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mito
05-Sep-2006, 04:37
I'm looking forward to buying a home theater in the $500 range.

I'm interested in the Frequence Response figures.

Some say 25Hz-21KHz and others 35Hz-41KHz.

I'm interested in good bass and overall sound quality. Which of the above frequence response will provide better overall quality? (bass and treble).

Thx.

ninelven
05-Sep-2006, 05:04
For $500, you will be hard pressed to beat the Onkyo HT-S790.

mito
05-Sep-2006, 05:39
please elaborate.

thx.

Ty
05-Sep-2006, 06:01
$500 for what? Everything?

How many speakers do you want?

Oh, and I doubt either of those two choices will matter much but if I had to choose, I'd go with the first one.

RobertR1
05-Sep-2006, 06:53
I go with the first one. The low will mean you get bass in the lower ranges which is good. If you watch a lot of movies, the bass is a big deal.

mito
05-Sep-2006, 07:01
$500 for what? Everything?

How many speakers do you want?

Oh, and I doubt either of those two choices will matter much but if I had to choose, I'd go with the first one.

yes, a 5.1 system with a good subwoofer.

dvd player is not required, although one with an hdmi interface would be welcomed.

_xxx_
05-Sep-2006, 07:13
I'm looking forward to buying a home theater in the $500 range.

I'm interested in the Frequence Response figures.

Some say 25Hz-21KHz and others 35Hz-41KHz.

I'm interested in good bass and overall sound quality. Which of the above frequence response will provide better overall quality? (bass and treble).

Thx.

None of those is real. Human ears can hear anywhere between 20Hz and 20KHz (or rather 15-16KHz for anyone out of the teens). But the one with up to 41 KHz should give you crisper highs, while I doubt you'll be able to hear anything below 35Hz anyway.

Simon F
05-Sep-2006, 09:39
But the one with up to 41 KHz should give you crisper highs
That sounds like people who think aliased images look crisper :razz: ...As in aliasingwhile I doubt you'll be able to hear anything below 35Hz anyway.
..but you may feel it. :-)

_xxx_
05-Sep-2006, 09:57
Hehe :) Since the sampling rate needs to be at least double the sampled frequency, 41K will give him up to 20.5 KHz audiable. Nyquist and all, y'know it all for sure...

If you filter the high frequencies out, that woudn't be comparable to AA but rather a cheap blur filter.

breez
05-Sep-2006, 10:03
Note: manufacturers' spec sheet claims about frequency response are very unreliable.

arjan de lumens
05-Sep-2006, 11:59
Hehe :) Since the sampling rate needs to be at least double the sampled frequency, 41K will give him up to 20.5 KHz audiable. Nyquist and all, y'know it all for sure...

If you filter the high frequencies out, that woudn't be comparable to AA but rather a cheap blur filter.

Umm, sample rate and frequency response are not the same thing and not even that closely related. Nyquist etc concerns itself with the limitations of what a discrete-time signal can represent, while frequency-response statements like these concern themselves with continuous-time signals. As I understand it, if a manufacturer claims 41 KHz frequency response, I would interpret it as if they are (or claim to be) able to accept a clean 41 KHz sine wave in from whatever source (analog input, or D/A converter with a sample rate of >82 kHz) and from that produce a clean 41 kHz tone out. The 41 kHz limit would then presumably arise from limitations in the analog sections of the setup, rather than a D/A converter limitation.

_xxx_
05-Sep-2006, 12:07
I don't know which is meant, but I can hardly imagine a $500 unit ever being able to correctly reproduce 40+ KHz analog signals. Nor do I see 41 KHz reproduced coming from a CD with just 44.1 KHz sampling rate anyway.

The response is, you feed it a Dirac impulse or a step and measure the overall spectrum/amplitudes of the output signal with a good spectrum analyzer. Nothing to do with sinus, since even a "clean" sinus can always be represented as a sum of harmonics (Fourier etc.).

EDIT: and I referred to the sample rate (assuming he was talking about digital signals) because the highest frequency you can reproduce is (minimum) half of the sampling frequency according to Nyquist. So for "acceptible" reproduction of 41 KHz you'd need min. 82 KHz sampling rate as you said above.

arjan de lumens
05-Sep-2006, 12:35
I don't know which is meant, but I can hardly imagine a $500 unit ever being able to correctly reproduce 40+ KHz analog signals. Nor do I see 41 KHz reproduced coming from a CD with just 44.1 KHz sampling rate anyway.

The response is, you feed it a Dirac impulse or a step and measure the overall spectrum/amplitudes of the output signal with a good spectrum analyzer. Nothing to do with sinus, since even a "clean" sinus can always be represented as a sum of harmonics (Fourier etc.).

EDIT: and I referred to the sample rate (assuming he was talking about digital signals) because the highest frequency you can reproduce is (minimum) half of the sampling frequency according to Nyquist. So for "acceptible" reproduction of 41 KHz you'd need min. 82 KHz sampling rate as you said above.

The Dirac pulse will give you an "impulse response", while the step signal will give you a "step response". They are actually quite different, and neither is the same as a "frequency response", even though (if your system is linear) there exists a 1:1 mapping between all three of them.

A clean sine wave contains no harmonics at all and and can certainly NOT be constructed as s sum-of-harmonics; the Fourier transform of a sine-wave is a single Dirac pulse. Any half-decent DSP book will explain this to you (http://www.dspguide.com) in excruciating detail.

For a CD-type medium (being a discrete-time signal with a fixed 44.1 kHz sample rate), you obviously cannot represent frequencies above 22.05 KHz, however you could perfectly well be running other sources than plain CD -- SACD, DVD-Audio, and output from a computer sound card (all of which sound as if they could be quite relevant for a home theater) can all easily reach sample rates far above 44.1 kHz, making the frequency response at >22 kHz a fair bit more relevant than for CDs.

_xxx_
05-Sep-2006, 12:47
The Dirac pulse will give you an "impulse response", while the step signal will give you a "step response". They are actually quite different, and neither is the same as a "frequency response", even though (if your system is linear) there exists a 1:1 mapping between all three of them.

The quality equipment is supposed to be linear at least in the "interesting" range for audio.

A clean sine wave contains no harmonics at all and and can certainly NOT be constructed as s sum-of-harmonics; the Fourier transform of a sine-wave is a single Dirac pulse. Any half-decent DSP book will explain this to you (http://www.dspguide.com) in excruciating detail.

Nope. A simple example, sum of two sinus signals with the same frequency.

For a CD-type medium (being a discrete-time signal with a fixed 44.1 kHz sample rate), you obviously cannot represent frequencies above 22.05 KHz, however you could perfectly well be running other sources than plain CD -- SACD, DVD-Audio, and output from a computer sound card (all of which sound as if they could be quite relevant for a home theater) can all easily reach sample rates far above 44.1 kHz, making the frequency response at >22 kHz a fair bit more relevant than for CDs.

Surely right. Though most of the material used nowadays isn't originally recorded in anything better than the CD-quality, that's why I referred to 44.1 KHz.

MuFu
05-Sep-2006, 13:29
No idea about recommendations since the US market is so different to the UK, but for $500 I would expect that you are better off going with a receiver plus separates than a "home theatre in a box" (HTIB) system.

...even if it means going without a sub till you can afford a decent one.


Nope. A simple example, sum of two sinus signals with the same frequency.

That isn't really a sum of harmonics though. It's just f + f.

_xxx_
05-Sep-2006, 14:14
You're right. It's been a while since I worked with this stuff, meh.

All that aside, let's not kill the topic with this :)

nelg
05-Sep-2006, 16:19
http://cgi.ebay.co.uk/Yamaha-DSP-AX620-5-1-Home-Cinema-Amplifier_W0QQitemZ300024062303QQihZ020QQcategoryZ 72406QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

EBay can be a great source for audio equipment.

_xxx_
06-Sep-2006, 08:00
Oh yeah, one more thing: DON'T buy anything you didn't test yourself. Regardless of what it says on paper, your own ears are always the best judge.

pascal
06-Sep-2006, 15:24
Denon has some of the best HomeTheater-in-a-Box available. http://www.usa.denon.com/ProductDetails/HomeTheaterSystems.asp

Focus on quality :yes:

JBark
06-Sep-2006, 15:57
I've never used a Denon HTiB, but I can say that their receivers are top notch. I've had 2, and both were excellent.

If you were in the US (I don't think you are?), then I'd recommend a combo like this:
1) Nice 5.1 Denon in the $200-300 range
2) Fluance AV-HTB+ (http://www.fluance.com/fluanceavhtb.html) - $200
3) PartsExpress 12" Sub (http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=300-635) - $120

All told that would run in the $500-$600 range. Don't be fooled by the cheap prices on the speakers, every review of them is excellent. They aren't the best speakers ever, but you get much more than you pay for.

I've got a 7.1 setup that consists of a Denon 3803, Fluance SX-HTB+ (http://www.fluance.com/fluan5speaks.html) (plus 2 extra speakers), and the older model PE sub. I've yet to find anyone that wasn't shocked by the fact I paid less than $1K total, it sounds that good. And yes, it sounds very good even at ear-bleeding levels with the bass shaking the house :)

mrboo
06-Sep-2006, 22:10
None of those is real. Human ears can hear anywhere between 20Hz and 20KHz (or rather 15-16KHz for anyone out of the teens). But the one with up to 41 KHz should give you crisper highs, while I doubt you'll be able to hear anything below 35Hz anyway.

Hear?..No......But FEEL?.....Yes.. ;)

MuFu
07-Sep-2006, 01:13
Hear?..No......But FEEL?.....Yes.. ;)

Really depends on how good the sub is. If it's super crappy you won't hear or feel much below 35Hz.

While we can only really hear frequencies above 20Hz, all but the very best subs will produce some audible output when reproducing a 20Hz sine wave, just because of distortion.

nelg
07-Sep-2006, 02:44
All told that would run in the $500-$600 range. Don't be fooled by the cheap prices on the speakers, every review of them is excellent. They aren't the best speakers ever, but you get much more than you pay for.

I've got a 7.1 setup that consists of a Denon 3803, Fluance SX-HTB+ (http://www.fluance.com/fluan5speaks.html) (plus 2 extra speakers), and the older model PE sub. I've yet to find anyone that wasn't shocked by the fact I paid less than $1K total, it sounds that good. And yes, it sounds very good even at ear-bleeding levels with the bass shaking the house :)

Thanks for the review of the Fluance speakers. I was considering them myself.

Skrying
07-Sep-2006, 02:55
Frequenecy response is honestly one of the very last things I'd be concerned with.

Sound signature probably being the first. Crisp highs, clean lows, and impactful lower mids and fun upper highs, whatever you like to hear.

Honestly, audio is far to subjective to have someone point out a good setup.

pascal
08-Sep-2006, 14:48
Sound signature probably being the first. Crisp highs, clean lows, and impactful lower mids and fun upper highs, whatever you like to hear.This reminds me one demonstration of a B&W 800 series large towers I listened.
Unbelievable.

Vadi
09-Sep-2006, 12:56
I'd build a set of these: linky to 5 speakers below 100$ (http://zaphaudio.com/audio-speaker18.html).
Use your HTPC as a preamp/processor (an X-Fi costs about 90$) and build some digital amps (http://www.41hz.com/). For the above speakers you'll need one AMP3 (25$) for two speakers.
For about 200$ you can get a nice matching DIY transmissionline sub (http://www.lautsprechershop.de/hifi/index.htm?/hifi/ct220_en.htm) too.
:)

edit:
Opps, I forgot you'll need a PSU for your amps.
Also a good update would be adding a second sub.

mito
09-Sep-2006, 20:21
thank you guys.

after doing some research, I opted for the onkyo ht-s790.

mito
03-Oct-2006, 22:24
just connected my audigy 2 zs to my onkyo through optical spdif.

wow.