XDIMAX GREX-7.4 Grex Video Stabilizer Review

I have a simple requirement to make some backups of retail vhs tapes to a digital format. You may ask why not just buy the new hd remastered version? Well, that is where it starts to get complicated. Not everything has been released in another format. Those that are released may not be the exact same cut of the film.

Macrovision is of course the copy protection that was introduced in the 1980s to thwart dubbing retail tapes from deck to deck. This is where the Grex comes in. I simply wanted to remove the Macrovision and capture the video through my capture device (an ATI All In Wonder card). I have used this same setup to capture non-protected content with no issues at all over the years. My older device, a Sima Color Corrector died and I went looking for another device.

On paper, the Grex sounds wonderful as their selling points include the following:

• Copy protected DVD to DVD and VHS
• Copy protected VHS to DVD and VHS
• Record Protected TV channels from Satellite or Cable Receiver, SetTopBox, PVR, DVR, TiVo
• Capture protected VHS and DVD with PC Video Capture Card
• Interconnect any Macrovision sensitive devices like Video Projectors, HDTV and LCD monitors

I decided to take the plunge and order the unit.

The first tape I used as a test was a copy of The Big Hit (1998) that was lying around. I decided to try to capture one of the trailers at the beginning of the tape, John Carpenter's Vampires (1998). This is where I saw that the device actually does not handle Macrovision protection well at all.

I quickly noticed that when there is a flash or quick cut a video distortion occurs each time. This is not acceptable at all. I wondered if this was an issue with the capture card during the capture phase? Nope, the monitor was displaying the same issue with the distortion. I started to pull out some old gear for testing. I switched monitors, vhs decks, capture cards, av cables and televisions with no difference. There is clearly an issue when the Grex is part of the video chain.

I thought this might be an isolated incident with the tape itself so I made a full capture of Pumpkinhead (1988) as I knew there are many lighting scenes and this would be a good test case. Same issue once again. Distortion occurred on every lightning strike.

I decided to contact their email technical support but that proved quite pointless. They are asking how I am hooking up the device as this will somehow change a flaw in their design. This is a dumb device; you feed it a protected input and it spits out the unprotected output. The simplicity is where the issues are. There is no way to make any adjustments. The unit is just supposed to work but clearly in my case it does not.

There is really nothing else more to do here. The technical support takes it a very long time to respond to issues and in my case kept asking me questions that I already provided in my original correspondence. The fact that I am now getting mail delay failures from their mail servers does not bode well.

The relatively high price given shipping and currency conversion is very disappointing. I have it packed up and am sending it back in for a refund, as it does not work for my purposes.

A time based corrector is the real solution to the issue at hand as it will strip the signal and rebuild the frame thus fixing many issues and as a side effect eliminate any copy protection. The only problem is that they’re expensive, good ones are hard to find and the poor devices are the ones most readily available.

Here are some frame captures illustrating the issue.

Grex pcb for those who are interested.  Notice the Atmel ATtiny microcontroller and low quality capacitor.