weak bass in RTi10

Tour2ma

tonyb wrote: »

I'm talking HT verse 2 channel big guy. If your running a 5 channel surround system,your using the 6th and 7th channel to bi-amp.

Gotcha... I was thinking more along the lines of AVR 5-ch HT vs AVR bi-amped, 2-ch music listening.


gp4j, comfyc, whomever,

In a passive bi-amp scheme, let's follow the amplified, full spectrum music signal sent to the tweeter of a 2-way speaker interally crossed over at 2 kHz. We'll assume a moderate output of 10W.

It is well established the HF power requirements are significantly less than that of LF. For simplicity let's assume HF power is 20% of the total, or 2W. With this music energy now passed to the tweeter it is singing like a bird.

Please explain what happens to the 80% of the energy that never reaches the tweeter.

comfortablycurt

Tour2ma wrote: »

Gotcha... I was thinking more along the lines of AVR 5-ch HT vs AVR bi-amped, 2-ch music listening.


gp4j, comfyc, whomever,

In a passive bi-amp scheme, let's follow the amplified, full spectrum music signal sent to the tweeter of a 2-way speaker interally crossed over at 2 kHz. We'll assume a moderate output of 10W.

It is well established the HF power requirements are significantly less than that of LF. For simplicity let's assume HF power is 20% of the total, or 2W. With this music energy now passed to the tweeter it is singing like a bird.

Please explain what happens to the 80% of the energy that never reaches the tweeter.

Well, for starters...

When I stated that AVR bi-amping turns 100 wpc into 50+50wpc, I didn't mean that literally, in concrete terms. I didn't think anyone would take it as such. That was a generalized statement, and was simply meant to convey the point that it's not doubling the power output in any way shape or form. It's simply dividing the wattage output that was already there. Going by your example above, it's taking that 100wpc, and turning it into 20+80 wpc.

Fact is, that division of power is going to be exactly the same no matter where it's divided...whether the stream is separated at the AVR or at the speakers internal crossover.

I'll use the same assumptions as you, for simplicities sake. Let's assume that we're using a single wiring method here...no AVR bi-amping. We're sending 10 watts to the speaker, and the tweeter requires 20% of the total power. The tweeter is getting 2 watts and the woofer is getting 8 watts. The speakers internal crossover is dictating what portion of that signal goes where.

Now, let's take that same setup and bi-amp it with our AVR. The AVR sends a full range signal to both the HF and LF sections of the XO. Is there any argument to that point? There is no crossover to set in the AVR to determine what part of the amplified signal travels down which pair of wires, and it makes no difference which pair of amp channels are connected to which section of the speaker.

For instance...the manual for my Onkyo 606 states that in a bi-amp configuration, the front L/R channels should be connected to the HF section, and the surround back L/R channels should be connected to the low frequency section. Ok...so what happens if we switch that configuration around? Nothing at all. It sounds EXACTLY the same. I've tried it personally. It makes no difference which pair of outputs on the AVR are connected to which pair of inputs on the speakers. Each pair of outputs on the AVR are putting out the EXACT same signal. The only reason Onkyo even states that the front channels should connect to HF and the SB channels should connect to LF, is to idiot proof it, and prevent thousands of people from sending them emails asking how to connect them.

Is there any argument against the fact that both pairs of outputs on the AVR are putting out the exact same, full range signal?

Knowing that both pairs of outputs are sending out the exact same signal, how is the division of the signal handled? You guessed it, it's handled by the speakers internal crossovers. The very same internal crossovers which, in a single wiring configuration, dictated that of the 10 total watts reaching the speaker, 2 watts are being allowed to pass to the tweeter and 8 watts are being allowed to pass to the woofer. In a bi-wiring configuration, the speakers internal crossovers are still going to perform the exact same task, and will go about it in exactly the same way. The only difference is that instead of using a jumper between the two pairs of outputs, you're simply sending the same full range signal through two pairs of wires, and bypassing the jumper. To simplify it, AVR bi-amping is essentially a glorified version of the jumper bar that comes stock on every Polk speaker with multiple pairs of inputs.

So what happens to the 80% of the power that never reaches the tweeter? It goes to the woofer. What happens to the 20% of the power that never reaches the woofer? It goes to the tweeter. How does this differ between bi-amping and single wiring? It doesn't. The signal is carried and processed in exactly the same way, and by the exact same components. The AVR bi-amping configuration has no effect on this process one way or the other.

Regardless of how it's connected, the speakers internal crossover is handling ALL of the signal managing duties. The AVR plays absolutely NO PART in the distribution of the signal between the different drivers and it offers NO INCREASE in total wattage reaching your speakers. Is there any argument to those points?

A few people have mentioned that replacing the stock jumpers with higher quality wire offers a bigger improvement in sound quality than bi-amping with an AVR. In my opinion AND experience, this is absolutely 100% true. I've tried "bi-amping" several different pairs of speakers with my Onkyo 606, and not once did I find there to be any kind of an improvement whatsoever. However, when I replaced the stock jumpers with some Canare 4S11, I noticed an immediate improvement in sound quality. The blend between the lows/highs was much more balanced sounding overall, I noticed a substantial drop in the background noise of the speaker(i.e. the quiet hiss/hum that is slightly audible from a speaker that isn't playing anything). These improvements were obvious after only a short time of listening. I don't even know how many times I switched between bi-amping and single wiring, and I never ONCE heard a single iota of a difference.


I really don't understand why you're arguing this point so much. The consensus of roughly 99% of the people I've seen discuss AVR bi-amping on here is that it provides no improvement whatsoever, and it's a FACT that there is no technical reason that it should have any benefits.


I don't know that I can explain it any better than that...and I'm certainly not going to try to. There's my take on it. Take it or leave it. I'm not gonna keep arguing this point, since you seem pretty stuck on your opinion of it. Just one question...have you ever actually tried bi-amping with an AVR? Just a question.

bmor

Interesting comments by all, thanks to all for taking the time. Here's another opinion on the subject, just to flail on the demised equine some more.
See post #62 & 63.

http://www.hometheaterforum.com/forum/thread/130932/passive-biamping-how-much-improvement/60

As well, I think I'm beginning to understand the nature of power ratings on these AVR's. The Pio 1325 has continous average output of 110W for 7 channels but the power consumption spec reads 400W. Based on info I've found on-line, I can expect maybe 50-70% of that 400W as available (continuous?) power, so I'm looking at somewhere between 200-280W. So driving just two channels in stereo listening I should expect close to the 2 x 110W rated output. Multi-channel will of course be much less.

GrandeBoma

so for you bi-amp experts, let's say I want to power the 3 fronts

what is the difference between:

using a 6x100w amp with 3 channels for HF and 3 channels for LF (without active crossover)
using a 6x100w amp with 3 channels for HF and 3 channels for LF with active crossovers
using a 3x200w amp with one channel powering both HF and LF (jumpers are on the binding posts)

tonyb

We still beating this dead horse ?
You talking amps or receivers ?
What kind of amps....what kind of receivers ?
What receiver pumps out 200w in all channels ?
Are you talking Bridged mode on the last amp?
Are all amps the same ?
Driving what speakers ?

You left out some detail here my man.

GrandeBoma

i am not beating a dead horse i am just trying to understand if I have got how it works

i am talking about audio theory, what are the differences in the three hypothetical scenarios but if you prefer more details, let's say for example

driving rti12 and csi5 (or rtia9 and csia6)
generic rotel/marantz/onkyo 6x100w or 3x200w solid state class a/b or class d stuff (different amps, not bridged)
what changes in the system if i use the first (6x100w) with and without xover, and what is the difference with the second more powerful amp (3x200w) in non-biamp mode

in theory the speakers should always get 200w per channel but in practice...(answer needed)?

Ron Temple

GrandeBoma wrote: »

in theory the speakers should always get 200w per channel but in practice...(answer needed)?

Your speakers will almost never see 200w. The amp is capable of 200w with 1.5 to 3db headroom rms (depending on the amp) with probably a tad more for dynamic peaks. Your speakers see what your source requires at whatever volume you are playing back. The current converted to watts required will vary depending on your speaker sensitivity, impedence and the dynamics of the material.

Example: SDA 1Cs, Carver TFM35, playing an average 90dbs at 12' LP. The Carver is rated at 250w @ 8 ohms. The 1Cs are 6ohm nominal. I was playing Alan Parsons Eye in the Sky...a dynamic track. The needles were hovering around 30w output, but along came some dynamic kick drum/high hat hits probably 10dbs or so above the average. They happened so fast the SPL meter couldn't move fast enough, but the needles were pegging on the Carver at 500w output. Sounded great and it was unclipped. If I didn't have enough headroom in the amp to handle these peaks, I would have soft clipped. If I'd been using a 100w AVR you'd never know. It just wouldn't have sounded as dynamic. It happens all the time. SDAs are demanding, as are RTi12s (though not as much). So, in a similar situation, playing similar content, a 200w amp is going to handle it much better than your 100w AVR.

GrandeBoma

still doesn't answer my question

let's say I buy a 3x200w amp and I hook it to my fronts and center's binding posts who have the jumper on (HF + LF)

then I change amp, and put a 6x100w but this time I remove the jumper, and feed 3x 100w in the HF and 3x in the LF. From pre-out I feed each signal (FR, FL and center) in a pair of amp in with a Y cable. What changes, from electromagnetism's standpoint? I have now 2 amps pumping 100w each so the sum should be 200w

then I insert an active crossover in all 3 channels and I separate HF from LF. I feed the separated frequencies to 6x100w individual channels, each connected to the binding posts (3 HF and 3 LF)

what has changed with respect to the second scenario?

Cmiller

Just bought a Pioneer Elite SC-25 and my Rti10 came to life!.."did not Bi-amp"

mdaudioguy

GrandeBoma wrote: »

still doesn't answer my question

let's say I buy a 3x200w amp and I hook it to my fronts and center's binding posts who have the jumper on (HF + LF)

then I change amp, and put a 6x100w but this time I remove the jumper, and feed 3x 100w in the HF and 3x in the LF. From pre-out I feed each signal (FR, FL and center) in a pair of amp in with a Y cable. What changes, from electromagnetism's standpoint? I have now 2 amps pumping 100w each so the sum should be 200w

then I insert an active crossover in all 3 channels and I separate HF from LF. I feed the separated frequencies to 6x100w individual channels, each connected to the binding posts (3 HF and 3 LF)

what has changed with respect to the second scenario?

Start a new thread, maybe?

mdaudioguy

Cmiller wrote: »

Just bought a Pioneer Elite SC-25 and my Rti10 came to life!.."did not Bi-amp"

Good for you! That's supposed to be a very nice receiver. Wouldn't mind getting my hands on one someday. Enjoy!

tonyb

GrandeBoma wrote: »

still doesn't answer my question

let's say I buy a 3x200w amp and I hook it to my fronts and center's binding posts who have the jumper on (HF + LF)

then I change amp, and put a 6x100w but this time I remove the jumper, and feed 3x 100w in the HF and 3x in the LF. From pre-out I feed each signal (FR, FL and center) in a pair of amp in with a Y cable. What changes, from electromagnetism's standpoint? I have now 2 amps pumping 100w each so the sum should be 200w

then I insert an active crossover in all 3 channels and I separate HF from LF. I feed the separated frequencies to 6x100w individual channels, each connected to the binding posts (3 HF and 3 LF)

what has changed with respect to the second scenario?

Again,just too many variables in your scenario. No matter how many times you split a signal, the amp is still only delivering x amount per channel. An active crossover means you removed the crossover in the speaker and I assume you would use an active one of better quality. Also, one amp delivering 6 channels of power is still sharing the same power supply and won't have the current of a good quality 2 channel amp. It's about the power supply,current, not watts. No 6 channel receiver has the current running in 6 channels as an amp in 2 channels. You could slice up the pie all you want from a watts stand point, but your missing the boat if you think it's about watts.

Cmiller

Just bought a SC-25 ,ive been reading about it,and look what i ran into about Bi-amping this AVR,i guess i need to try it out..Run 7 channels compared to 5

Ultimate AV Magazine

With five channels driven continuously into 8-ohm loads (blue curve), the amp reaches 0.1% distortion at 119.7 watts and 1% distortion at 153.9 watts. With seven channels driven continuously into 8-ohm loads (green curve), the amp reaches 0.1% distortion at 137.8 watts and 1% distortion at 149.0 watts. It's odd that the power output at 0.1% distortion with five channels driven is less than with seven channels driven, but that is indeed the case with this AVR. The test was performed several times to verify this result.

The manufacturer's stated distortion of 0.09 % was reached at 135.3 watts with seven channels driven into 8-ohm loads. This corresponds almost exactly with the specified power output.
http://www.ultimateavmag.com/avrecei...er/index7.html


forum link..http://www.avsforum.com/avs-vb/showthread.php?t=1170880&page=6

Tour2ma

ComfyC,
Sorry for taking so long and I'm still not done with my full post, so here's a sneak preview...

comfortablycurt wrote: »

So what happens to the 80% of the power that never reaches the tweeter? It goes to the woofer. What happens to the 20% of the power that never reaches the woofer? It goes to the tweeter.

You really need to think this through... think about the path available to the unused power in the "bi-amp" case. It is no longer directly available to the "other" driver as it is in the single-wire (w/ jumper) and bi-wire cases...

comfortablycurt wrote:

Take it or leave it. I'm not gonna keep arguing this point, since you seem pretty stuck on your opinion of it. Just one question...have you ever actually tried bi-amping with an AVR? Just a question.

AVR? No. Multi-ch Amp? Yes... Am I still discussion worthy? And to me it's a discussion, not an argument.

As for being stuck... nah... I've been testing my own opinion right along with everyone else. So far I've only become more certain that I'm right, but that could still change...

I understand your frustration, but I hope you hang just a bit longer... think just a bit more. Either way I've at least one more long post to make here...

gp4jesus

Cmiller wrote: »

All (5) channels driven 8-ohm loads, 0.1% distortion @ 119.7W; 1% distortion at 153.9W. All (7) channels driven 0.1% distortion @137.8W 1% distortion @ 149.0 watts. ...odd that the power output... ...w/5 channels driven is less than w/7channels driven.

Links seem broken. Impressive 8 ohm specs. BTW did you see any 4 ohm specs? The gross exception of 8 ohm speaker's impedence plots stay @ 8 ohms.

my $.02

tony

Cmiller

Taken from this..middle of the page..http://www.avsforum.com/avs-vb/showthread.php?t=1170880&page=6

gp4jesus

Cmiller wrote: »

Taken from this..middle of the page..http://www.avsforum.com/avs-vb/showthread.php?t=1170880&page=6

Hmmm... Took a few clicks to find it. Might be good for 25% more into 4ohms measured all the same as 8 ohm readings. I'd be reluctant to crank it w/most channels connected to 4 ohm speakers.

I wonder what we'd see RMS/peak "20hz-20Khz" @ 8 & 4 ohms.

another $.02 worth

tony

tonyb

If you notice, ice amps like those in the Pioneer SC series or their newer elite series don't tend to drop off a cliff running between 5 and 7 channels like regular AVR'S.

Cmiller

tonyb wrote: »

If you notice, ice amps like those in the Pioneer SC series or their newer elite series don't tend to drop off a cliff running between 5 and 7 channels like regular AVR'S.

Yep,thats why i bought it..:)

GrandeBoma

thanks for the explanation in private gp4jesus it is like I expected

gp4jesus

tonyb wrote: »

...ice amps like those in the Pioneer SC series or their newer elite series don't tend to drop off a cliff

ice amps??? Is this an abreviation? For what

GrandeBoma

gp4jesus wrote: »

ice amps??? Is this an abreviation? For what

ICE power is an acronymous for something I can't remember. it's a particular type of class D that has very high efficiency rates, something like 80%. For example, the european pioneer receiver lx-52 does not feature ice amplification, while the next model up, the lx-72 does. The former will use more electricity to output less watts than the latter

mdaudioguy

GrandeBoma wrote: »

ICE power is an acronymous for something I can't remember.

acronymous?

See here: http://www.icepower.bang-olufsen.com/

photocrazy

Coming to back to bass problem in Rti10s, it looks like my room is too big to get that punchy bass..lol

bmor

Photo, I've been playing with the equalizer a lot on the 1325 and seem to be able to get all the bass I want, and more, at least to my ears. I ran Auto MCACC but didn't like the results so had to manually adjust. This is all for two channel with no sub. Also connected a 2 x 150 wpc amp with no noticeable difference.

photocrazy

bmor wrote: »

Photo, I've been playing with the equalizer a lot on the 1325 and seem to be able to get all the bass I want, and more, at least to my ears. I ran Auto MCACC but didn't like the results so had to manually adjust. This is all for two channel with no sub. Also connected a 2 x 150 wpc amp with no noticeable difference.

what adjustments u made in EQ

bmor

Set 63hz at +5 then sloped it down in more or less equal steps to -3 at 2Khz then back up to +2.5 at 16Khz. I'm still fine tuning it but found this gave decent lows and suppressed some of the tinny sound. I've been using Peter Gabriel's Us cd ripped lossless on a memory stick plugged into the receiver and listening in direct mode.

Tour2ma

photocrazy wrote: »

Coming to back to bass problem in Rti10s, it looks like my room is too big to get that punchy bass..lol

Hey, I remember you... you're the guy that started this mess,,, :biggrin:

bmor,
Just bare in mind that your LF boosting has probably doubled the baseline power demands you've placed upon your amp...

Enjoy...

photocrazy

bmor wrote: »

Set 63hz at +5 then sloped it down in more or less equal steps to -3 at 2Khz then back up to +2.5 at 16Khz. I'm still fine tuning it but found this gave decent lows and suppressed some of the tinny sound. I've been using Peter Gabriel's Us cd ripped lossless on a memory stick plugged into the receiver and listening in direct mode.

This is more like a 'V' curve EQ for bass/treble heavy music. But do you see any muddiness in the bass ?

photocrazy

Tour2ma wrote: »

Hey, I remember you... you're the guy that started this mess,,, :biggrin:

bmor,
Just bare in mind that your LF boosting has probably doubled the baseline power demands you've placed upon your amp...

Enjoy...

Lol...yea...it was me..!! I found I could hear tight bass in the adjacent room, even though my speakers are in the living room. Am I doing anything wrong in the placement ?