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dhornick
12-18-2007, 08:17 AM
OK, same old question. Polk suggests that you wire their subwoofers through the front speakers. I realize it’s their product so they can suggest anything they think is right and that it might be a good suggestion. However is it really necessary? I mean is there an exact, precise, unequivocal notice to the human ear. Or, is it like the difference between a Pentium 3 chip and a Pentium 4 chip in the computer world of processing? Yes, it’s faster but not to the point where the naked human eye can see the difference.

obieone
12-18-2007, 06:49 PM
IMO. YES! I experimented with my new speakers (T90's)by running the fronts direct from the recvr, and sub out. I then set the LFE-norm to LFE+MAIN on my recevr. which gives the same effect as running the fronts thru the sub.
BUT, this too has a drawback- it only works on multi channel signal(dolby, dts).
So the question is, If you're going to listen to ONLY multi-ch. sources, then don't bother running the fronts thru the sub(set LFE TO LFE+MAIN).
But if you want to listen to regular cd's, along with multi ch., then run the fronts thru sub, set fr. L/R to large and sub to 'off'/'no'
good luck

CamaroSS
12-19-2007, 12:08 AM
Here's a question...if you run front speakers through the sub do you lose true 5.1 dolby processing? only my center speaker can be changed fron nominal to large on my kenwood 6 channel receiver. all other settings are done through db and distance adjustments. i still haven't figured all settings yet and my RM6880 system sub must be turned almost all the way up to get good bass response. also has rev & normal switch on sub...what does that pertain to? right now i am running fronts through sub via wires as there is no LFE port. local tv channels (from direct tv signal) send low garbled audio through all speakers except center. DVD signals seem fine. any suggestions?

seeclear
12-19-2007, 01:46 AM
Another question--when you wire the fronts through the L & R speaker connections on a powered sub, are you bypassing the amp in the sub and making your receiver power the sub? Seems like that might cause the receiver to work harder, whereas using the LFE line level output to the sub would allow the amp in the sub to take that stress off of the receiver. Somebody tell me what's what with that logic. TIA

dhornick
12-19-2007, 08:46 AM
Here's a question...if you run front speakers through the sub do you lose true 5.1 dolby processing? only my center speaker can be changed fron nominal to large on my kenwood 6 channel receiver. all other settings are done through db and distance adjustments. i still haven't figured all settings yet and my RM6880 system sub must be turned almost all the way up to get good bass response. also has rev & normal switch on sub...what does that pertain to? right now i am running fronts through sub via wires as there is no LFE port. local tv channels (from direct tv signal) send low garbled audio through all speakers except center. DVD signals seem fine. any suggestions?


Great question. I would like to know the answer to this as well.

dhornick
12-19-2007, 08:48 AM
Another question--when you wire the fronts through the L & R speaker connections on a powered sub, are you bypassing the amp in the sub and making your receiver power the sub? Seems like that might cause the receiver to work harder, whereas using the LFE line level output to the sub would allow the amp in the sub to take that stress off of the receiver. Somebody tell me what's what with that logic. TIA

Same here, another great question. Are there any Polk reps on here that monitor these forums?

tcrossma
12-19-2007, 09:41 AM
Another question--when you wire the fronts through the L & R speaker connections on a powered sub, are you bypassing the amp in the sub and making your receiver power the sub? Seems like that might cause the receiver to work harder, whereas using the LFE line level output to the sub would allow the amp in the sub to take that stress off of the receiver. Somebody tell me what's what with that logic. TIA

Connecting the speakers through the subwoofer does not cause the receiver/amp to power the sub. All it does is allow the sub to control the crossover point in a way that might possibly allow for a more seamless blend between your speakers and the sub.

Additionally, because you'll have set your speakers to Large all output will find its way to the subwoofer. The subwoofer can then determine what should be sent to the speakers and what should be sent to the sub in an optimal manner.

If you go the other route and use the sub pre-out on the receiver (which is the way I do it incidentally) then you have to make sure you've configured the receiver so that the signals are going to the right place. This involves setting a good crossover point, setting the speaker sizes correctly, and making sure that the "modes" you operate in send signals to where you want them to. For example, on my Yahama receiver the "stereo" mode sends data to the front L/R PLUS the sub pre-out. In "straight" mode I get only the front L/R and the sub only gets used for the LFE signal.

I don't think there's really a true right or wrong way to connect the sub, but the "polk way" has the benefit of being less reliant on the electronics of the receiver and is probably a little easier to ensure good sound. It's also the only way on some systems that either don't have a sub pre-out or that don't make use of the pre-out in certain modes.

dhornick
12-19-2007, 12:32 PM
Connecting the speakers through the subwoofer does not cause the receiver/amp to power the sub. All it does is allow the sub to control the crossover point in a way that might possibly allow for a more seamless blend between your speakers and the sub.

Additionally, because you'll have set your speakers to Large all output will find its way to the subwoofer. The subwoofer can then determine what should be sent to the speakers and what should be sent to the sub in an optimal manner.

If you go the other route and use the sub pre-out on the receiver (which is the way I do it incidentally) then you have to make sure you've configured the receiver so that the signals are going to the right place. This involves setting a good crossover point, setting the speaker sizes correctly, and making sure that the "modes" you operate in send signals to where you want them to. For example, on my Yahama receiver the "stereo" mode sends data to the front L/R PLUS the sub pre-out. In "straight" mode I get only the front L/R and the sub only gets used for the LFE signal.

I don't think there's really a true right or wrong way to connect the sub, but the "polk way" has the benefit of being less reliant on the electronics of the receiver and is probably a little easier to ensure good sound. It's also the only way on some systems that either don't have a sub pre-out or that don't make use of the pre-out in certain modes.

Agreed. If there is no Pre Out or LFE on said amp or sub there would ne question. You would have to use the "Polk Way".

psb962
12-19-2007, 09:00 PM
I ended up going the 'Polk Way' even though I have an LFE out. I found it very easy to match the sub output (volume and crossover) to the rest of the system.

All you have to do is play full bandwidth pink noise on all channels and adjust the sub vol and crossover until it sounds nicely blended in. No better way than turning an analog dial!

dhornick
12-20-2007, 09:16 AM
I ended up going the 'Polk Way' even though I have an LFE out. I found it very easy to match the sub output (volume and crossover) to the rest of the system.

All you have to do is play full bandwidth pink noise on all channels and adjust the sub vol and crossover until it sounds nicely blended in. No better way than turning an analog dial!


Let me ask this, when doing it the "Polk Way" does the AV Receiver control the volume of the sub as well? Meaning will my remote now control the volume of the sub?

tcrossma
12-20-2007, 09:33 AM
Let me ask this, when doing it the "Polk Way" does the AV Receiver control the volume of the sub as well? Meaning will my remote now control the volume of the sub?

You'll set the volume knob on your sub to something that blends in with your system. This will be done once as part of your calibration. Once that's done, the volume on the receiver will control both the output level of your speakers and the sub.

Ricardo
12-20-2007, 09:41 AM
You'll set the volume knob on your sub to something that blends in with your system. This will be done once as part of your calibration. Once that's done, the volume on the receiver will control both the output level of your speakers and the sub.

Which is not different if you use the LFE output to the sub.

dhornick
12-20-2007, 11:36 AM
Great thanks guys.

Erik Tracy
12-21-2007, 03:44 PM
I'm going to give the "Polk Way" a whirl this weekend.

Here's why...

I have a Yamaha 1800 AVR which works great - has all the features I want, sounds great for 5.1 Surround DVDs etc. And it has a nice feature called "Pure Direct" which cuts out all DSP except for 2-channel stereo to the L/R outputs.

The problem with this is that I have the sub out from the AVR to the LFE input on the sub - and when I switch to "Pure Direct" (mostly for snobbish cognac sipping 'old school' serious vinyl music listening ;) ) - BUT "Pure Direct" kills any output to the sub!

To get around this, I'm going to connect the AVR L/R mains to both my RTI4 mains and the PSW303 - the "Polk Way" - then set the AVR to have Large setting for the speakers with NO sub.

This will replicate my old configuration with a separate pre and power amp with no bass management which I had dialed in to give really nice sound.

And it will still allow me to enjoy the 5.1 Surround (LFE et al) effects for DVD movies.

Erik

CamaroSS
12-26-2007, 12:38 AM
dhornick....buddy, i am a newbie and have posted on a couple of questions and still have not gotten any answers to my questions that can help me. just about ready to return RM6880 system & go back to original kenwood that i knew how to adjust. maybe i'm a low budget guy, but i was talked out of the Bose series 10 for Polk by store representative. Not sure what to do as i had great sound before and not not sure where i'm at 'cause i don't really know how to set this system up using my kenwood 6 channel receiver. times running out & tired of guessing.

dhornick
12-26-2007, 09:11 AM
dhornick....buddy, i am a newbie and have posted on a couple of questions and still have not gotten any answers to my questions that can help me. just about ready to return RM6880 system & go back to original kenwood that i knew how to adjust. maybe i'm a low budget guy, but i was talked out of the Bose series 10 for Polk by store representative. Not sure what to do as i had great sound before and not not sure where i'm at 'cause i don't really know how to set this system up using my kenwood 6 channel receiver. times running out & tired of guessing.


CamaroSS, I'm as much of a newbie as you are with the exception that I've had my Polk surround speakers (5.1) for 7 or 8 years. The only things new I have are a brand new Sony Receiver and the Polk PSW404 sub. I have always been happy with my Polk speakers and the new Sony Receiver drives them pretty well. Now, getting the sub adjusted was by far the hardest part and actually I think I still have a little more tweeking to do but last night I played a couple of HD DVD disks from the Planet Earth BBC series and man oh man did it sound GREAT. I think I finally just about have it right. Have you ever looked at or joined the AVS Forums? http://www.avsforum.com that's actually where I get the most help. Good Luck.

obieone
12-26-2007, 09:12 AM
dhornick....buddy, i am a newbie and have posted on a couple of questions and still have not gotten any answers to my questions that can help me. just about ready to return RM6880 system & go back to original kenwood that i knew how to adjust. maybe i'm a low budget guy, but i was talked out of the Bose series 10 for Polk by store representative. Not sure what to do as i had great sound before and not not sure where i'm at 'cause i don't really know how to set this system up using my kenwood 6 channel receiver. times running out & tired of guessing.
Sorry for not answering your concerns.:(
1. You don't lose anything of the 5.1 wiring the "polk way", but you gain the sub playing 2 ch. sources-i.e. cd's
2. the 'rev./ norm' switch on the the sub has to do with electrical phasing- try flipping it and see if you have improvement
3. I don't know WHY your center channel would be the only speaker that you can designate as large?
4. please repost with the Kenwood model # and we may be able to help you

FerdyBoy
12-26-2007, 11:13 AM
Here's a question that I haven't seen answered---

Using the sub out connection to sub and wiring front L & R speakers to AVR's out--what effect does setting the fronts to "Large" have on signal frequency outputs to sub and fronts? Does this take away any LFE signal to the sub? I have R30's for front L & R and they could handle some of the lower frequencies. If you had this setup, where would you set your crossover point? I can go down to 100 htz from my AVR to the fronts. Or, would it be better to set them to small?

Thanks

CamaroSS
12-27-2007, 01:00 AM
obieone....thanks for the response. I have hooked up the RM6880 speaker system to a Kenwood VR-606 audio/video surround receiver. The original speakers had powered subwoofer w/ volume control running off the designated LFE RCA port on back of the 606. I have found that the center speaker & surround speakers can be set to either "off-nmnl-large" outputs. Front speakers do not have this option. (maybe they are included in the surround speakers?) All speakers can be individually adjusted by db & distance through a settings mode that isolates each speaker for adjustment. The Kenwood speakers sounded great and easy to adjust to different settings, but it was necessary to get speakers that were smaller & wall mountable. I chose Polk over Bose. Anyway the adjusting of front speaker outputs affects my sub input as I am using the "Polk way" wiring. The 606 sub LFE is in "off". Surround is in "large" & center speaker is in "nmnl" mode. Rev/normal switch on sub appears to have no change in sound chara cteristics that I can tell. This system has mode options for pro-logic, Dolby digital, cinematic equalization, Pli-music, Pli-movie....and so on. Room is approx 16x13 leaving rear speakers close to the couch. Most listening is to TV and DVDs. Any suggestions?

Sevenpointone
12-27-2007, 05:44 AM
Wiring your front left and right thru the sub, set your L/R speakers on large or you will lose sub info.
Wiring by this method you will not lose any channel of a 5.1, 6.1, or 7.1 Dolby setup. But you will not be in Dolby specs for equalization by doing this.You may not care either.
Under standard wire schemes, the small setting should only be used for speakers that cannot handle 80 Hz and below. The 40 Hz explosions are going to resonate the woofer and distort anything it produces. If you L/R woofers are smaller than 6 1/2 to 7 inches, you may want to explore the small setting and generally raise your sub to cross at 120 to compensate for the loss.
Setting to small or large has no effect on LFE. Only on LCRLsRs speakers that have the setting on your amp. 80,100 20 settings affect the sub.
Most modern receivers can output subs in two channel mode. Dig deep into the options menu.
7.1

Erik Tracy
12-27-2007, 01:00 PM
Connecting the speakers through the subwoofer does not cause the receiver/amp to power the sub. All it does is allow the sub to control the crossover point in a way that might possibly allow for a more seamless blend between your speakers and the sub.

Additionally, because you'll have set your speakers to Large all output will find its way to the subwoofer. The subwoofer can then determine what should be sent to the speakers and what should be sent to the sub in an optimal manner.

If you go the other route and use the sub pre-out on the receiver (which is the way I do it incidentally) then you have to make sure you've configured the receiver so that the signals are going to the right place. This involves setting a good crossover point, setting the speaker sizes correctly, and making sure that the "modes" you operate in send signals to where you want them to. For example, on my Yahama receiver the "stereo" mode sends data to the front L/R PLUS the sub pre-out. In "straight" mode I get only the front L/R and the sub only gets used for the LFE signal.

I don't think there's really a true right or wrong way to connect the sub, but the "polk way" has the benefit of being less reliant on the electronics of the receiver and is probably a little easier to ensure good sound. It's also the only way on some systems that either don't have a sub pre-out or that don't make use of the pre-out in certain modes.

I don't know if this is entirely correct or not.

My understanding and personal experimentation has been that if you directly connect the sub (in my case a Polk PSW303) from the L/R main outs from the amp (in my case a Yamaha RX-V1800 AVR) with fronts set to large (RTI4s for me) and No sub then:
* all LFE and other low bass signals get sent to both the RTI4s and the sub
* the volume control on the sub effects how much *more* the line level output from the AVR gets amplified *relative* to the fronts. If you increase the volume on the AVR then the sub does get louder as well because the line level signal is being increased and the internal sub amp amplifies it that much more.
* the cross over on the sub does NOT effect the signal content going to the L/R fronts - it is only a low pass to the sub - what I hear through the RTI4s does not change if I fully sweep the crossover knob on the back of the PSW303.

As others have stated wiring a sub using the sub out from your AVR to the LFE input is fine for most circumstances when you are listening to mult-channel sources.

However, if your AVR has a bypass mode for 2-channel listening only that defeats all the fancy DSP modes, then if you have your sub connected up via the LFE/RCA sub out then you get *nothing* from your sub (I verified this in my own personal setup when I set my AVR to "pure direct" mode for 2-channel stereo listening).

If that is not important then use the LFE/Sub out from the AVR.

If you want to use the bypass mode on your AVR (if it has one) for 2-channel stereo listening and you want to use your sub, then you should use the "Polk Way" - I do.

For me this works 'best' and provides the best sound and control of the sound - and I still get all the LFE 'thrills' when listening to multichannel DVDs (because I've got the L/R fronts set to large with NO sub).

FWIW,
Erik

tcrossma
12-27-2007, 01:10 PM
I don't know if this is entirely correct or not.

My understanding and personal experimentation has been that if you directly connect the sub (in my case a Polk PSW303) from the L/R main outs from the amp (in my case a Yamaha RX-V1800 AVR) with fronts set to large (RTI4s for me) and No sub then:
* all LFE and other low bass signals get sent to both the RTI4s and the sub
* the volume control on the sub effects how much *more* the line level output from the AVR gets amplified *relative* to the fronts. If you increase the volume on the AVR then the sub does get louder as well because the line level signal is being increased and the internal sub amp amplifies it that much more.
* the cross over on the sub does NOT effect the signal content going to the L/R fronts - it is only a low pass to the sub - what I hear through the RTI4s does not change if I fully sweep the crossover knob on the back of the PSW303.


The low-pass only filter nature of the sub's crossover was just recently discussed in another thread. I stand corrected on that point.

Erik Tracy
12-27-2007, 04:06 PM
The low-pass only filter nature of the sub's crossover was just recently discussed in another thread. I stand corrected on that point.

No biggy - not out to poke anyone in the eye :)

Ultimately it comes down to trying and deciding what works best for your own setup.

I'm very happy with mine - for now....

Erik

obieone
12-27-2007, 05:42 PM
obieone....thanks for the response. I have hooked up the RM6880 speaker system to a Kenwood VR-606 audio/video surround receiver. The original speakers had powered subwoofer w/ volume control running off the designated LFE RCA port on back of the 606. I have found that the center speaker & surround speakers can be set to either "off-nmnl-large" outputs. Front speakers do not have this option. (maybe they are included in the surround speakers?) All speakers can be individually adjusted by db & distance through a settings mode that isolates each speaker for adjustment. The Kenwood speakers sounded great and easy to adjust to different settings, but it was necessary to get speakers that were smaller & wall mountable. I chose Polk over Bose. Anyway the adjusting of front speaker outputs affects my sub input as I am using the "Polk way" wiring. The 606 sub LFE is in "off". Surround is in "large" & center speaker is in "nmnl" mode. Rev/normal switch on sub appears to have no change in sound chara cteristics that I can tell. This system has mode options for pro-logic, Dolby digital, cinematic equalization, Pli-music, Pli-movie....and so on. Room is approx 16x13 leaving rear speakers close to the couch. Most listening is to TV and DVDs. Any suggestions?

Dear SS,
I downloaded the manual for your recvr, and discovered (after a 2nd read thru) that when you set the sub to 'off', your fronts AUTOMATICALLY go to lrg. Recommend setting the ctr, & surr.'s to 'nrml'
I'm attaching the manual in case you don't have it.
If you do have it, at the top, right hand column, under 'set-up', it explains what happens when setting the sub.:D

CamaroSS
12-28-2007, 11:36 PM
i really appreciate your research! i have been attempting to locate the manual as i have had this unit for quite awhile. was just about to go on web & download when i saw your reply. i very seldom have time to be on the computer & is usually late at night. gonna have to play a little with listening modes as i do not have HD TV & alot of local channels audio is garbled in the front & rear speakers, but center is ok. thanks again & i will try to do some experimenting tommorow evening after work. will let ya know how it goes.

vmaharaj
01-22-2008, 08:22 AM
Hi I am new to Polk Community but I am learning all the way. I am a self confessed tweaker and always looking for ways to improve speaker performance. I sent this email to Polk and I have not received any replies yet. Maybe any member can help me with this...

Dear Polk Audio,

I am running RTi A3 as my fronts and PSW 505 subwoofer with an Onkyo TX-SR605 AVR. As usual, it seems on your website I am confused with the issue of subwoofer connection. The Polk recommended way certainly seems to produce better bass in my system. I connected the front speakers and subwoofer via parallel connection (figure 7 in your PSW 505 documentation [see below] – I did it to reduce the speaker wire and keep things looking neat) to each speaker. However, I have a question which was raised by Onkyo.

Please see excerpt below:

The subwoofer "pre out" of the receiver is using a filter.

If you need full band, then connect the subwoofer to front speaker outputs left/right.

Only possible if the subwoofer has the possibility? If the subwoofer has the possibility, in this case switch subwoofer to "OFF" at the receiver menu.

If you use the front speaker outputs for the subwoofer, please attention.

Important info !!!

General our receiver can work with impedance from 4 ohm per channel.

Impedance lower is not allowed.

If you use two loudspeakers directly per channel, please give attention of the entire impedance, that this is not lower than 4 ohm!

For example, if you use two 4 ohm speakers per channel is the entire impedance 2 ohm. That is not possible to use!!!

If you use together a 4 ohm and 8 ohm speaker per channel, then is the entire impedance approximately from 3 ohm.

That is not possible to use!!!

If you use two 8 ohm speakers per channel is the entire impedance 4 ohm. You can use this.

In the case, if you use a active subwoofer about the “subwoofer pre out" of the av-receiver:

Please

1. Turn the volume at the subwoofer to maximum.
2. Turn the crossover frequency at the subwoofer to the highest frequency.


What are your recommendations in this case? What does the impedance issue become or does this not mean anything and will not compromise the AVR?

Erik Tracy
01-22-2008, 05:33 PM
Hi I am new to Polk Community but I am learning all the way. I am a self confessed tweaker and always looking for ways to improve speaker performance. I sent this email to Polk and I have not received any replies yet. Maybe any member can help me with this...

Dear Polk Audio,

I am running RTi A3 as my fronts and PSW 505 subwoofer with an Onkyo TX-SR605 AVR. As usual, it seems on your website I am confused with the issue of subwoofer connection. The Polk recommended way certainly seems to produce better bass in my system. I connected the front speakers and subwoofer via parallel connection (figure 7 in your PSW 505 documentation [see below] – I did it to reduce the speaker wire and keep things looking neat) to each speaker. However, I have a question which was raised by Onkyo.

Please see excerpt below:

The subwoofer "pre out" of the receiver is using a filter.

If you need full band, then connect the subwoofer to front speaker outputs left/right.

Only possible if the subwoofer has the possibility? If the subwoofer has the possibility, in this case switch subwoofer to "OFF" at the receiver menu.

If you use the front speaker outputs for the subwoofer, please attention.

Important info !!!

General our receiver can work with impedance from 4 ohm per channel.

Impedance lower is not allowed.

If you use two loudspeakers directly per channel, please give attention of the entire impedance, that this is not lower than 4 ohm!

For example, if you use two 4 ohm speakers per channel is the entire impedance 2 ohm. That is not possible to use!!!

If you use together a 4 ohm and 8 ohm speaker per channel, then is the entire impedance approximately from 3 ohm.

That is not possible to use!!!

If you use two 8 ohm speakers per channel is the entire impedance 4 ohm. You can use this.

In the case, if you use a active subwoofer about the “subwoofer pre out" of the av-receiver:

Please

1. Turn the volume at the subwoofer to maximum.
2. Turn the crossover frequency at the subwoofer to the highest frequency.


What are your recommendations in this case? What does the impedance issue become or does this not mean anything and will not compromise the AVR?

I think that there is some misinformation and confusion with wiring up subwoofers in "parallel" with front L/R speakers.

One would think, from basic circuit analysis, that parallel connections mean parallel impedances - and so effectively reducing the equivalent load seen by the AVR amplifier speaker outputs.

Meaning if you have an 8 ohm main front speaker and an 8 ohm subwoofer hooked the "Polk Way" in parallel that the equivalent resistance(impedance) would be 4 ohms.

However, and I'm not claiming to be an expert on this, if you are using a powered subwoofer, then there is NO additional load on the amplifier.

From an electrical analysis perspective, I can't offer an explanation, but I've read this on other subwoofer product information sites as well as here.

It makes sense.

Consider a situation where you have an LSi set of mains and an LSi powered sub - all rated at 4 ohms. If the powered sub presented a real load, then wouldn't that mean the 'equivalent' load would be 2-ohms??!!

Ahh...too much math....my head hurts now...I have to go lie down now ;)

Erik