Using a Receiver Without Preouts for Connection to an Amp?

[PearlcorderS701]

All Polk speakers are pretty efficient until you get to the LSi line. Which are a 4 ohm load.

Indeed; I was staying away from the LSi line based on those specs and my current gear, at least...

Yes they go to the low 30's. That's why I suggested in one of your other threads to run them full range. I still think you should try it. You won't hurt anything. You just might no have the dynamic headroom you get with the 60hz crossover. But none the less I think you might be surprised at what your 605 is capable of.

...I understand that, but this seems to be in direct opposition of what you're saying in the last couple of pages of this thread...you're saying crossing over the 12s will really allow this amp to come "more to life" and were even enthusiastic when I suggested they were crossed over at 60Hz...

I recall you saying I can try Full Range, being that my sub can't even hit these low notes (or can it?), but are you sure this wouldn't put a burden on the 605's meager power supply? Everything I read online suggests never running fronts on full range, no matter how "large" they really are...

That said, what are your thoughts on running/utilizing the Audyssey 2EQ system on the 605? I'm running the AVR with manual settings and calibration numbers, with the room EQ off -- should I run this AVR with the auto program and let it EQ the room?

 

[Mika75]

Yes they go to the low 30's. That's why I suggested in one of your other threads to run them full range. I still think you should try it. You won't hurt anything. You just might no have the dynamic headroom you get with the 60hz crossover. But none the less I think you might be surprised at what your 605 is capable of.

I agree, this will add much more dynamics, that sub just isn't capable alone.

 

[anamorphic96]

...I understand that, but this seems to be in direct opposition of what you're saying in the last couple of pages of this thread...you're saying crossing over the 12s will really allow this amp to come "more to life" and were even enthusiastic when I suggested they were crossed over at 60Hz...

No its not in opposition. All I have said is that when crossing things over higher you pick up some dynamic headroom. But the 12's are pretty efficient so running them full range is not a problem. Many people do this when they do not have a sub. Give it a shot. It's free and you have nothing to lose. If you find the amp is straining switch it back.

We have discussed Audyssey in the past. I use it and feel it does a good job at calibrating things. Especially at getting the sub distance and levels correct. It also accounts for the electronic delay in the sub and my sub eq. Which helps in getting a seamless blend.

 

[PearlcorderS701]

I agree, this will add much more dynamics, that sub just isn't capable alone.

...that's why I am crossing the 12's over at 60, so they can add some slam while also relieving a bit of the load from the 605's amp...

 

[PearlcorderS701]

No its not in opposition. All I have said is that when crossing things over higher you pick up some dynamic headroom. But the 12's are pretty efficient so running them full range is not a problem. Many people do this when they do not have a sub. Give it a shot. It's free and you have nothing to lose. If you find the amp is straining switch it back.

Okay; I, personally, felt that some of those sentiments and suggestions were in a bit of an opposing state...

We have discussed Audyssey in the past. I use it and feel it does a good job at calibrating things. Especially at getting the sub distance and levels correct. It also accounts for the electronic delay in the sub and my sub eq. Which helps in getting a seamless blend.

My 2EQ system in the 605 doesn't do sub EQ, that's why I wanted your opinion on running it with my AVR...

Funny that you mentioned getting your sub distance correct -- most people I have read about utilizing Audyssey either via Denon or Onkyo products seem to say that the sub distance is almost always wrong, in particular.

 

[anamorphic96]

Okay; I, personally, felt that some of those sentiments and suggestions were in a bit of an opposing state...



My 2EQ system in the 605 doesn't do sub EQ, that's why I wanted your opinion on running it with my AVR...

Funny that you mentioned getting your sub distance correct -- most people I have read about utilizing Audyssey either via Denon or Onkyo products seem to say that the sub distance is almost always wrong, in particular.

Well my sub is 10ft away but the receiver says 14ft. Because it's accounting for the electronic delay in the sub and my Velodyne SMS-1.

Most people don't bother to read the FAQ at Audyssey as well. Or even consult with them. I have and it helped me understand the system better.

 

[PearlcorderS701]

Well my sub is 10ft away but the receiver says 14ft. Because it's accounting for the electronic delay in the sub and my Velodyne SMS-1.

Most people don't bother to read the FAQ at Audyssey as well. Or even consult with them. I have and it helped me understand the system better.

I understand.

Now that we're getting closer to the roots and guts of this thread's intentions, let's go over some elements here...

First of all, I shouldn't consider any "ghetto rigging" aparatus for adding amps to my preout-less 605, right? Definitely look to replacing it with a more powerful and stable AVR, IF I go down that road...

Second, if I do NOT look into a new AVR right now, as you suggest to continue milking all the performance out of my 605, I should be looking at a new sub and center channel, correct?

Third...If I DO look into a new Onkyo AVR, I should be considering:

-NR 1007/1008
-NR 807/808

...yes?

 

[anamorphic96]

I understand.

Now that we're getting closer to the roots and guts of this thread's intentions, let's go over some elements here...

First of all, I shouldn't consider any "ghetto rigging" aparatus for adding amps to my preout-less 605, right? Definitely look to replacing it with a more powerful and stable AVR, IF I go down that road...

Second, if I do NOT look into a new AVR right now, as you suggest to continue milking all the performance out of my 605, I should be looking at a new sub and center channel, correct?

Third...If I DO look into a new Onkyo AVR, I should be considering:

-NR 1007/1008
-NR 807/808

...yes?

Yes on all of the above. But I would stay with the 1007 or 807 as you will get much better deals since there being closed out.

 

[PearlcorderS701]

Yes on all of the above. But I would stay with the 1007 or 807 as you will get much better deals since there being closed out.

Okay, Anamorphic...

Will the replacement 1008 or 808 have any substantial improvements?

I bought the RTi12s which were an "outdated" model for a good price, so perhaps I should just go this "outdated" route and do the same with the AVR...

 

[anamorphic96]

Okay, Anamorphic...

Will the replacement 1008 or 808 have any substantial improvements?

I bought the RTi12s which were an "outdated" model for a good price, so perhaps I should just go this "outdated" route and do the same with the AVR...

Unless you need the HDMI 1.4 3D capability get the 1007.

The 1008 is severe downgrade in the amp section. It loses 10lbs in weight as well it's Ultra certification. Not a good sign in my book. Granted its a little cheaper. It also loses the Audyssey MultEQxt system. Which is there best system outside of getting the pro version.

The 1007 is the receiver to get. It offers tremendous flexibility and a killer amp section and Audyssey MutEQxt. All for less than a thousand if your patient and wait for prices to drop.

The difference between the 808 and 807 is less. Mainly just the HDMI upgrade and some more networking features. The amp sections look to be the same.

But I'm going to say it again. The 1007 is the receiver to get and highly doubt you would ever need an amp upgrade. The thing weighs over 50lbs.

 

[Mika75]

But the 12's are pretty efficient so running them full range is not a problem. Many people do this when they do not have a sub. Give it a shot. It's free and you have nothing to lose. If you find the amp is straining switch it back.

PearlcorderS701 - Have u even tried this recommendation yet ??


RUN THE FRONTS FULL RANGE, DO NOT CROSS THEM OVER, NOW ADJUST THE SUB FREQUENCY ACCORDINGLY!
.

 

[PearlcorderS701]

What do you mean "adjust the sub crossover accordingly"...? If I'm not running a sub in the Full Range configuration you're suggesting, what crossover are you referring to -- the LPF of LFE setting in the AVR?

 

[PearlcorderS701]

Unless you need the HDMI 1.4 3D capability get the 1007.

Do you think 3D will take off? Worth buying into yet?

I will put the 1007 on my short list. MAYBE the 1008...

The 1008 is severe downgrade in the amp section. It loses 10lbs in weight as well it's Ultra certification. Not a good sign in my book. Granted its a little cheaper. It also loses the Audyssey MultEQxt system. Which is there best system outside of getting the pro version.

I see. Why did they come out with a replacement model that performs worse than the 1007? Or at least offers less...

Will the only differences be the HDMI 1.4 spec? How useful is the MultEQ XT in setting up a system for a room?

The 1007 is the receiver to get. It offers tremendous flexibility and a killer amp section and Audyssey MutEQxt. All for less than a thousand if your patient and wait for prices to drop.

The difference between the 808 and 807 is less. Mainly just the HDMI upgrade and some more networking features. The amp sections look to be the same.

But I'm going to say it again. The 1007 is the receiver to get and highly doubt you would ever need an amp upgrade. The thing weighs over 50lbs.

Okay. I'll try and look for prices on the 1007...

Thanks.

Any additional input or thoughts are welcome.

 

[TLS Guy]

What do you mean "adjust the sub crossover accordingly"...? If I'm not running a sub in the Full Range configuration you're suggesting, what crossover are you referring to -- the LPF of LFE setting in the AVR?

He means setting your mains full range. Speaker set up large for mains. Click sub yes. Then set crossover to sub on receiver to 2 X F3 of mans, which in your case will be about 50 Hz. I would start at 60 Hz and see what happens.

Your main speakers have a lower F3 than your sub as I pointed out to you once before. Therefore in your situation you are selling yourself short by crossing over your mains.

There is a prevalent myth that crossing over the mains to a sub, significantly off loads the receiver amps. For most speakers, and certainly not your Polks, (as Polk shared the impedance curve of your speakers with me,) the peaks of impedance associated with bass tuning kick in below the point of crossover, reduce the power from the receiver required at those frequencies. So for most speakers, especially ported ones, the power delivered to the speakers below 60 Hz is small.

The area where a lot of power is delivered to the speakers by the amp, is from the point of the start of diffraction compensation (usually around 600 Hz) to about 60 to 80 Hz.

So the bottom line is that not crossing your mains over and running them full range will insignificantly increase the power demands on your receiver.

Another factor that perpetuates the myth, is the belief that the sub frequencies take a lot of power. Not so. In fact when you look at an energy spectrum meter the energy in sub range is quite small. The myth comes about because people want small subs. Bass enclosures really want to be huge. The bottom line is that building small subs results in very poor sensitivity and efficiency, so that the actual sensitivity of a sub is usually 8 to 10 db lower than for the other speakers. Now for every 3 db loss of efficiency the power has to be doubled.

So a hundred watt receiver needs to be mated with a sub with a power of 400 to 800 watts given the usual relative sensitivities.

I have been over this a number of times and people don't seem to get it.

The power required to drive a sub is because to relative sensitivities of the speakers and not due to energy in the 20 to 80 Hz range.

 

[anamorphic96]

He means setting your mains full range. Speaker set up large for mains. Click sub yes. Then set crossover to sub on receiver to 2 X F3 of mans, which in your case will be about 50 Hz. I would start at 60 Hz and see what happens.

Your main speakers have a lower F3 than your sub as I pointed out to you once before. Therefore in your situation you are selling yourself short by crossing over your mains.

There is a prevalent myth that crossing over the mains to a sub, significantly off loads the receiver amps. For most speakers, and certainly not your Polks, (as Polk shared the impedance curve of your speakers with me,) the peaks of impedance associated with bass tuning kick in below the point of crossover, reduce the power from the receiver required at those frequencies. So for most speakers, especially ported ones, the power delivered to the speakers below 60 Hz is small.

The area where a lot of power is delivered to the speakers by the amp, is from the point of the start of diffraction compensation (usually around 600 Hz) to about 60 to 80 Hz.

So the bottom line is that not crossing your mains over and running them full range will insignificantly increase the power demands on your receiver.

Another factor that perpetuates the myth, is the belief that the sub frequencies take a lot of power. Not so. In fact when you look at an energy spectrum meter the energy in sub range is quite small. The myth comes about because people want small subs. Bass enclosures really want to be huge. The bottom line is that building small subs results in very poor sensitivity and efficiency, so that the actual sensitivity of a sub is usually 8 to 10 db lower than for the other speakers. Now for every 3 db loss of efficiency the power has to be doubled.

So a hundred watt receiver needs to be mated with a sub with a power of 400 to 800 watts given the usual relative sensitivities.

I have been over this a number of times and people don't seem to get it.

The power required to drive a sub is because to relative sensitivities of the speakers and not due to energy in the 20 to 80 Hz range.

I think I see where your going with this.

However in commercial cinemas, why do the sub amps tend to have 3 to 4 times the power of the main speakers ? Even though they tend to have the same sensitivity.

Why is it when companies rate receiver power and don't test using the full bandwidth does the power increase ? I have always been under the impression that the low end bass frequencies demand more power, as well some speakers do demand more at the higher frequencies depending on the impedance curve. But not quite to the same degree in all speakers.

What is the impedance curve like on the RTi12's. Are they a pretty efficient speaker as Polk has stated ? Or are they the power hog's everyone states ?

Thanks for the input. I always value your opinion.

 

[AVRat]

Pearl, do you feel like a dog chasing his tail, it sure seems like it? Anamorphic has had your back on this from the beginning and hasn’t ever steered you wrong! I completely understand your frugality, but taking shortcuts to achieve the proper end result doesn’t work. You’ve made some mistakes trying to put your system together and I think you’re realizing what it’ll take to set things right. I think everybody has you on the right track now and you need to try and not deviate from the end goal.

* The CSi 5/3 are the matching centers for this vintage RTi line.
* A sub like the SVS PB12-NSD to meet the $600 budget. Maybe add a second later on depending on room size.
* The Onkyo 1007 has the power to drive the 12s and features needed. A good alternative would be the 7/807 paired with an Emotiva XPA-3.

 

[tom67]

Anamorhic96 is being dispatched to your home with a system of our choosing here on the forum....further concerns are needless....

 

[TLS Guy]

I think I see where your going with this.

However in commercial cinemas, why do the sub amps tend to have 3 to 4 times the power of the main speakers ? Even though they tend to have the same sensitivity.

Why is it when companies rate receiver power and don't test using the full bandwidth does the power increase ? I have always been under the impression that the low end bass frequencies demand more power, as well some speakers do demand more at the higher frequencies depending on the impedance curve. But not quite to the same degree in all speakers.

What is the impedance curve like on the RTi12's. Are they a pretty efficient speaker as Polk has stated ? Or are they the power hog's everyone states ?

Thanks for the input. I always value your opinion.

You raise some interesting points.

First of all audio in large commercial spaces is a very different animal from domestic audio.

Loudspeakers may be problematic devices for the home , but for the large spaces they are a nightmare. That is why you so seldom hear good systems in large spaces.

The real problem is the coupling of the speaker and loading to the space. Sealed enclosures are hopeless and vented enclosures also couple poorly. TLs couple to an extent, but efficiency remains a problem. I have only had real success with huge back loaded horns the size of kiosks.

I'm totally unaware of any commercial system for large spaces that I would regard as true high fidelity speaker systems. I admit I set the bar high.

The only ones I have heard that have been any good have been highly customized systems by individuals that really know what they are doing.

My most successful system in a large space involved huge bass horns with 33 inch mouths, and huge tall linear arrays.

Bass horns really shine in large spaces, and you don't need a lot of power. They really couple to the space.

So I think commercial subs are fighting severe inefficiencies related to coupling to the space.

Cone loudspeakers do indeed become less efficient in the bass for a variety of reasons, so this has to be corrected for. This does consume a lot of amplifier power. However in tuned enclosures around resonance sensitivity increases greatly. Below tuning however, things fall apart quickly, but a speaker should never be driven at the point where the driver decouples from the enclosure.

Small cones are lighter and this is a big contributing factor to increased sensitivity.

To lower the fundamental resonance of a speaker, you have to make the cone heavier or the suspension softer, or a combination of both. However a very soft suspension requires sealed loading to prevent destruction. The rear cone radiation is totally lost and the rise in F3 from that form of loading has to be compensated, demanding enormous amp power.

Certainly in my system were the low bass system has a sensitivity of 93 db 1 watt 1 meter, and the pipes really couple with the room, the bass amps just coast. Despite that I can easily threaten the integrity of the room.

So the issue is not that bass reproduction requires enormous acoustic energy, the issue is the inefficiencies in producing that acoustic energy given the problems of cone drivers, especially if a small foot print is desired.

As far as the RTi12s, I have not heard them. However they break a number of Carter's rules for successful speaker design.

We have had a number of members complain that they seem bass shy, despite them having a very respectably low F3.

They do have a low impedance above tuning as you would expect from all those drivers. So yes, I can confirm they are a difficult load.

The real problem is that they are weak in the wind above bass tuning. I'm certain this is related to a crossover at 120 Hz, with suboptimal parts to boot.

A design like that really demands an active crossover.

Even with an active crossover, a crossover in that range is hard to integrate with a sub, as you will inevitably get crossovers far to close together in frequency. That is always a nightmare.

Any speaker weak in the wind around an above 100 Hz will always sound bass shy and lack authority in the bass.

From the data I saw, I would say those speakers in any HT set up should always be set to large, and the sub blended in probably around 60 Hz.

 

[anamorphic96]

Anamorhic96 is being dispatched to your home with a system of our choosing here on the forum....further concerns are needless....

I would if he was in Northern California. But I don't think he is.

I did suggest the RTi8 and CSi5. Which would have been cheaper and easier to drive system. But he really wanted the 12's. He did get a good deal on them though. It's just gonna require more money to get the best out of them.

In my opinion I think he is doing pretty good. He just over thinks things. If he gets the center and upgrades the sub he will notice a world of difference. Especially in overall dynamics and visceral impact.

Then pick up the receiver to round things out and hes good to go for many years to come.

Hopefully he can get some photos posted in the near future as well.

 

[anamorphic96]

You raise some interesting points.

First of all audio in large commercial spaces is a very different animal from domestic audio.

Loudspeakers may be problematic devices for the home , but for the large spaces they are a nightmare. That is why you so seldom hear good systems in large spaces.

The real problem is the coupling of the speaker and loading to the space. Sealed enclosures are hopeless and vented enclosures also couple poorly. TLs couple to an extent, but efficiency remains a problem. I have only had real success with huge back loaded horns the size of kiosks.

I'm totally unaware of any commercial system for large spaces that I would regard as true high fidelity speaker systems. I admit I set the bar high.

The only ones I have heard that have been any good have been highly customized systems by individuals that really know what they are doing.

My most successful system in a large space involved huge bass horns with 33 inch mouths, and huge tall linear arrays.

Bass horns really shine in large spaces, and you don't need a lot of power. They really couple to the space.

So I think commercial subs are fighting severe inefficiencies related to coupling to the space.

Cone loudspeakers do indeed become less efficient in the bass for a variety of reasons, so this has to be corrected for. This does consume a lot of amplifier power. However in tuned enclosures around resonance sensitivity increases greatly. Below tuning however, things fall apart quickly, but a speaker should never be driven at the point where the driver decouples from the enclosure.

Small cones are lighter and this is a big contributing factor to increased sensitivity.

To lower the fundamental resonance of a speaker, you have to make the cone heavier or the suspension softer, or a combination of both. However a very soft suspension requires sealed loading to prevent destruction. The rear cone radiation is totally lost and the rise in F3 from that form of loading has to be compensated, demanding enormous amp power.

Certainly in my system were the low bass system has a sensitivity of 93 db 1 watt 1 meter, and the pipes really couple with the room, the bass amps just coast. Despite that I can easily threaten the integrity of the room.

So the issue is not that bass reproduction requires enormous acoustic energy, the issue is the inefficiencies in producing that acoustic energy given the problems of cone drivers, especially if a small foot print is desired.

As far as the RTi12s, I have not heard them. However they break a number of Carter's rules for successful speaker design.

We have had a number of members complain that they seem bass shy, despite them having a very respectably low F3.

They do have a low impedance above tuning as you would expect from all those drivers. So yes, I can confirm they are a difficult load.

The real problem is that they are weak in the wind above bass tuning. I'm certain this is related to a crossover at 120 Hz, with suboptimal parts to boot.

A design like that really demands an active crossover.

Even with an active crossover, a crossover in that range is hard to integrate with a sub, as you will inevitably get crossovers far to close together in frequency. That is always a nightmare.

Any speaker weak in the wind around an above 100 Hz will always sound bass shy and lack authority in the bass.

From the data I saw, I would say those speakers in any HT set up should always be set to large, and the sub blended in probably around 60 Hz.

They do have a low impedance above tuning as you would expect from all those drivers. So yes, I can confirm they are a difficult load.

Probably why many people have benefited from a well designed external amp. I think he will be ok with one of the THX Ultra certified receivers from Onkyo or other comanies. The amps are pretty stout and more than capable of driving 4 ohm loads.

From the data I saw, I would say those speakers in any HT set up should always be set to large, and the sub blended in probably around 60 Hz.

Probably worth trying after he steps into higher end receiver. Or possibly going with a 40hz crossover. I have heard systems crossed at 120,80,60,and 40 as well as full range mains running without a sub sound unbelievable, as long as they where calibrated properly.