Artist Unknown Quantum QT600 Quantum Dimmable Ballast, 600W

I did a lot of research prior to purchasing and I'm really happy I went with a Quantum. I've been running this ballast 12 hours a day for the past 2 months and it's been excellent. It makes very little noise, and produces very little heat. There is a small fan in the ballast for cooling but you can barely hear it. It's an excellent product, and the dimming feature is great for seedlings. I switched from an old Coil and core ballast, and I'd never go back especially now that these have become so affordable. I run an Ushio 600w HPS in it and it runs like a dream.

I bought two of these same 600w ballast and the 1st ballast put out about 60% less light than the 2nd 600w ballast I bought (my personal 4oow ballast puts out more light than the 1st 600w dysfunctional ballast). Nor was this same dysfunctional ballast ceiled in the packaging like the 2nd ballast was and it also had a small cut to the extension cord as well.I believe it's a hit and miss when you buy certain things off of Amazon. A lot of time one gets returned items from others and those items can be dysfunctional and resold (such as what I believe happened to me).Also, and most of all - You get what you pay for! These are not the best of ballasts, but they do work (at least I hope). If you want to grow really good stuff with durable products than I suggest, spend the extra money and go to a local grow shop and buy all your need's there!The 2nd ballast I bought Ive only had for one day so far, and it seems to work fine. Yet time will only tell how this ballast is to workout(?).

Works great and I have one of these that's 4 years old (the older model) and its still going strong. With the built in fan, cooling fins, dimming, and high power factor (efficiency) there is really no reason to try and cheap out on the ballast at this price. These never get too hot and seem to make the bulbs last a while as well.

I purchased this awhile ago. The only reason I gave it 4 stars is because of the noise factor. It's been an excellent ballast and I would purchase another if fan noise were not an issue. It doesn't have the electronic buzz, just fan noise. Granted, the ballast is not HOT by any means. The dimmable feature is awesome for working my veggies up to full power without changing ballasts or lightbulbs! Basically what I'm saying is, if fan noise is not an issue, this is a great ballast.

First ballast did not work, ordered replacement ballast. That did not work. Returning both and going to a different manufacturer. Yes the bulb was checked and it works on a different ballast

I absolutely love this ballast, its the best one I have ever owned. The dimmable capability is essential for lowering temps in the tent and dialing in on the right settings for your environment. It has high quality construction, has a fan that keeps it cool, and its smaller than any ballast I have seen before. It is a bit loud, but my exhaust fans are much louder than the ballast, so I dont notice any extra noise. All in all, I recommend this ballast. IMO it tops the Lumateks, as Ive heard about some compatibility issues with the Hortilux bulbs (although Hortilux makes "e-ballast friendly" bulbs now too). This Quantum ballast boots every bulb I throw at it with no issues whatsoever.

This ballast is nice and small and quiet. I also have a lumitek ballast and this one is way smaller and lighter. It looks very profesional and made well. good product even though it looks cheap in the picture.

It tripped my breaker and blew my bulb and wouldn't turn back on after 12 hours of use. Put the magnetic ballast back and it runs like a champ. Returned the Quantum and bought an Apollo, been running straight for 48 hours so far alongside the metallic ballast.