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New Teac DVD Receiver DR-H358i and Predecessor DR-H300(DAB)

 
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newcoppiceman



Joined: 15 Jun 2009
Posts: 13
Location: Woking, Surrey UK

PostPosted: Thu Oct 22, 2009 8:11 am    Post subject: New Teac DVD Receiver DR-H358i and Predecessor DR-H300(DAB) Reply with quote

Do you have a Teac DR-H358i or DR-H300 (with or without the -DAB suffix)? Are you thinking of getting one?

The DR-H358i is a successor to the nice-but-flawed DR-H300DAB which Teac advise has now been withdrawn. It comes with an iPod dock which connects via the front-panel USB socket and, perhaps oddly for a 'reference system', incorporates a digital clock with timer, alarm and sleep functions.

If you have a DR-H358i I'd be interested to know whether they've fixed the various design flaws with the DR-H300DAB; if you're thinking of getting either you need to read the following, based on living with a DR-H300DAB for two years (I also recently bought a spare via eBay which exhibits the same problems - just like two others I tried at time of original purchase):

Mad 1. Noticeable hum/buzz on phones output, accompanied by clicks when changing sources. Late at night I often use phones to listen; quiet passages on ANY source (I often listen to Freeview TV via AUX 1) WILL reveal a fixed-level (doesn't change with volume or mute on/off) of annoying hum and buzz. Simply unforgiveable in a unit built around digital sources.

Mad 2. NON-RANDOM mutes on DAB. You WILL hear mutes (anything up to 5 seconds) even with a decent RF signal level. The DR-H300DAB uses the Gyro 1122 DAB module and - to their credit - its manufacturers have willingly engaged with me regarding the problem of any (and they are actually quite frequent) change of transmitted bitrate on a BBC service (eg Radio 4 from 128kbps stereo to 80kbps mono) causing a mute across ALL BBC services on the same DAB multiplex, so that's Radio 1, 2, 3, 4..., as the little Gyro module has a headache and goes back to square one to sort itself out!

This is not typical behaviour for a DAB radio, indeed some (eg Pure Evoke-1) are very good at handling these bitrate switches and you hardly notice them on the switched service itself. A feature of this shortcoming, is that if you have muted the DR-H300DAB, it will promptly unmute. This is what the nice man from Gyro said in his last e-mail: "While we need more tests to validate, I would like to thank you for understanding and you did help in a way that prompted us in improving next tuners!" You might think that this was more constructive than a confused letter from Teac's UK Service Manager wherein he stated that "...we have absolutely no doubts about the quality or performance of the DRH300DAB unit... ...why not just settle back and enjoy the sound reproduction of the system instead of ghost-hunting for faults with it."

Mad 3. CD playback. If you play CDs from start to finish, the start of around 40-50% of all tracks is clipped - by half a second or so. It does vary with CDs, but after months of listening to loads of CDs, that's where I'd put the percentage. This is really annoying. If you press skip back the track will then play cleanly. The problem is usually repeatable for affected tracks. This may be happening because it’s a DVD player first and a CD player second - it also takes an age to read a CD’s TOC (table of contents) when the disc is first loaded. I have a service manual for the DR-H300DAB and plan to bring out temporary connections to the circuit boards to see where in the signal chain the clipping is present - including right back to pins 224/226 of the MediaTek MT1389HD chip (which is as far back as I can go in the analogue domain). The MT1389HD chip forms the core of the DR-H300DAB's DVD/CD functionality - because it does so much, it's known as a 'system-on-a-chip' (SOC). If I can find a cheap one, I'll also try an external DAC. My ears are too old to be 'golden' so I don't have one already - but they still know when something ain't right! MediaTek have been helpful in correspondence and say they don't think the problem is with their chip.

Wink 4. CD play problems solved early 2009 (15 months old) after I fitted a new Sanyo SF-HD65 optical pickup assembly - not a difficult job.

Smile 5. We usually watch DVD films on a Saturday night and the DR-H300DAB has behaved impeccably in this regard - but I must stress that we use the Scart RGB output to feed our Panasonic 28" widescreen CRT TV (flat panels aren't there yet if you want to watch natural pictures, in my opinion)...

Exclamation 6. ...Problems have been reported by other DR-H300DAB users with the HDMI output and one retailer has stated: "There were serious de-interlacing problems that led to visible lines across the screen, especially during movement. Due to this, we suspended sale. We are yet to see this problem rectified but we do not feel that the quality of the video output is suitable to pass on to consumers."
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ascanius



Joined: 21 Mar 2010
Posts: 2

PostPosted: Sun Mar 21, 2010 12:48 pm    Post subject: DRH358i experiences Reply with quote

I owned a DRH300DAB for appr. a year, when the DAB receiver broke down with symptoms that I would take as a firmware error. It was not possible to recover from the error by any reset procedure. The dealer mentioned that another 300 was returned with a similar problem - but that's another strange story. The point is that the TEAC's, accoring to the dealer, is not repaired here in Denmark, but replaced if they break down. And since the 300 has been discontinued, I was offered a DRH358i as replacement. Let alone that my 300 was blank, and the 358 onlky comes in black... here are my comments on the 358 - the positive first:

- It sounds absolutely fantastic!
- The ticking sound from the optical drive of the 300 model has gone.

And for the negative:

- There is a serious problem with the volume control when operating it with the front panel knob: It's temporarily irresponsive, it starts turning up when you want to turn down; it can even enter a state where it just increases volume by itself, without being touched. I quickly turned in the first 358 due to this problem, at had it exchanged with the dealer's demo unit. Same problem. A inexcusible design or production problem.

- The volume control only has 32 steps, which is far too few. The distance between the lower steps are far too great.

- Clicks appear in the speakers: When switching source, when toggling the volume control between step 0 and 1, and worst of all, between each track when playing a CD!! Parts of the electronics seem to have been designed by a first year engineering student.

- Mechanical hum, like from a mains transformer, appear when the device has been turned on for an hour or two.

- And, the 358 has the same anoying slowliness with the front panel source selector as the 300 has.

As for the questions rasied in the post:

- I don't use the Phones output, but just checked: No hum to hear.

- The mutes on DAB never happened to me; probably because DAB stream badwidth is not dynamically reallocated here in Denmark, as it is with BBC.

- I never experienced the "track clipping" on CD's on either the 300 or the 358.

My conclusion: DRH358i is a great product that should never have been put on the market, until the mentioned quality issues were solved, including design- n of a adequately fine-grained, reliable volume control.

Regards
Henrik Jacobsen
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newcoppiceman



Joined: 15 Jun 2009
Posts: 13
Location: Woking, Surrey UK

PostPosted: Mon Mar 22, 2010 8:46 am    Post subject: Reply with quote

Thanks for your post Henrik - very interesting. I don't think I'll be rushing out any time soon to buy a DR-H358i! I would urge you to add your comments to the customer reviews at:

http://www.amazon.co.uk/Teac-DRH358IDAB-BLACK-Micro-Player-Reciver/dp/B002TV63Z4/ref=cm_cr-mr-title

(where I've taken some flak for highlighting Teac's track record with the DR-H300DAB!)

- Haven't experienced any ticking of the optical drive with either of my DR-H300DABs but I guess a particular mechanism could have a problem.

- Interesting what you say about the volume control. Since my original post I've discovered that the DR-H300DAB volume control should be 64-step but some units are only 32-step.

The specifications for the IC used states that each of the 64 steps is 1.25dB, so 32 means 2.5dB per step, which is too coarse - 1dB is usually taken to be one JND (just noticeable difference). I discovered this after buying a second unit as a spare about six months ago. We had it in daily use for a couple of months - DAB radio, CDs, DVDs, Freeview TV/cassettes/VCR via AUX 1 and the Wii via AUX 2. It behaved fine, except for the fact that it wasn't possible to set it to our normal listening level - either too quiet or too loud!

Incidentally, p20 of the owner's manual, in describing control of the volume, may or may not include (00) and (63) after MIN and MAX respectively; I have two apparently identical manuals - one does, the other doesn't!

- With this second unit I also discovered a problem, the severity of which depends on whether you're conscious of the difference between true video pictures and film pictures (this manifests in the way movement is portrayed - there's a brief tutorial below which explains). I have a BBC promotional DVD with clips of popular sit-coms, most of which are true video as they were shot by television cameras and not subsequently converted to make them look like film. On one DR-H300DAB they play as true video (ie as intended), on the other they play as if they had been converted to "film look".

Lots more on the DR-H300DAB at:

http://www.avforums.com/forums/all-one-systems/1183262-calling-teac-dr-h300dab-owners-check-yours.html
http://www.avforums.com/forums/all-one-systems/1054589-teac-dr-h300dab-design-faults-problems-2.html

...and some useful pics at:
http://www.flickr.com/photos/38818955@N07/

Tutorial
In true video, each complete picture (every 1/25s) is composed of two interlaced fields taken by an electronic video camera 1/50s apart, during which any motion in the scene is captured. A film camera captures a scene 25 times a second* and when converted to video each interlaced field is derived from the same picture, so there is no movement between the fields. It's common these days in television production to process video-originated material to make it look like film because, for cultural reasons, we apparently prefer this, despite it being a reduced resolution mode - in the temporal (time) domain, that is, not the spatial domain. It seems odd, however, watching material we're accustomed to seeing in true video (eg Fawlty Towers) in film mode and the DR-H300DAB should play true video as true video.

*Let's leave aside the complication that movie cameras shoot at 24fps!
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ascanius



Joined: 21 Mar 2010
Posts: 2

PostPosted: Mon Mar 22, 2010 7:20 pm    Post subject: Reply with quote

Guess the bottom line is that the DRH300* comes with different hardware inside, although the devices look the same from the outside!

Funnye about the drive ticking - when I bought the original DRH300DAB, the dealer told me that there were only 2 negative things to say about it: The slow disc load time (compared to a old fashioned CD player), and the ticking from the optical drive. So, I'm sure it was not only mine... it was not a big issue, but clearly audible when you turned down the volume. Some 2 ticks per second on audio CD's.

I have never been aware of the video/film issue - I'm not that much of a video enthusiast; although I did learn that movie lovers tend to turn off the 100 Hz / 200 Hz functinality on their LCD screens, because it ruins the original 24 fps impression.

Yes, I'll consider posting my comments on the Amazon site - give me a day or two Smile
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Minimess



Joined: 24 May 2010
Posts: 14

PostPosted: Mon May 24, 2010 6:27 pm    Post subject: Reply with quote

I've had this for a week. The sound is excellent and it really does look good. It's an allrounder too... you get a whole choice of i/o and all that.

I am looking for a good speaker to go with it... any recommendations?
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