stroke type compressor head run via a belt & large pulley. Kept it outside and piped the air inside.

The problem is that those quieter types is that they are also slower so they need a larger storage tank or more cylinders...and both get expensive. A decent used shop size compressor costs.
rScotty

 

[strantor]

What I'm thinking is, those little 1HP/6gal "silent" import compressors may not put out enough air for a shop, may not be capable of continuous duty, may not last as long as a good quality one, etc., but...

At <$150 each, I could buy 5 of them, plumb them together along with my 26 gal craftsman acting as a storage tank, and I'd have:
5HP
56gal
15.5CFM @ 90PSI
125 PSI max
51db (whisper quiet)
... all For $750.
I could connect an analog pressure sensor to a little programmable control board like an Arduino, which would track the run time of each compressor and when the pressure drops below, say 120PSI, it could switch on a single compressor, whoever has the lowest hours. And if it drops below 115PSI, it can switch on a 2nd compressor, the next-lowest-hours compressor, and so on in cascading fashion until all 5 compressors are running in response to a large air demand. This way none of the compressors has to run continuously and as long as air demand is minimal (which is usually), the run time will be divided among 5 compressors, theoretically extending their lifespan by up to 5X. There is the added benefits of having FIVE levels of redundant backup, being able to easily detach a part of your air system and take it on the road, and if a compressor fails you just replace it for $150 and leave the tank connected to your system, so if ever you do experience a failure it's not a total loss; your volume grows with each failure.

Compare that to a quincy such as this:
$1,399
5HP
60Gal
15.4CFM @ 90 PSI
175PSI max
75db (super loud)
Single point failure if the compressor goes out

The only area I see the Quincy winning in, is max PSI, and I never use more than 100 PSI, so I don't see the justification in paying the extra $650.
(oh yeah, and 4 gal more storage)

 

[ultrarunner]

I like outside the box thinking!

 

[thekkfan]

I bought this Craftsman because it said it is 40% quieter. I measured it today with a decibel meter on my phone at 75db & 70db at 10' & 25' away with the overhead doors closed.
View attachment 575826

The odd thing is, this Quincy is 78db &76 db at 10' & 25' away...... I wonder, 40% quieter than what?:confused3:
View attachment 575827

I can vouch for that exact model craftsman professional. My dad has one and wish I could swap with my red upright. It's half the noise of mine.

 

[downsizingnow48]

Five separate 60 db sound sources would be 67 db additive. There are online calculators. Still less than the smaller IR and Quincy belt drives which seem to be about 75-80 db.