What is the Panasonic TX-48AS640?
So now it’s the turn of Panasonic’s AS640 to come under the AVForums microscope.
Panasonic TX-48AS640 Design & Connections
Even with the slightly unusual cut-out base stand attached it’s still extremely light, however, especially coming from the incredibly heavy AX802. We were slightly miffed that the AS640 only has inputs for 3 HDMI sources but at least two are downward facing, and one of those is your ARC (Audio Return Channel) compliant port for your soundbar or AV Receiver. The third HDMI connections faces out sideways and is much too close to the edge to prevent wires poking out without use of some sort of adapter. Also on the side are 2 USB ports and a headphone jack, whilst a Scart socket and component terminals complete the rear facing connections. Naturally you also get a Freeview HD tuner and a digital audio out.
Panasonic TX-48AS640 Menus
Panasonic TX-48AS640 Features
Panasonic TX-48AS640 Test Results
Even when setting the Contrast and Brightness controls, it was pretty obvious that the greyscale tracking was already in pretty good shape. Measurements revealed that green was a little dominant and red energy slightly lacking but there was still a good degree of neutrality. Given the capabilities of the panel and our dark room conditions, we targeted a gamma response of 2.3 and the 2.4 pre-set was actually very close to that. The pre-adjusted colour performance was even better with over-saturated green and blue primaries over-saturated and red being the opposite the only points of note.
Panasonic provides all the tools for the job, with 10-point Gamma and White Balance controls and a full colour management system, and it proved fairly easy to get things how we want them. We hardly had to touch the 10-point gamma controls, as it happened, as the equivalent White Balance controls were extremely effective. With a highest delta Error measuring just 0.38, we really have no concerns whatsoever in this department.
A backlit panel brings with it the promise of all manner of advantages over the edge-lit equivalents. First and foremost, it should make the job of dispersing light more evenly across the screen an easier job and the AS640 was very admirable in that regard, indeed. In fact, it was better than the flagship 4K AX802 in this regard, which was particularly evident when showing full – or fullish- one coloured screens. The AS640 also has an effective dimming system, that seemed to act like the equivalent of the AX802’s ‘Standard’ setting, although ‘Adaptive Backlight Control’ is a simple On/Off deal on this TV. With it engaged, we got averaged black measurements of 0.055 cd/m2 from a chequerboard pattern, giving us an ANSI contrast of around 2,200:1 when set against averaged peak whites of about 120 cd/m2. That provides for very impressive black levels in almost all circumstances that are really helped by the fact the screen is a uniform black.
The first thing to deal with here is a very odd quirk. Without the Intelligent Frame Creation (IFC) setting engaged at all, content via a 50Hz signal is near unwatchable owing to a very distracting judder. We at first suspected it might have been that the Film Cadence mode was set to on and the AS640 was treating our TiVo’s 1080i50 signal as progressive, but it’s not that. We took our K-10 to the screen to measure the screen refresh but it was generally around 100Hz (as expected) so we’re left clutching at straws at to what is the cause. The effect looks like what you get when you see a shoddy 60Hz to 50Hz conversion so perhaps 60Hz is what the TV is ‘expecting’ by default. Whatever the cause, it needs to be addressed. That said, we commissioned a survey that concluded more than half of the UK public never change any settings, which will mean most folks will be watching the AS640 in the Normal Viewing Mode which has IFC at Max by default. That causes its own issues but it’s preferable to the jerk-fest with it off. In True Cinema it’s on ‘Min’, at stock settings, so it’s not likely to be something that is going to cause much consternation but it’s a strange one indeed. We have fed back the issue to Panasonic and we'll update the review if and when we hear back from them.
By switching in to the Game Mode from the Options submenu in the Picture Menu, it is possible to reduce input lag down to 57 milliseconds, bar Dynamic, which is slightly lower at 52. Neuther figure is likely to thrill a really competitive gamer but it proved sufficient for our trivial single player pursuits. You can get Dynamic in to some sort of usable state with the picture controls but for 5 milliseconds, we’ll pass.
• Standby: 0W
The following measurements were taken with a full screen 50% white pattern:
• Out-of-the-Box – Normal Mode: 61W
• Calibrated – Professional Mode: 58W
• Calibrated - 3D Mode: 103W
Panasonic TX-48AS640 Video Review
Panasonic TX-48AS640 Picture Quality - 2D
The compromise in Panasonic not going with their usual IPS type panels is in viewing angles. To be fair, in terms of blacks washing out, the AS640 actually fares very well at more acute watching positions but the colours fade quite noticeably from more than thirty degrees off-centre. This probably won’t be an issue if you put the TV in a corner of the room but if it’s in the middle of a wall, those not in the box seat may suffer a little.
As we’d expect from an LCD/LED TV, images – static ones, in particular - look extremely sharp and detailed and the capability of the panel to go very bright means you can expect some very vivid (in a good way) pictures which look a treat with the likes of a well shot nature documentary. The long and short of it is, we really enjoyed our time with the TX-48AS640 and we hope Panasonic sees fit to extend its range to include more panels like this going in to 2014, beyond a ‘special’ model of potentially limited availability. Oh, and if you skipped the ‘Test Results’ section of this review (how could you?), remember that you will need to put/leave IFC in its ‘Min’ setting when watching broadcast TV or your DVDs!
Panasonic TX-48AS640 Picture Quality - 3D
- Great blacks
- Good dimming system
- Near perfect colours
- Generally strong video processing
- 3D has loads of pop
- Solid Smart TV features
- Judder issues with 50Hz content without IFC on
- Very mild 'dirty screen effect'
- Colours wash out off-axis
Panasonic TX-48AS640 (AS640) LED TV Review
Like just about everyone else, Panasonic ships a choice of two remotes with their Smart TVs. The standard one is fine, if a little outdated looking, but the other gives you the opportunity to test out voice commands and searches – the latter of which works really well. The Smart TV platform, itself, has two notable additions in Freetime and myStream, bringing all the major UK catch-up services and a personalised scrolling screen of recommendations with them, respectively.
It wasn’t just with the Smart TV functionality where the AS640 performed, however. This TV has it where it really counts – in the picture quality department. The 48AS640 is blessed with a panel boasting great contrast performance, natively, and also a very decent local dimming system which improves it still further.
Once calibrated, colours were supremely accurate in the True Cinema mode - not that they were bad without adjustment – and the generally excellent screen uniformity meant we could enjoy the pictures on offer more or less free of distraction. There is a bug that means you’ll need to make sure IFC is set to ‘Min’ when watching any content sent at 50Hz but since it’s on by default, it’s not something many will come across. The Panasonic AS640 is just as good in 3D, also, with the active shutter technology providing images that really stand out.
At its current asking price of £750, the 48-inch Panasonic AS640 is a really good buy as it’s a great all-round TV. Once, or if, the price heads back up north to its suggested retail of £1,000, it starts getting in to tougher competition but it would still come Recommended.
Contrast/Dynamic Range/Black Level
3D Picture Quality
Ease Of Use
Value for Money
Our Review Ethos
To comment on what you've read here, click the Discussion tab and post a reply.