What compressor to buy?

[cadunkle]

I'm in the market for a new compressor. I currently have a single stage 3 HP Husky rated at 10.2 CFM at 90 psi. It's adequate but I could use a little more air for sustained blasting. I'd like a 2 stage and a little more air. I also need to move the compressor to a new location (second floor of shed) and would prefer to do this lift only once so it may be time for a new compressor. I have a 12x24 aftercooler, Norgren filters, and Solberg intake silencer and filter I would move to the new compressor.

I was pretty much set on the HF 60 gal, 2 stage, 5 HP, 15.8 CFM, which is a rebadged BelAire 216V (https://www.harborfreight.com/5-hp-60-gallon-165-psi-two-stage-air-compressor-93274.html). This unit has an inline Italian pump and generally seems to have good reviews. Regular price $800, I've been waiting for it to go on sale for $750 which it does from time to time.

I've recently saw at Lowes they have an 80 gal, 2 stage, 5 HP, 15.8 CFM unit for $900, which is a rebadged Campbell Hausfield HS5180 (https://www.lowes.com/pd/Kobalt-80-Gallon-Electric-Vertical-Air-Compressor/1000528985). This unit has a V twin Chinese pump that I haven't found any info about performance, longevity, etc.

Lowes also has a 60 gal, 2 stage, 3.7 HP, 11 CFM unit (https://www.lowes.com/pd/Kobalt-60-Gallon-Electric-Vertical-Air-Compressor/1000542193). This has the same pump as the 8 gal 5 HP Lowes compressor, just spins it slower with a smaller motor on a smaller tank. Down the road I could change the motor for a 5 HP and spin the pump faster for 15.8 CFM.

Vibration is a consideration as this will be mounted on the second floor rather than on a pad. I'm not sure the merits of inline vs v-twin pumps but I'd imagine v-twin has the potential for better cooling. Whether that matter given my aftercooler I don't know. Chinese pump vs Italian pump also concerns me. Though the IR compressors I saw at Tractor Supply all have Chinese pumps and sell for significantly more than any of these. What do you guys think of these compressors or any others I haven't mentioned? What would you get in my situation?

 

[3rdgendslmech]

I purchased the 2 stage 60 gallon kobalt and love it so far. Takes a while to build up from empty but is pretty quiet compared to a single stage.

 

[Deadsquiggles]

Do you have a Northern Tool near you? IIRC, they sell a 2 stage 80 gal comprsssor for ~$900.

 

[tom-ky]

I have had the Harbor Freight one for about 18 months and happy so far. A friend has had one for several years with no issues.

 

[Marctrees]

I have the HF one w the Italian pump.

IMHO best value out there in that cfm and tank size class.

Be aware - When I bought mine like 5 months ago, HF was disciontinuing that particular one... and substituting their other one.

Unless something has changed.. if you order online you will NOT get the ABAC one.

ONLY by caling numeous HF brick mortar locations will you possibly even find one.

AND.. BEFORE you get in the truck to drive 50 miles to pick it up.. MAKE SURE the store manager lays his eyeballs ON THE UNIT to confirm it is the ABAC.

When I was searching for one some stores said "Yup, computer shows we got it" then they went to look at stock and it was the Chinese one NOT the ABAC.

Marc

 

[Marctrees]

Strange - Looked at HF website - They are only showing the ABAC one, and no longer show the 5 hp 60 gal chinese one.

Hmm.

Odd.

Just make sure.. funny stuff goin on w that item.

Great bang for the Buck if you can get it.

Marc

 

[theoldwizard1]

... I could use a little more air for sustained blasting. I'd like a 2 stage and a little more air.

Forget anything not rated at least 5 HP and at least 15 CFM.

 

[Marctrees]

Very true, unless just doing occasional smaller stuff.

Like maybe a bike frame.

But like to do wheels, naked bare vehicle frame, redo an offset TX style BBQ "Pit"..

True 5 HP is kinda the minimum.

Good enough for home shop.

Gonna get hot though, I hang a good fan over it to help cool when doing like a Jeep frame.

Marc

 

[cadunkle]

Maybe a change in plans, I got a free compressor today from a friend. Supposedly works fine but he left it in his old small shop and got a new larger compressor when he had his new shop built. It's an IR 30T, pump is a model# 234 (234C2). It has a 1 HP electric motor on it, but from what I can figure this pump was used with various motors up to 7.5 HP making 15+ CFM at 1575+ RPM. This compressor appears to be rated at 610 RPM with a 2 HP motor as it came originally. If I run this pump and tank maybe I can change to a 5 HP motor with pulley to spin it faster.

I'm a bit leery about running this old of a tank. I'll get a peek inside and see how bad it looks, maybe have it hydro tested if it looks rough. I'll ask one of the guys at work that said it's cheap to get a tank tested. Old tanks scare me, I don't want a bomb. I'd prefer a horizontal tank for my space so it would be nice if this is serviceable as new horizontal tanks seem to be $1000+.

For the pump it turns by hand and seems to pump air. I can get a rebuild kit with rings, gaskets and valves for around $100. Seems like at least I'd got a good made in USA pump for about $100. Maybe use on this tank, find another tank, or use on my vertical tank that I got new and I know has been drained regularly and taken care of. I could also do a remote tank setup using this pump.

In any event, I'm not sure exactly how I'll proceed at this point. Thoughts?

 

[Citation]

It's not a big compressor but you might consider just adding that as a second pump to what you have right now. Basically if the pump works it's probably good for about 5 CFM as is. I'm not sure about the pressure range but given it's a two stage pump I would assume (and you would have to verify) it could run the same pressure range as your current compressor. So *** a second power line and pressure switch to your current compressor. Have that second line feed into this motor and pump (dump the tank). Now you have the extra flow you need without spending more money. When you aren't blasting just turn it off and use the Husky pump alone.

 

[metlmunchr]

The 234 pump is rated for 3hp max and 1000 rpm max. The later model 2340 pump has the same bores and stroke, but is rated for 5hp. But, if you look at one of the packaged compressors running the 2340 pump and 5hp, its output is only 14 cfm, which is one of the lowest air deliveries you'll find on a 5hp compressor. That's indicative that they're running it to the point where its losing pumping efficiency.

IMO, you'd be ahead to just put a 3hp motor and proper sheave on the 234, and like already mentioned, run it in tandem with your existing compressor.

Also, there's no real point in running a 175psi cutout pressure just because a compressor is capable of building that much pressure. For an application like blasting which uses a lot of air, pumping the tank up to 175 might give you 5 seconds of additional blasting time before the pump kicks on, but once the compressor is running, chances are its gonna be running continuously until you're done blasting. For other uses like air tools, etc where the demand is less, you're just creating extra heat, load, and wear on the pump by running at 175 psi.

Both of the compressors in my shop where I make a living are set to cycle between 115 and 140 psi. In the last 15 years, I've replaced a line on one that cracked due to vibration and a belt on the other one. And, fwiw, the one I use as my primary is a generic 5hp single phase with the Italian pump like the one linked from HF. Got a 10hp as a backup, but its in an area where I work a lot while the 5hp is about 100ft away, so the 5hp gets run most of the time for noise purposes. Its powered up 24/7 and although I don't have any major leaks, between 600 ft of air piping and 24 drops, it still cycles about once per hour even if nothing's going on in the shop. If it was pumping to 175 on every cycle I seriously doubt it would still be going strong at 15 yrs old.

 

[rburke65]

Well the 10 cam, or the 15 cam, or what ever don’t mean a whole lot as there was no psi stated.....unless I missed it.

 

[cadunkle]

The Harbor Freight 60 gal 5 HP 2 stage went on sale $50 off, so for $749.99 out the door I went for it. I'll have to get a filter adapter to change the intake from a tiny plastic box to NPT so I can run the Solberg silencers I have. I think I can get that for about $10. I may add some more components to quiet it down depending on noise level. Beyond that worst case a few bucks more for some fittings and copper tubing to use my aftercooler.

I may keep the 234 pump, rebuild it, and run it slow with the 1 HP motor or something else. The new compressor is going in a separate building which I've run 3/8" ID tubing through existing conduit to the garage. I plan to put a 20 gal tank up high in the garage. If that line is ever inadequate under heavy use I can run the IR pump at a lower cut in pressure. Either that or I'll just sell it if it's not necessary to keep up with worst case use.

 

[Marctrees]

Congrats !!

So you have in your possession a verified ABAC pump unit?

Sticker on pump says "EU" (European Union)

Tough to find or not ?

What state did you pick it up in?

Marc

 

[cadunkle]

I don't know, it says Made in Italy and looks like a T29s. I got it at a Harbor Freight in DE, closest one with no sales tax. Called, they had one in stock, so I went and got it.

I've been traveling a lot for work lately so progress with any projects has been slow. I got back the other day so called a buddy and got it moved to where it'll live. I still need to reinforce the floor, I'm hoping I can keep vibration to a minimum but it'll be nice having more usable floor space. Hopefully I can get that done and wire it up before I have to travel again. I also need to order the intake adapter to run the Solberg setup from my other compressor.

I got some rubber/cork layered pads to put under the feet when I bolt it down. I'm considering cutting some up and putting these between the pump and tank to try to quiet it down some more. It's in the shed away from my main work area but I'm moving my sand blaster to the shed and it'll run more than not while blasting so every bit I can quiet it down helps.

 

[Marctrees]

That specific unit from HF is by far the best bang for the buck in the Market.

It just seems unclear if the are continuing to carry t, or discontinuing.

Next step up pricewise is The SAME unit branded BelAire is ? $200 ? more.

Congrats on your purchase.

Marc

 

[Marctrees]

HITH did you get it up on that shelf ?

That took some thinking.

Marc

 

[cadunkle]

Indeed the same unit from BelAire is about $300 more when I checked. Only difference I can tell is the intake on the BelAire has a flat to NPT adapter and a proper silencer/filter assembly. I could make an adapter but they're $10, or $30 if you want the "kit" with bolts and a gasket. Sure I'd like a larger pump turning slower than the 1400 RPM this turns, but it can't be worse than my 3 HP Husky single stage that has served me well for over a decade and will probably sell for around half the cost of this.

As for how I got it up there, it appeared daunting at first. I removed the pump and motor, brought them up separate. The tank is heavy but I can lift it on the ground myself. After pondering logistics up a ladder for a quickie or time to mount a pulley setup I called a buddy and we had it up and assembled in a few minutes. Easy two man lift walking it up ladders hanging between us from a strap, once high enough tilt it over the edge and stand it up.

Now a question on wiring. Originally I thought it would be too tall and would have to go at the back of the upstairs where there's more headroom. I got a disconnect I was going to run wire through studs down low to the disconnect then a NM whip up to the compressor.
When I saw it will fit directly over the panel I figured disconnect next to the door and whip to that, similar to the picture.
Now I'm not sure I should bother with a disconnect that will only be a couple feet from the breaker and the compressor directly above. I recall reading that a disconnect was only required by code over a certain distance? I'm considering running NM from the panel to a box upstairs beside the compressor and run the whip behind the compressor to the junction box, leaving the breaker as the only disconnect. Is this acceptable? How would you wire this?

 

[Marctrees]

Others will answer your other questions.. but if you use NMB it ideally, least by Code. should be #8 on a 30 breaker, rather than #10.

In real use, #10 is used by many, including myself, but if NMB, Code says #8.

Marc

 

[cadunkle]

I plan to use 6 gauge NM-B from the panel to the disconnect or junction box (leftover from a previous project, and it'll future proof the compressor circuit), then 10 gauge THHN in NM flex conduit for the short run to the pressure switch. The motor itself has 10 gauge cord to the pressure switch. I can go to larger if there is any reason to do so for safety or code compliance, but the motor nameplate only says 22 amps. I do have some 6 gauge THHN and 10 gauge THHN left over from a previous project. I could do 6 gauge all the way to the compressor but I think that's way overkill and would be a pain to terminate.

 

[isb cornbinder]

I have an Ingersoll Rand T30 on an IR 80 gallon tank. For what it is worth, as information only. I like it and this system makes enough air to keep up with my MODULBLAST E series 2448 cabinet.
https://www.modublast.com/e-series-economy-suction-blast-cabinets
An American dollar buys $1.40 Canadian. This is like a big discount.

 

[Marctrees]

"I plan to use 6 gauge NM-B from the panel to the disconnect or junction box (leftover from a previous project, and it'll future proof the compressor circuit), then 10 gauge THHN in NM flex conduit for the short run to the pressure switch. The motor itself has 10 gauge cord to the pressure switch."

What you said sounds great.

A second disconnect at the compressor is not needed if your breaker panel is "within sight"

Your'e doing great.

Marc

 

[Marctrees]

"I plan to use 6 gauge NM-B from the panel to the disconnect or junction box (leftover from a previous project, and it'll future proof the compressor circuit), then 10 gauge THHN in NM flex conduit for the short run to the pressure switch."

Yup, sounds good.

A disconnect by the Comp is not necessary if your panel breaker is "within sight" of the Comp.

Doing good.

Marc

 

[cadunkle]

I finally got back to this today. Wiring I finished before I had to travel for a week. Finished as I said, I used a 35 amp breaker as that's the lowest size that accommodates 6ga wire. My understanding is this is fine for a compressor circuit.

I doubled up each of the 7' 2x6 floor joists, added bracing directly under the compressor between joists. I'll continue bracing on 16" centers. Structural screws across the ledger boards into the walls, which were drywall screws originally. Tank mounted to the floor using 7/8" thick pads that are rubber on each side with a rubbery foam core, and 6" lags with large washers on top.

The compressor makes more noise than I'd like but is not obnoxious a few feet outside the shed. It's serviceable at current noise levels without making me go deaf or annoying the neighbors, but I will try to reduce noise because I'm OCD like that. I'd break the noise down into two types:
One is high pitched intake noise from the factory plastic filter box, it goes away if I hold my hand over the intake momentarily. That should improve significantly once I get the Solberg muffler and filter/muffler housing installed. I can modify the intake as needed to reduce this noise further.
The other is vibration of the floor. I knew this would be a factor. I expect it to be reduced with additional bracing of the floor. I may add a column just outboard of the fridge.
For additional noise reduction I intend to add insulation along with OSB on the interior walls which should dampen noise and make the structure more rigid. Maybe insulation and OSB on the ceiling as well. With open walls and no insulation it's very loud inside from any noise such as hammering or impact drivers, there's not much to dampen it or keep the noise inside.

 

[Marctrees]

Maybe overkill, but I would tie it off to the wall near the top.. not tight, but restrained.

Sounds like you have it screwed to the floor pretty good .. but I would do belt and suspenders w 400 lbs over my head.


Marc

 

[cadunkle]

That thought occurred to me, secondary bracing or support. I doubt it'll go anywhere but I was thinking strapping to the wall, snug with an old tire tube for damping. Your idea could work just as well for that purpose. Maybe a chain or strap to the rafters. It's supposedly around 275 lbs, not ridiculously more than standing up there but all the same it would be a bad trip to the fridge if it came down on me.

 

[Marctrees]

So, now you can do a bit of piping w a 1/2 ball valve and hang a 5 gal bucket for your condensate.

If you do that - LEAVE the lid on the bucket and just punch a 2-3" hole in it.

And maybe baffle that hole w a screwed on Scotch Brite pad.

If you do not have a lid much of the water will be blowing out of the bucket and raining on you.

Or even run a flex hose after the ball valve and drain through wall outdoors ??

You got this far done very well, I'm sure you'll figure it out.

Looks good.

Marc

 

[sberry]

Could have used the more common 40 breaker. Legally a 50.
Btw,, the 175 pumps will produce way more than that. North of 200, not sure exactly but the factory that set them determined this was the correct pressure when they did it. The main reason to get it in the ist place is for his reason, if not a cheaper comp would do.
It's to provide headroom to provide constant air to regulated circuits, to aid in transmission and be able to turn it up to manage loss thru common used hoses and fittings.
Why plumb the drain in a bucket, put a hose thru the wall, blow it outside. Whoops,,, saw that mentioned.

 

[Marctrees]

Re making comp quieter..

In addition to your intake mods.. get some 6" + FB cheap regular insul and do the walls/ roof near around the comp.

If faced, just multi slash w razor knife and put facing to exterior- Bare pink insul side needs to go against the noise source.

Lastly - If you run the pump for extended times, and/or your ambient temp is high, blow a fan up there to circulate around the pump/ motor.

I had an IR 5 hp 80 gal that I did sandblasting with.. a good strong fan really helped.

Marc

 

[tom-ky]

Indeed the same unit from BelAire is about $300 more when I checked. Only difference I can tell is the intake on the BelAire has a flat to NPT adapter and a proper silencer/filter assembly. I could make an adapter but they're $10, or $30 if you want the "kit" with bolts and a gasket. Sure I'd like a larger pump turning slower than the 1400 RPM this turns, but it can't be worse than my 3 HP Husky single stage that has served me well for over a decade and will probably sell for around half the cost of this.

As for how I got it up there, it appeared daunting at first. I removed the pump and motor, brought them up separate. The tank is heavy but I can lift it on the ground myself. After pondering logistics up a ladder for a quickie or time to mount a pulley setup I called a buddy and we had it up and assembled in a few minutes. Easy two man lift walking it up ladders hanging between us from a strap, once high enough tilt it over the edge and stand it up.

Now a question on wiring. Originally I thought it would be too tall and would have to go at the back of the upstairs where there's more headroom. I got a disconnect I was going to run wire through studs down low to the disconnect then a NM whip up to the compressor.
When I saw it will fit directly over the panel I figured disconnect next to the door and whip to that, similar to the picture.
Now I'm not sure I should bother with a disconnect that will only be a couple feet from the breaker and the compressor directly above. I recall reading that a disconnect was only required by code over a certain distance? I'm considering running NM from the panel to a box upstairs beside the compressor and run the whip behind the compressor to the junction box, leaving the breaker as the only disconnect. Is this acceptable? How would you wire this?

Where did you buy the items to change the filter set up? Approximate total cost?

 

[Citation]

I've recently did some work with my compressor to reduce noise. As such I have a low cost air intake suggestion. My compressor is a belt drive 120V CH so not as big as the one here but the logic should hold. It's also the same thinking California Air Tools uses on their intakes.

Basically put a rubber hose of some type after on the intake side of the air filter assembly. I recently had to replace the filter housing on my compressor and the updated OEM part looked something like an old school, on top of the carb air fliter assembly with a single intake off to one side. See the link below for a similar setup.
https://www.walmart.com/ip/Campbell...0056AV-Air-filter-housing-w-element/911040781
The intake tube was about 5/8" OD. I bought about 1' of 5/8" ID tube, slipped it on and dropped 3-4 db of noise (per my phone noise level app). Additionally the quality of the sound was better. Again per my phone app this put my 20 gallon, belt drive CH at about 1-2 db louder than my CAT 5510A low noise compressor. In person I think the CAT sounds less obnoxious and quieter but still, that's not bad.

My take away from this is don't bother with a lot of pipes and elbow joints, just put 2-3' of rubber/flexible hose either before or after the actual filter element. My guess is the flexibility of the rubber hose makes for a good dampener of the pressure pulses in the intake. I'm also going to assume it's good to have the length of the hose at 20x+ the diameter. I have very little on which to make that claim other than the section of hose I used was probably about 20xID in length.

In my case the hose cost $1. The filter was $14 and was needed to replace the original which lost a cover in transit. I might try similar rubber hose experiments with my father's and brother's 80 gallon compressors.

 

[Citation]

This offers a fairly realistic idea just how effective some hose can be

That compressor is very similar to mine but that isn't the same type of air intake. I also used a short section of tube. The CAT compressor does have an intake very much like that one but smaller. It uses what looks like a 1/4" ID tube at about 3-4" long. It would be really easy to overlook just how much that short bit of tube does for reducing the sound levels.

 

[soj]

I doubled up each of the 7' 2x6 floor joists, added bracing directly under the compressor between joists. I'll continue bracing on 16" centers. Structural screws across the ledger boards into the walls, which were drywall screws originally. Tank mounted to the floor using 7/8" thick pads that are rubber on each side with a rubbery foam core, and 6" lags with large washers on top.

If your concern is the strength of the floor, run something from the floor joist up to the roof truss...
jp

 

[cadunkle]

I already ordered another Solberg silenced (glasspack basically) and filter/silencer. I also have a 18" or so long piece of flexible metal hose (corrugated) with 1" NPT ends I'll use as well (intake mounted to wall most likely). I'll see what this does, then try adding my other Solberg glasspack style silencer and see if multiple make any improvement. I also have some 1/2" neoprene/rubber sheet I will try mounting between the pump and tank to see if that isolates vibration any or further reduces noise.

Today I added additional bracing to the floor. This has noticeably reduced vibration of the structure. I also got a 4x4x8 and some hardware to put a column on the center joist right next to the fridge. I expect this to further reduce vibration. Even without a column in place the floor is noticeably more rigid when walking up there.

I picked up some R19 to put under the floor and some R13 to put on the flat wall to the left of the compressor. I'm not sure how I'll insulate the gambrel roof, I understand there are issues with condensation depending how you do this.

I also got a cheap decibel meter. After bracing the floor I measured decibels while standing at ground level. Max DB recorded was 86. I have not seen a DB rating for this compressor but for comparison the Lowes 5HP compressors are rated at 87 DB. Before I change anything I'll also take a measurement standing outside the shed. Lower noise inside will be nice for sure but I want to keep it as quiet as possible outside.

 

[cadunkle]

The Solberg glasspack silencers are relatively expensive at $77. One and the Solberg filter/silencer pictured above dropped it to 84 DB. The intake noise was still noticeable, but quieter and a deeper less annoying tone.

I got a pair of Thrush 24204 glasspacks 2" in/out, 26" body length. These were $17/ea. I also got a Thrush 17712 turbo muffler offset/offset 2" in/out. i figured the glasspacks muffle but are straight through, so adding something with more of a maze would help. In the same line of thinking I changed the straight reducer fitting out of the compressor head to a two 90* fittings, the first being a reducer from 1" to 1/2", the seconds a 1" street 90*. I used a pipe expander to slip the ends of all the mufflers over eachother and weld them together. A space piece of 2" hose from a turbo plumbing project on one end clamped to 1.5" black pipe. Welded 1.5" black pipe to the outlet end and threaded a 1.5" to 1" reducer on and then into the Solberg setup.

I also got some 1/2" neoprene rubber sheet and cut pieces of that to mount the pump on, and figured I may as well use it under the fasteners too. So I made neoprene washers to go under the steel washers, and strips of neoprene to go under the feet of the pump.

I also put a jack post next to the fridge under the compressor, which I will make permanent with a 4x4 post at some point.

The result of all this is a reading on 81 DB. The noise I can hear is 98% mechanical noise from the compressor, 2% vibration of the floor. The intake is virtually silent. If I put my ear close to the Solberg filter it I can hear the pump sucking air. This is as good as it gets for intake noise. The only way to reduce it further with this pump is to spin it slower. The decibel reading is down in the 70s standing under the mazzanine where I'll put my sand blaster and a bench.

For fun I'll try taking the Solberg setup off and see how much difference that actually makes after the automotive stuff. If I was to do it again I wouldn't bother with the Solberg glasspack, Thrush are much cheaper for much more muffler and I have the room for it.

To further address vibration I'll insulate the floor under the compressor and put OSB on the bottom. I expect this to dampen noise and make it more rigid. Additional insulation in the structure should absorb more noise too.

 

[cadunkle]

For an experiment to quiet this down more I picked up a 3" pulley to replace the factory 5 3/8"" pulley. This will reduce pump RPM from 1388 to 775. The pump is rated for 700-1400 RPM. I'm curious how much this RPM reduction will reduce noise as well as vibration being mounted high. I have the pulley installed but need a shorter belt as I'm just out of adjustment with the factory 55" belt. I guess I'll find out how it performs later this week.

Interestingly, there is a larger version of this pump (T39, instead of T29) that looks virtually identical but scaled up to move more air. It is rated for the same 700-1400 RPM range, 5 HP at lower RPM and 7.5 HP at higher RPM (as opposed to the T29 rated for 3HP at 1000 RPM and 5 HP at 1400 RPM). I'd imagine noise and vibration at 775 RPM would be similar between the two pumps.

In any event, I don't do much blasting lately so I think it'll be fine for most of my use, if there's appreciable noise reduction. Sitting unused I have an IR Type 30 324c2 pump set up to turn 575 RPM, probably fairly quiet. It was given to me and I've never run it. This would probably work plumbed in and kicking on at a lower pressure. I have a 20 gallon tank in the attic of my garage, so 80 gallons total storage. I'm considering putting the IR pump and motor up in the attic with some vibration isolation if it runs fairly smooth.

 

[Hobby_Man22]

i'd buy a quincy 80 gallon

 

[like2wheel]

I have a Quincy QT-5 that's 3 phase. I wired in a VFD to get it to run on single phase & I can adjust the HZ with a dial to change the rpm. I set the limits from 30 to 70hz to keep the pump within its rated rpm. Goes from a slow thunka-thunka-thunka to a full roar when I need extra volume.
I know you already have your compressor, but its something to think about if you occasionally need the volume but want it quiet most of the time. Or vice versa.

 

[Citation]

If noise is an issue look at some type of intake muffler. I cut about 8 db of my compressor going from an intake with basically no noise suppressor to a CH, OEM "automotive style" filter housing + 14" off rubber hose. Huge improvement for under $20.

 

[Burl]

Being in the market for a compressor, as my 60 year old Kellogg just gave up the ghost, I ventured to a semi-local HF and found the exact one as you bought, only at a $849 "clearance" price.