Integra DTR-30.1 AV receiver review
Just when you think that surround sound standards have settled down, Dolby introduces yet another. Called Dolby Pro Logic IIz, it first appeared in an Onkyo receiver (Onkyo is to Integra what Toyota is to Lexus). This was rapidly followed by Integra, with its DTR-30.1 home theatre receiver.
But that is not all there is to this receiver, of course. It has a far more radical innovation than Dolby Pro-Logic IIz: it has recognised and implemented major changes owing to HDMI. Until now, HDMI-equipped home theatre receivers have had these connections squeezed onto otherwise unchanged back panels.
This receiver embraces HDMI as superseding analog connections. So it has an amazing six HDMI inputs, including one on the front panel, but only two component video inputs. It retains a full set of multichannel preamplifier outputs in case you want to upgrade your amplification, but drops analog multichannel inputs. After all, HDMI carries multichannel sound in digital format, so why not?
But perhaps Integra has gone just a little too far by leaving out S-Video inputs completely. If you have a source device in your system that relies upon S-Video, then this is probably not the receiver for you. The unit will convert the other analog video inputs to HDMI, allowing you to use a single HDMI cable to connect it to your video display.
The receiver also has as full a range of connections to allow integration into a home automation system as I have ever seen.
Otherwise, the receiver is fairly conventional, offering seven 90 watt power amplifiers which can be configured according to your preferences (including driving Zone 2 speakers), automatic room and speaker setup using the supplied microphone and built-in test tones, and decoders for all audio standards including the new ones provided by Blu-ray.
The other exception to that conventionality is the Dolby Pro-Logic IIz that we have mentioned. The original Dolby Pro-Logic and Dolby Pro-Logic II were both intended to produce surround sound from two channel signals. IIx also added a centre rear channel for 5.1 signals, and likewise IIz works with both stereo and 5.1 inputs, plus 7.1 channel inputs.
What it does is extract from any of these signals are sounds that it thinks would normally come from overhead, such as certain elements of room ambience, and feeds them to a pair of front ‘height’ speakers. These are supposed to be installed up high on the front wall of your listening room, slightly inside of the location of the regular front speakers.
How it works out what parts of the sound should come from on high is not very clear. Dolby says that it looks for sounds that are equally present in the different channels, but that would not apply to stereo signals.
Still, the real test is what it actually did. I moved my centre rear speakers to the front of the room, mounting them on the wall up high, and allowed the receiver’s automatic calibration system to configure the system for 5.1 + ‘height’ channels.
The first thing I can say is that the receiver delivered just the type of high performance I’ve come to expect from Integra receivers. It worked smoothly and powerfully, and it also had a wealth of setup options (with so many options, ease of use suffered just a little in the early stages).
The Dolby Pro-Logic IIz processing certainly did no harm to the sound, but rarely did much good either. Switching between the DPLIIz and DPLII, only the most subtle of surround sound changes were apparent. It was mainly in the form of a greater sense of ‘air’ in music. With movies – including action scenes on Blu-ray – there was no effect at all that I could put my finger on.
With the addition of two additional channels of power amplification, this unit supports a full 9.1 channel system (that is, you can have both the front height speakers and the centre rear speakers). I think that may be a pair of speakers too far.
But don’t let that put you off. You can expect Dolby Pro-Logic IIz to appear in all future models of receivers, and you are free to use it or ignore it. The Integra DTR-30.1 is actually more interesting in the changes to accommodate the increasing presence of HDMI. Changes that are for the most part very sensible.