Pro-Ject Accu Box S2 Battery Power Supply - Black

I wanted to write a review for this since there isn't a lot of good information out there. First off, the ProJect documentation is extremely simple/minimalist and contains some translation ambiguities particularly in the "Charging" subsection within the Output section. Here is an excerpt from the manual to show you what I mean: ----------- "Charging" - is illuminated when batteries are charged. - is blinking when battery status is low (20%) - charging is not in progress. If the charging is not started manualy by disabling the output sockets it will start charging automatically when battery status is below 10% ----------- Here is how it should read, based on my usage of the product: +++++ "Charging" - is illuminated when batteries are currently being charged. - is blinking when battery status is low (20%) - charging is not in progress. If the charging is not started manually by disabling the output sockets it will start charging automatically when battery status is below 10% +++++ That's a small change, but is much more clear. The second bullet point also sort of implies that once your battery is down to 10%, the device will disable the outputs and begin charging. This was the main thing I was curious about prior to purchasing. However, the device does not disable the outputs at 10% charge. You can still play records (or whatever) uninterrupted while the batteries charge. They do not mention how long the battery life is, and I expect thats' because this can power all sorts of products with varying results. I'm using this to power my ProJect DS2 TubeBox. I get the 20% warning/flashing after around 4 hours of playback. After another hour or so, the Charging light is solid and it will charge on it's own (even while in use) up to 100%. If you disable the outputs when the batteries are less than 100%, it will begin to recharge. Even in that state, you can re-enable the outputs and keep on playing. I'm using this to power the aforementioned ProJect DS2 TubeBox, which is getting signal from my MoFi UltraDeck, going to a Marantz power amp. I have to say, all of the sonic qualities that Project promises is 100% real. "Using Accu Box S2 on any of our recommended products, results in a more homogeneous and spacious sound with better separation and imaging. The sound will come across as more cleaned up overall, giving you a relaxed listening experience with mind numbing sonics." A big plus for me is the removal of the AC line noise from dimmer switches (and other things) in my house, which is now completely gone after integrating the AccuBox S2. This is a fantastic product and I would recommend to anyone that already has some quality gear!

I bought this to hook up with a Tube Box S2 and the Head box, thinking that if it is plugged into the wall the entire time then it will play for hours, I didn't realize it is just a battery. Even plugged into the outlet it won't go more than 2 hours before dying out and needing to recharge. So the time listening is limited especially if you are trying to power more than 1 device. The plug that goes into the outlet is poor quality as well and I am looking for a replacement. I haven't been able to find better 18V Pro-Ject power supplies for this thing, so looks like I'll have to go third party for that.

As most are aware there aren’t many reviews (particularly English reviews) of this product. I have several Pro-ject devices and the first thing you should know is the power sources for these are complete rubbish. Countdown to replacement. The connecting cable will also need to be replaced(2.5 to 2.5 included). I recommend third party. The devices themselves are of exemplary build quality. The review above proved very helpful. The directions will not. It’s unlikely you will be able to connect this to more than one device (that is the job of Power Box DS $799). It does it’s job as advertised, albeit in a very subtle way. I honestly think it should cost about half of what it does, however, they have few competitors at 18v.

As I reported below, I found the Accu Box S2 a worthwhile enhancement to my project tube box DS2, but after 2 years it failed and was replace under generous warranty in December 2025. Now, only 14 months later, the batter pack has failed again. I have always been wary of the design of the unit which relies on a rechargeable lithium battery pack because of longevity concerns. This unit is clearly overpriced at £279 (about $ 375) which amounts to nearly half the price of the units is is designed to support. Add to this its unreliable design concept and you have to decide if it is worth the expense and trouble. I have actually purchased it again, for the 3rd time in 5 years, because it is cheaper than buying a better tube based phono preamp. Still, I am officially unhappy. P.S. Below is my original review from April 2022. I did have a problem with the lithium battery pack failing after 2 1/2 years but the UK distributor, Henley Audio was contacted and replaced it under warranty. Excellent service support from Henley reinforces my original 5 star rating. I had to replace my old Sonic Frontiers Phono Preamp and just did not want to spend a fortune. Still, as I have a VPI turntable with Koetsu cartridge, I needed something good. I auditioned several options at or below the $1000 mark and did hear some nice performers, e.g. Vertere. But I have always preferred tubes with my analog playback and the preamp needed to pair with my integrated PrimaLuna Evo300. When I heard the TubeBox DS2 side by side with the more expensive solid state units I was blown away. No comparison! So I bought it and it has performed beautifully. No complaints EXCEPT is has a dinky off the shelf 18v dc power supply. ENTER the Accubox S2. Compared with the cheap power supply, there is a noticeable improvement in the sound. Better soundstage, more inner detail. It is not overwhelming, but it is there. And once you hear improvement in your system, well, it is hard to resistance scratching that itch. But, two complaints. First, the price is just too high for what it is. Should be under $200. I felt taken advantage of. Second, it is an oddly conceived design and is actually a rechargeable battery pack. There is a red-light indicator that shows when it is charging, and when it is nearly exhausted, but it continues playing without obvious change in performance Still, it bothers me that the full charge (green light ) goes out rather quickly and it always seems to be charging. Not sure what the longevity of the battery will be. Otherwise, I would not say this is an indispensable accessory to your TubeBox, but does enhance the sound if you don't mind paying for the privilege.

The sound stage of my PreBox S2 was vastly improved. I am pleasantly surprised by the result!

Wer sagt das man um gut Platten zu hören eine Sau teure Anlage, einen superteuren Plattenspieler plus Tonabnehmersystem braucht? Einfacher Plattenspieler + gutes System + Pro-Ject Phono- und Accu Box reicht auch. Meine Kette: Denon AVRX 4200 -1500€ Teufel Definion 3 -1200€ Plattenspieler Onkyo CP1050 -500€ Tonabnehmer: AT VM750 SH -372€ Tonabnehmer: Ortofon Concorde Anniversary 40 Moving Magnet -290€ Pro Ject Phono Box 2 Ultra -250€ Pro Ject Accu Box -247€ Die Accu Box habe ich mir als letztes zugelegt. Bring ins ganze Geschehen ruhe, Durchsichtigkeit und mehr Dynamic. War vor der Accu Box schon gut, jetzt noch ein Klang Schippchen obendrauf. Gehört: Yuko Mabuchi -Trio Vol1 Molly Tuttle- When You’re Ready Mary Chapin Carpenter- Sometimes Just the Sky Loreena McKennitt- Lost Souls

After reading reviews I added to my system which consists of : Stream Box s2 ultra pre box s2 digital stream box s2. flac files stored on hdd really pleased with improved sound quality. Stereo seperation more defined I've never heard my 16/44 files in such detail

Alles gut und schnell abgelaufen.