Question about THX

[Aznkiller908]

What does THX certified mean really?
I was gonna buy the sp908 from knyo but from what im reading the 705 has THX and was wondering what it does and is it worth getting for an extra $100-$200?

[emacs]

Originally Posted by Aznkiller908

What does THX certified mean really?

a THX certified device is one that passed all tests defined by THX Ltd., to deliver optimal high-quality audio. the THX certification is pretty much nullified if your room, source material, speakers, wiring or playback device are not really good.

[Durentis]

http://en.wikipedia.org/wiki/THX

[Aznkiller908]

tyvm for explaining it to me

[turboLAZER]

THX Select2 certified receivers also offer a THX post decoding processor which can be turned on or off. When turned on, it takes the Dolby Digital or DTS track from your dvd or blu-ray and tries to make it sound more like the theatrical experience by smoothing out the audio transition from one speaker to the next and by toning down the overly "bright" tones on the original track

[Aznkiller908]

but is it worth spending an extra $100-$200?

[Marcusarilius]

Originally Posted by Aznkiller908

but is it worth spending an extra $100-$200?

Yes.

[Aznkiller908]

ok just added up the price and its going to cost me an extra $400 for the receiver and speakers so the sound quality is really worth it huh?

[Durentis]

Originally Posted by Aznkiller908

ok just added up the price and its going to cost me an extra $400 for the receiver and speakers so the sound quality is really worth it huh?

No. The sp908 comes with the sr605. The SRP difference between the sr605 and sr705 is only $300. Given that you are comparing two entry-level Onkyo's, why spend significantly more for features you'll likely not be taking advantage of. And significantly better sound quality? I doubt it.

Here's a summary of what you'd get from the sr705:
- +10W per channel (irrelevant)
- THX certification (pretty much irrelevant)
- DSD Processing/Direct Mode (Support for bistreamed SACD audio, I believe)
- Phono input (got a record player to hook up?)
- 7.1 pre-outs instead of 0.1. (unless you have amps for each of your speakers, you only need the sub pre-out available on the sp908)
- Learning remote (meh)

May have missed something relevant, just use the compare feature for the sr605 and sr705 to see for yourself.

I'd say your choices in the Onkyo line are really between the sr605 or the nr905. But then, if you're not getting the sr605 (or sp908) I'd recommend away from Onkyo anyhow based on Onkyo-related posts I've read in the past.

[saprano]

i have the 705 and have no problems with it, i was just like you i was gonna get the 605 but 705 had more features and more watts(since when is more power a bad thing? ) i may not have used all of its features yet but its good to know its there and your receiver is future proof. if i had got the 605 i would have regret it, GO the for 705 youll be happy.(just look at that blue light )

[JohnGalt]

Originally Posted by Durentis

7.1 pre-outs instead of 0.1. (unless you have amps for each of your speakers, you only need the sub pre-out available on the sp908).

Depending on future upgrade plans this can be worth the money. E.g., I'm running a 5.1 setup with large power hungry mains and I do begin to hear just a bit of harshness from them right around the volume level I really enjoy (somewhere between a jackhammer and a jet plane taking off) despite driving the 5 speakers with a fairly capable AVR.

I'm probably asking just a bit more from my AVR than it is truly capable of delivering. One solution would be a solid 2-channel amp for the mains to unload the AVR which can doubtless handle the center and surrounds with room to spare. Another would be a full-on 7 channel HT amp. But either way I can spend a bunch of a nice amp to solve my issue rather than dumping similar money into a marginally better AVR.

Point being that I have some flexibility due to my AVR's pre-outs and (the audiophile guys should stop reading right here) a modern AVR makes for a *very* passable preamp and can be a nice bridge into separates if you're so inclined ... or might be in the future.

[cpgator]

The THX badge is basically like a good housekeep seal of approval. It just means that it meets certain specs. It does not mean that it is better than a non-THX approved receiver. There are many high end receivers that do not get their products THX certified, even though they exceed the specs.

I would not pay extra for the certification. There are other specs that are much more important.

[MarkMTC]

Originally Posted by Durentis

No. The sp908 comes with the sr605. The SRP difference between the sr605 and sr705 is only $300. Given that you are comparing two entry-level Onkyo's, why spend significantly more for features you'll likely not be taking advantage of. And significantly better sound quality? I doubt it.

Here's a summary of what you'd get from the sr705:
- +10W per channel (irrelevant)
- THX certification (pretty much irrelevant)
- DSD Processing/Direct Mode (Support for bistreamed SACD audio, I believe)
- Phono input (got a record player to hook up?)
- 7.1 pre-outs instead of 0.1. (unless you have amps for each of your speakers, you only need the sub pre-out available on the sp908)
- Learning remote (meh)

May have missed something relevant, just use the compare feature for the sr605 and sr705 to see for yourself.

I'd say your choices in the Onkyo line are really between the sr605 or the nr905. But then, if you're not getting the sr605 (or sp908) I'd recommend away from Onkyo anyhow based on Onkyo-related posts I've read in the past.

Absolutely! The reason I went with the 705.

[saprano]

to the op...just get the 705 forget about the thx for a second, it has more watts and more features if needed.

[Durentis]

Originally Posted by saprano

to the op...just get the 705 forget about the thx for a second, it has more watts and more features if needed.

I repeat, an extra 10W per channel is absolutely bloody irrelevant.

Read this article and then tell me just how much 'extra power' you're getting from the 705's extra 10W per channel.

[saprano]

Originally Posted by Durentis

I repeat, an extra 10W per channel is absolutely bloody irrelevant.

Read this article and then tell me just how much 'extra power' you're getting from the 705's extra 10W per channel.

wow i didnt know that thanks for the artical. so how much watts is my onkyo giving my speakers? 50watts each

[Durentis]

Originally Posted by saprano

so how much watts is my onkyo giving my speakers? 50watts each

Your sr705 has 100 watts per channel. Each speaker is powered by one channel. So, ignoring dynamic range, your Onkyo is giving each of your speakers up to 100 watts.

The point was that an sr605 at 'only' 90 watts per channel results in less than 1 dB difference by that chart. Even my Marantz sr8002 at 125 watts per channel only results in a 1dB gain over the Onkyo sr705 and a 2dB gain over the Onkyo sr605 by that chart. So comparing the power available from the best of Marantz with the entry-level Onkyo (the two extremes IMO) shows that regardless of what HT receiver you get, the watts shown are pretty much irrelevant. I didn't get the sr8002 for the 125 w/ch, I got it for (among other things) the toroidal transformer.

The only reason to buy above the entry-level receiver is for a desired feature not found on that receiver. Such as phono-in if you can make use of it (and why this doesn't start on the sr605 is beyond me), or a toroidal transformer if you want a cleaner audio signal, or additional HDMI sockets, or pre-outs if you want dedicated amps.

[MouseRider]

Remember that decibels is a base-10 logarithmic scale and not linear, so a 1dB increase is significant.

Like many things, the pure measurement of power is pretty useless without the measurement of quality at that power.

Originally Posted by Durentis

Your sr705 has 100 watts per channel. Each speaker is powered by one channel. So, ignoring dynamic range, your Onkyo is giving each of your speakers up to 100 watts.

The point was that an sr605 at 'only' 90 watts per channel results in less than 1 dB difference by that chart. Even my Marantz sr8002 at 125 watts per channel only results in a 1dB gain over the Onkyo sr705 and a 2dB gain over the Onkyo sr605 by that chart. So comparing the power available from the best of Marantz with the entry-level Onkyo (the two extremes IMO) shows that regardless of what HT receiver you get, the watts shown are pretty much irrelevant. I didn't get the sr8002 for the 125 w/ch, I got it for (among other things) the toroidal transformer.

The only reason to buy above the entry-level receiver is for a desired feature not found on that receiver. Such as phono-in if you can make use of it (and why this doesn't start on the sr605 is beyond me), or a toroidal transformer if you want a cleaner audio signal, or additional HDMI sockets, or pre-outs if you want dedicated amps.

[cpgator]

Originally Posted by MouseRider

Remember that decibels is a base-10 logarithmic scale and not linear, so a 1dB increase is significant.

Like many things, the pure measurement of power is pretty useless without the measurement of quality at that power.

A 1dB increase can hardly be detected. Some people probably couldn't even hear a difference.

[Tok]

Don't discount THX altogether.

THX has several specification for AVRs and amplifiers. They are not necessarily easy to meet despite what some say. THX is an independent body. I have more faith in an independent body that has a long history with audio reproduction related to large commercial theaters and more recently a consumer division.

THX Ultra/Ultra2 - large rooms over 3000 cu. ft
THX Select/Select2 - rooms 2000 cu. ft

The biggest thing I think people overlook is the THX sound modes. These are the biggest reason I would buy an AVR or a signal processor with THX.

I use the THX Ultra2 Cinema mode all the time on my Onkyo 805 with the THX ReEQ set to off. It creates the most realistic 7.1 soundfield over the more in your face DPLIIx.

The 805 is a beast and it is the lowest priced Ultra2 product out there. Onkyo put money into its power supply. If you have a large room go for the 805. Otherwise I would go for the 705 over the 605 since in addition to THX it also can post process LPCM 5.1 into a 7.1 signal. The 705 is only Select2 certified but it carries the same THX modes and the ability to disengage the THX ReEQ filter if you don't like the effect/cutting too much of the highs. Also the 705 weighs about 20lbs. less than the 805.