RTi A9 Speakers Biamped

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climber07

Audiophyte
I am looking at purchasing the Polk Audio RTi A9 floorstanding speakers and driving them with the Onkyo TX-NR3009 AVR biamped. The receiver is rated at 140W 2 channels driven and I was hoping to get much better performance and clarity (especially with the bass) with the biamp setup. I listened to the speakers on the receiver (single amp driven) at Frys and was not very impressed with the speakers.

If I biamp these babies, will I get the punch and clarity I'm looking for (at least more than with one channel driving them)? Really need some guidance.
:confused:
 
GranteedEV

GranteedEV

Audioholic Ninja
The receiver is rated at 140W 2 channels driven and I was hoping to get much better performance and clarity (especially with the bass) with the biamp setup.
You won't.

I listened to the speakers on the receiver (single amp driven) at Frys and was not very impressed with the speakers.
Then you don't like the speakers. Passive Bi-amping won't change a thing.

If I biamp these babies, will I get the punch and clarity I'm looking for (at least more than with one channel driving them)?
There is a 98% chance that you will not. I leave the other 2% just in case you delude yourself into thinking you did.
 
zieglj01

zieglj01

Audioholic Spartan
I listened to the speakers on the receiver (single amp driven) at Frys and was not very impressed with the speakers.

If I biamp these babies, will I get the punch and clarity I'm looking for (at least more than with one channel driving them)? Really need some guidance.
:confused:
Forget it, if you are lucky - you will get 0.05% difference. Time to
look at KEF and Focal for starters, and find room in the budget for
a sub.
 
C

climber07

Audiophyte
I was actually considering active bi amping (two separate amplifier channels to each speaker). Passive bi amping is just four wires from the same amp, correct?

To clarify my "not very impressed" statement: the speakers sound really good. The clarity was incredible and the sound image was surprisingly wide and full.

I was shocked at the lack of power as they were being driven by a single 135W channel on each speaker (the size of the room could have a part in it too). I am going to have to set up an appointment with the showroom and he will set up the speakers with the active bi amp configuration with the Onkyo NR3009. I am hoping a dedicated amplifier channel to the highs and another to the three 7" subs will improve bass performance. I'm not sure, but I think the Onkyo performs the crossover function to the bi amped outputs internally before the amplifier circuit.

I have a 12" 250W JBL powered subwoofer for the foundation jarring lows... LOL
 
j_garcia

j_garcia

Audioholic Jedi
Active biamping would mean bypassing the passive crossover and using an external crossover and separate amps, not your receiver. Biamping with your receiver is practically the same as biwiring.

I have yet to see a receiver that is able to perform the crossover function for the speaker in a biamp configuration, and this would be obvious because it would have to be variable to accommodate virtually any bi-ampable speaker.

I have a 12" 250W JBL powered subwoofer for the foundation jarring lows... LOL
Are you saying that is inadequate? I'd probably spend some money on a new sub instead of biamping the mains.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I am looking at purchasing the Polk Audio RTi A9 floorstanding speakers and driving them with the Onkyo TX-NR3009 AVR biamped. The receiver is rated at 140W 2 channels driven and I was hoping to get much better performance and clarity (especially with the bass) with the biamp setup. I listened to the speakers on the receiver (single amp driven) at Frys and was not very impressed with the speakers.

If I biamp these babies, will I get the punch and clarity I'm looking for (at least more than with one channel driving them)? Really need some guidance.
:confused:
No because you are passive biamping. The speakers crossover is still there.

I think when you biamp those speakers, the HF amp just connects to the tweeter and not the mids and tweeter which would have little merit. The manual just says the high frequency amp just connect to the Hi-frequency section and I take that to mean the tweeter which is useless.

Now those speakers might be improved and removed the crossovers and then tiamped with active crossover using mini DSP and REW to equalize them, but I would not bank on it.

The real problem is that a full range speaker like that is really problematic. A passive crossover at 120 Hz shoots you right in the foot before you start.

A truly powerful full range speaker is a formidable undertaking and really does require active electronic crossovers for at least the lower transitions.

No one can provide a speaker with a frequency range like that of any quality for $1500 a pair

When all is said and done it is really not necessary with good subs.

Now I know it seems counter intuitive, but if you were to purchase these small bookshelves on appropriate stands, you would be far further ahead than with the Polks.

All you really need is a good powerful speaker that has a -3db point at 80 Hz. Preferably a sealed design, then when you cross to a good sub at 80 Hz you have a perfect crossover.

The only draw back is that they are not highly efficient and you would need a more power than a receiver would give.

I know these speakers well. They are clean and detailed and you really can drive them hard and get 103 db spl. Billy Woodman the designer of the speaker and drivers is the master of producing small drivers that can produce high spl without stress or burn out, with the use of high precision engineering.

Two of them are $1000 which is enough to allow you to buy a third speaker for the center, or put the savings to an external amp in the 250 to 300 watt per channel class.

The response of those speakers is perfect for an HT THX system.

I guarantee you would have none of the problems you so dislike with the Polks.
 
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climber07

Audiophyte
I appreciate your advice and guidance everyone. I now realize that by asking my question, I am in over my head. I spoke with a good friend of mine on the phone today and he spoke at length about preamps, class A tube amps for the highs, active crossovers, a good class D for the sub... I don't even know which way to turn now. I hear good things from people about the Polks, then I hear that you can easily buy better speakers in a smaller package for less money... Wow!

Thanks again guys.
 
TLS Guy

TLS Guy

Seriously, I have no life.
I appreciate your advice and guidance everyone. I now realize that by asking my question, I am in over my head. I spoke with a good friend of mine on the phone today and he spoke at length about preamps, class A tube amps for the highs, active crossovers, a good class D for the sub... I don't even know which way to turn now. I hear good things from people about the Polks, then I hear that you can easily buy better speakers in a smaller package for less money... Wow!

Thanks again guys.
There is always someone who likes every speaker no matter how awful. Lets just say you have a good ear, and your assessment of the Polks was on the money.

Now forget tubes and the audiophools, and keep it simple since you seem to be starting out.

Now if you have a good sub and speakers like I mentioned, then you really have an active speaker apart from the mid/woofer transition. It is low frequency crossover points where passive crossovers run onto the rocks.

Now THX recommend a speaker with a cut off around 80 Hz falling at 12 db per octave. That essentially means sealed as good TLs are far and few between and will likely be beyond your budget.

Now ported enclosures taper at 24 db per octave. How does this matter? Well, on your receiver or pre pro the device will cut your sub out at 24 db per octave above where you set the crossover, this is called the low pass filter and in this case fourth order. Now it will cut your main speakers at 12 db per octave above where you set the crossover. This is the high pass filter and in this instance is a second order one. But you have 12 db acoustic roll off from the speaker if it is sealed. So two 12db per octave (second order) summed adds up to a 24 db per octave filter (Fourth order).

So we now have fourth order low and high pass filters, and it is symmetrical, which is desirable.

That is why THX recommend sealed speakers with a point at which they are 3db down in the neighborhood of 80 Hz for a THX system.

The problem is this usually describes a bookshelf type system and few can achieve satisfactory sound pressure levels.

The ATC SCM 7 can achieve very good spl. granted with fairly hefty amplification in rooms that are not unduly over sized.

The other benefit is very high wife acceptance factor.

I admit the SCM 7 is not well known here, but in the UK it has been showered with awards.

I know the speaker well and it is crystal clear and at least as good as any planar in this regard, and its imaging is excellent.

The nice thing about the SCM 7 is that is small enough that you can use it for mains, center and surrounds.

In my view it would be best to match those speakers with a sealed sub and preferably 2.
 
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climber07

Audiophyte
WOW! Went back to the showroom and they hooked up the RTi A9s to the Onkyo NR3009 biamped. Because the speakers are so power hungry, they sang like an eagle with the two inputs. The highs obviously didn't have any noticeable change, but the bass was much cleaner and more powerful. There was much more headroom as well. with a single input per channel, the receiver had to be set all the way up to reference. With biamp, they receiver was able to be set 10-15 db less and still have a higher SPL.

For the price, I think they are the ones. I've been all over since my original post and have listened to everything from Martin Logan electrostats, to KEF, to Monitor Audio across everything from 25 year old tube amps to brand new solid state amps. Most of the speaker setups I really liked cost four times as much or more. I have to find a happy medium, especially with the bosses approval factor in mind. If she's not happy, I won't be either... LOL

I will hold off on an Emotiva XPA-2 for a while. I'm sure 300W per channel will make them perform even better.
 
fuzz092888

fuzz092888

Audioholic Warlord
Congrats good to hear you found something you liked, and that satisfies the boss ;)

I'm not surprised they sounded better bi-amped. I've read that many times before about those speakers. Those woofers tend to need tons of power, and even though you're going to hold off on the amp for now, I think you'd be most happy with somewhere in the 300 WPC area.

I was looking at these speakers too and I can tell you that more power definitely helps them.
 
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climber07

Audiophyte
I think 300 wpc will be a sweet spot. I've heard a lot of people with these speakers say the XPA-1 is nirvana. I don't think I can afford to buy two 500W monoblock amps and post bail at the same time when the cops show up for the 20th time...
 
F

fokakis1

Audioholic Intern
Congrats. I hope you enjoy them. The bass is strong, but they need a few weeks of breaking in before they really start to slam.
 
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climber07

Audiophyte
I am still on the fence regarding the CSI A6 center and the FXI A6 surrounds. They are a big change from my Bose Lifestyle system. The Bose speakers are small and sexy, but lack the quality. I guess that's what you get for two inch drivers... LOL

Anyway, the A9s are definitely going to be an upgrade. Especially when I upgrade them to the XPA-2...
 
fuzz092888

fuzz092888

Audioholic Warlord
I don't know about the surrounds. My suggestion is that you could get a cheaper surround that would handle whatever you want to put through it movie wise. Unless you're playing multichannel stereo music, then some cheaper surrounds would work just fine.

I have the A6 myself and have owned it for a little over a year now. I like it, and it performs admirably. I have no actual complaints about it and if you have the space it will match nicely with the A9s. It will timbre match and go with your overall setup well.

Personally I'm going to look to replace mine, only because I want a center with a ribbon or RAAL tweeter to go with my new tower speakers :D
 
agarwalro

agarwalro

Audioholic Ninja
but they need a few weeks of breaking in before they really start to slam.
Speaker break in and cables/electronics burn in are myths best left in the realm of dragons and wizards.

In reality what is happening is, your ears get accustomed to the sound of the speakers, so different program material sounds better over time.
 
jinjuku

jinjuku

Moderator
Speaker break in and cables/electronics burn in are myths best left in the realm of dragons and wizards.

In reality what is happening is, your ears get accustomed to the sound of the speakers, so different program material sounds better over time.
A lot of DIY designers will let the speaker break in for a while before taking measurements BTW. It's not on the magnitude of weeks or months however. And EVERYONE if they listen to their system for any decent amount of time has 'burned in' all their components just by use.

Yes the notion of 'purposeful break/burn in' is rather absurd. Just enjoy.
 
agarwalro

agarwalro

Audioholic Ninja
A lot of DIY designers will let the speaker break in for a while before taking measurements BTW. It's not on the magnitude of weeks or months however.
I concede for this specific example, buying raw drivers directly from manufacturer, break in is needed. I have even seen the manufacturers specify break in directions themselves.

For the example to which I responded, breaking in the Polk speaker (or any store bought speaker) and seeing a sound quality improvement over time, it is pure hogwash.
 
jinjuku

jinjuku

Moderator
I concede for this specific example, buying raw drivers directly from manufacturer, break in is needed. I have even seen the manufacturers specify break in directions themselves.

For the example to which I responded, breaking in the Polk speaker (or any store bought speaker) and seeing a sound quality improvement over time, it is pure hogwash.
The point is entirely academic on either side of the debate. You listen to your speakers long enough and they are all 'broken in'. It's an amazing non-argument that gets, well, a lot of argument:D

My tack is to point out the rather obvious.
 
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climber07

Audiophyte
Honestly, I think most of us are over 30 - 35 anyway. At that age, most (if not all) of us loose quite a bit of our hearing (specific freq wise). I know I have lost my 15K and above as I get a hearing test annually in the Marine Corps. They said I have excellent hearing for my age, but what does that friggin mean... LOL

Being an electronics technician and understanding amplifiers and radio frequency and above radio systems, I do know that speaker wire break in is B.S. I can see how the foam around a driver could become more subtle over a period of use. As for the cones, they shouldn't change much. The coils, won't change.

I think that any good EQ will fix the sonic peculiarities of most decent quality speakers.

Now to find some really well recorded music... Most of the music I like was recorded with tin cans and wire (classic rock). LMAO!
 
P

PENG

Audioholic Slumlord
Now to find some really well recorded music... Most of the music I like was recorded with tin cans and wire (classic rock). LMAO!
Good point, the quality of the recordings is often a more important factor than the electronics (media players, amplifiers, preamps etc.). I felt so strong about it that I started a thread to collect feedbacks from others on well recorded discs and/or flac/wave files for all kinds of music.
 
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