Topfield PVR review - any news?

[musukebba]

Rasczak -any news on the Topfield you picked up the other day?

[Rasczak]

any news on the Topfield you picked up the other day?

Still waiting on the b***** thing.

[musukebba]

No problem - thought you had it already :-(

[musukebba]

Bump... they given you one yet?

[Rasczak]

Apologies I must have missed your post musukebba - I received the Topfield 5800 about a month ago and have been comparing the lossless capture aspects against the quality achieved by various other means: Sky+, ES20D and GXD500. I am not planning to write a review for the forum (unless there is significant interest) as the process has failed my quality requirements.

However if there is something specific or a general area you wish to discuss I would be happy to do so.

[plaver]

Originally Posted by Rasczak

Apologies I must have missed your post musukebba - I received the Topfield 5800 about a month ago and have been comparing the lossless capture aspects against the quality achieved by various other means: Sky+, ES20D and GXD500. I am not planning to write a review for the forum (unless there is significant interest) as the process has failed my quality requirements.

However if there is something specific or a general area you wish to discuss I would be happy to do so.

I would be interested in reading your review, if you decide not to write the review, I would still be interested into knowing why it failed you 'quality requirements.' I have narrowed my purchase down to either the Inverto (must fix skipping issues) or the Topfield (latest update must fix all known issues) the one machine that is coming up on the rails is the HUMAX, Sept 05 in the Launch date as you know these things have a bad habit of slipping.

[Rasczak]

I would still be interested into knowing why it failed you 'quality requirements.' I have narrowed my purchase down to either the Inverto (must fix skipping issues) or the Topfield (latest update must fix all known issues)

If your planning to get it as a PVR then it is an excellent machine - especially if you download some of the more-popular TAPS (such as JAG's improved EPG which effectively makes it almost as flexible/powerful as a TivO). And quality wise it performs well - although in side by side comparisons I considered by Sony GXD500 is have marginally better picture quality via the tuner - but it was extremely close.

With regard to menus and EPG data though I considered the Topfield to be sluggish - data that loads instantly on my Sony/Panasonic DVB-T gear first comes up with a "Loading..." screen on the Toppy. And menu data comes and goes although JAG's EPG TAP solves the worst of this. To be fair I am comparing it to the best Freeview boxes out there at present though...

There is a good review in the current What Video magazine - well worth picking up a copy if you're interested.

If I was buying a Sky+ like PVR now then I would buy the Topfield 5800. However I got the machine to investigate the 'lossless recording' aspects, i.e. use the machines USB connection to copy the DVB bitstream to the PC, conduct a transfer into Programme Stream without re-encoding and then burn to DVD with the aim of achieving quality identical to the original broadcast. It is in this aspect it 'failed' to meet the standards I wanted.

[musukebba]

Thanks for the brief review.

Originally Posted by Rasczak

However I got the machine to investigate the 'lossless recording' aspects, i.e. use the machines USB connection to copy the DVB bitstream to the PC, conduct a transfer into Programme Stream without re-encoding and then burn to DVD with the aim of achieving quality identical to the original broadcast. It is in this aspect it 'failed' to meet the standards I wanted.

There's a few "aspects" there - can I ask which one(s) failed and what the standards were? I can understand the process being more fiddly than the comparable HDD-DVDR, but if there wasn't any re-encoding and DVD playback was on a good player then it should be faithful to the original Freeview picture quality.

[Rasczak]

I can understand the process being more fiddly than the comparable HDD-DVDR

The core process wasn't too bad - USB to PC, Project X lossless output, TMPGEnc MPEG Editor (Lossless editing) and then TMPGEnc Author to DVD-Video. That really isn't too much different from my normal process of DVDR>TMPGEnc Editor>TMPGEnc Author.

However correction of problems was what made the quality unacceptable.

I can understand the process being more fiddly than the comparable HDD-DVDR, but if there wasn't any re-encoding and DVD playback was on a good player then it should be faithful to the original Freeview picture quality.

Yes - you would have thought so. However there are a number of issues:

Picture Quality
In theory the lossless picture when on DVD should look identical to the Freeview transmissions (bar scenes that have been re-encoded for editing purposes). It's not - there is a slight, but noticeable, "Shimmering" effect that seems to crop up frequently. If you watch the recording on the Topfield itself you cannot see this during playback. Likewise it is not visible on recordings made on the Sony GXD500 (the ES20D was not available when I did the testing - but I have not encountered it). Yet it is there when you use. Where does it come from: Project X? I am assuming not as it's still there when you use PVAStrum so that doesn't really help. I suspect it's more down to a different approach to handling Programme Stream and Transport Stream data.

Naturally it is possible to re-encode the image to resolve this problem: a found a number of filters that managed to reduce this problem - but all required the material to be re-encoded. The extent of the shimmering meant partial re-encoding is not really an option.

Lip Sync
My main DVD players are the Denon 3910 and Arcam DV79. Neither are particularly happy with the converted recordings. On both devices a lip sync error is present - and it is distorted and not displaced which makes it impossible to deal with by audio delay devices. Not all DVD players showed this (indeed most didn't) and it undoubtably is influenced by the unofficial GOP lengths used in DVB-T transmissions. Even using TMPGEnc Editor to re-encode problem GOPs did not solve this - largely due to a failure by Project X to convert 100% successfully from TS to PS.

Tests
Ironically cheaper devices do not seem to show the problem although some (especially elderly ones) do seem to reject the discs. Here are the devices I have tested:

Denon 3910 - Lip Sync problem and shimmering
Arcam DV79 - Lip Sync problem, shimmering and occasional freeze
Pioneer 868i - Lip Sync problem and shimmering
Sony GXD500 - No playback problems
Panasonic ES20D - No playback problems
Panasonic E95 - No playback problems
Panasonic S75 - No playback problems
Sony DAV530 - Will only play selective discs
Toshiba 210 - Will only play selective discs
Philips DVDR615 - No playback problems
PC (WinDVD/TMPGEnc/PowerDVD) - No playback problems

...obviously all devices are properly callibrated/setup. The fact it wouldn't play properly on either of my two major devices was a big problem for me.

So all in all Picture Quality was unacceptable as was audio sync - hence the reason why you can see I rejected the process. Both can be solved by a full re-encode - but if you're going down that route then there are better alternatives. Hopefully that will answer your question!

[musukebba]

That's very clear, and certainly are interesting findings.

Shame really though. As you say, the high end players are obviously not happy with the converted PS structure. Were you recording Freeview transmissions which have a standard DVD resolution (eg 720 x 576)? Perhaps the moire shimmering (if that's what it was) was due to the player trying to adjust to a non-standard picture 'composition' like some of the rubbish that's broadcast on ITV2. Sometimes the daft MPEG2 headers (15 Mbps) found in the TS can put a player off. Otherwise, I presume that other, less desirable, aspects of the PQ of the more DVB-compliant lower end players would preclude their use in your personal viewing.

I agree that the audio synchronisation of Freeview transmissions seems to be very difficult to maintain, even with sophisticated programs like Project X. It seems to have a problem finding audio syncwords in the way that some Freeview boxes handle the saved transport stream, even though the original recording plays without problem.

I guess you may have come to the end of the road with the Topfield and have better things to consider, but there's a couple of other DVB-T apps that you might like to try. VideoReDo has a solid converted-PS fixing routine which copes with even Hauppauge driver glitches, and anything left over can be cleared through MPEG2VCR which has excellent GOP conversion tools to finish off.

Nevertheless, thanks for performing a valuable and quite extensive series of comparative tests, investigation and review.