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"R" Series Polks & Their Crossovers on a TX-SR605...

Peter Marlowe
04-28-2009, 09:26 PM
Was having this conversation with another Polk/Onkyo '605 owner, and wanted to clear the air about something, if anyone could help...

I am running a full suite of "R" series Polk bookshelves (along with a CSi center and PSW sub) in a 5.1 arrangement, connected to an Onkyo TX-SR605; the speakers being used are the following: The mains are larger R20 bookshelves, the center is a CSi30, the sub is a PSW10 and the surrounds are two smaller R15 bookshelves. Based on THX recommendations and findings by my installer who worked on putting the system in with me, ALL channels at the Onkyo's speaker crossover setup menu are set to rolloff at 80Hz. Is this okay for the larger R20 Polks and smaller R15s as well? Again, these aren't towers but bookshelves all around.

Also: If DVDs carrying "Dolby Surround EX" or "DTS-ES" soundtracks are played on a system with a 5.1 arrangement without the added "back surround channel(s)" to properly play back the added "information" in the EX or ES tracks, what happens? Does that EX or ES information just "collapse" into the standard surround channels? I ask because I am having some issues with the way my receiver displays ES or EX when playing back discs of this type -- when I play ANY title that carries an EX or ES track, my Onkyo's display NEVER reads "Dolby D EX" or "DTS-ES" as it should, and I am wondering if this is because based on how I have the receiver set up for only 5.1 channels, it "knows" to simply drop into standard Dolby Digital or DTS on EX or ES signals...could this be?

Thanks in advance...:)

kamspy
04-29-2009, 01:58 AM
80hz seems a bit low.

I'm using Monitor 60 towers right now and I cut it off at 120hz.


I guess it really depends on the dexterity of your subwoofer.

Best bet is to change between them with a variety of scenes (I'm sure you have a couple old DVD players you could hook up and do a A-B-C comparison.), and see which setting sounds the best.


There isn't a definitive answer to the question, but I can say with certainty that 80hz is a bit low for entry level Polk bookshelf speakers. Not downing, Polk, I own two set's and love the brand. Just being realistic.

m_vanmeter
04-29-2009, 07:57 AM
for the small R series bookshelf speakers, set your x-over at 100 Hz or higher. While the spec's say they can go down to 65 Hz, let your subwoofer do the heavy lifting and keep the bookshelf speakers in their comfort zone with the slightly highter x-over setting.

Stew4HD
04-29-2009, 08:51 AM
for the small R series bookshelf speakers, set your x-over at 100 Hz or higher. While the spec's say they can go down to 65 Hz, let your subwoofer do the heavy lifting and keep the bookshelf speakers in their comfort zone with the slightly highter x-over setting.

Well said. I have a set of Aperion book shelf speakers and the mfg recommends a x-over setting of 100hz even though the speakers can handle 80hz. I played with the x-over, just for grins and 100hz for the fronts, center is the sweet spot, IMO.

Peter Marlowe
04-29-2009, 03:29 PM
Thank you, guys, for all your replies and suggestions...they're appreciated.

But let me ask...while the concensus here seems to be 100Hz, would that apply to just the two main LARGER R20 Polks, or for all the speakers?

Again...the two mains are larger R20s, the center is a CSi30 and the surrounds are smaller R15s...would the 100Hz setting apply to all the speakers?

I will look up information by the manufacturer on these models as well, and perhaps even e-mail Polk, but I was just curious if any of you could shed some insight.

Peter Marlowe
04-29-2009, 03:40 PM
for the small R series bookshelf speakers, set your x-over at 100 Hz or higher. While the spec's say they can go down to 65 Hz, let your subwoofer do the heavy lifting and keep the bookshelf speakers in their comfort zone with the slightly highter x-over setting.

Thanks Van,

When you say "the smaller" R series, do you mean my R15 surrounds as opposed to the R20 mains? On set is definitely smaller than the other...

m_vanmeter
04-30-2009, 10:44 AM
I guess I meant anything smaller than the R50 towers. I would apply the 100 Hz cross over to all the speakers. You could certainly do a quick test though. Set everything other than the R20's to 100Hz and then the R20's to 80Hz and play a really demanding scene in a favorite movie. Listen closely to the R20's for any distortion or muddy sound in the lower frequencies. Then immediately reset the x-over to 100Hz and try the same scene again. Pick the setting you like best.

Peter Marlowe
04-30-2009, 11:28 AM
I guess I meant anything smaller than the R50 towers. I would apply the 100 Hz cross over to all the speakers. You could certainly do a quick test though. Set everything other than the R20's to 100Hz and then the R20's to 80Hz and play a really demanding scene in a favorite movie. Listen closely to the R20's for any distortion or muddy sound in the lower frequencies. Then immediately reset the x-over to 100Hz and try the same scene again. Pick the setting you like best.

Thanks again, Van -- I will look more closely into this when I have a free moment...

Peter Marlowe
04-30-2009, 03:23 PM
Hey Van and Guys,

I wanted to share with you a "tip" someone else on a Polk enthusiast site suggested to me regarding the same question, and see what you thought of his assesment; he said:


"In general, the rule of thumb is about 80hz crossover points all around. I wouldn't go as high as 120 unless the speakers weren't capable of reproducing those frequencies. Both of your speakers are capable of reproducing frequencies down to at least 65 hz at -3 Db(give or take for in room extension), so I'd leave them at 80 hz. I've found that crossing them at 100-120 provides a really undesirable emphasis on the upper bass and lower midrange areas."

Seems like he's saying 80Hz all around, as I had it set, but I'm waiting to hear back from him on a reply I gave to this response.

Would leaving a setting of "80Hz" for the small surround R15s really "hurt" anything -- and for the center CSi30 for that matter?

fr8mvr
04-30-2009, 03:35 PM
I have the R20s as fronts and R15s as rears. I set the Crossover at 100mhz using a Onkyo 606. I feel this works best since the R20' have a decent midrange. I also have all my speakers set to small.

Peter Marlowe
04-30-2009, 04:22 PM
I have the R20s as fronts and R15s as rears. I set the Crossover at 100mhz using a Onkyo 606. I feel this works best since the R20' have a decent midrange. I also have all my speakers set to small.

Thanks for your input; how long have you had these Polks in your system? Mine are a good number of years old now; do you have any pics of your setup that you can share?

You have ALL speakers set at 100Hz for crossover?

fr8mvr
04-30-2009, 04:29 PM
I have had mine for about 5 years and yes all are set for at 100Hz. I use auto set up and then set the crossover.

Peter Marlowe
04-30-2009, 04:37 PM
I have had mine for about 5 years and yes all are set for at 100Hz. I use auto set up and then set the crossover.

Yeah; mine are about five years old as well. They got carried over from a previous system powered by an Onkyo TX-SR600...

The Auto Setup routine on my '605 didn't set my speakers right; it pegged them as Full Range, which isn't correct because there's a sub in the system and these are bookshelf models. I overrode that and did manual calibration levels and crossovers, etc.

Do you have a pic of your system that you can share? Just curious to see how other R20 owners are running their gear...do you have yours on stands or are they wall-mounted?

Do you think there is any downside or "danger" to running the 15s, 20s and CSi30 at 80Hz? It's a discussion I'm having with another Polk/Onkyo owner/friend...

BTW, your signature reads that you have an Onkyo "602"...is it a '606?

fr8mvr
04-30-2009, 05:35 PM
Mine sit on the floor nIt real Home theaterish

Peter Marlowe
04-30-2009, 05:49 PM
Mine sit on the floor nIt real Home theaterish

You're NEVER supposed to sit bookshelves on the floor! They're supposed to be ear level with stands; how do you get any response out of them that way?!! :eek:

P.S. Is your Onkyo a "602" or "606"?

fr8mvr
04-30-2009, 06:00 PM
Sorry 602, yeah I know for "perfect sound" they should be at ear height but sometimes you have to work with in your situation. I'll get some pics for you. :)

Peter Marlowe
04-30-2009, 06:01 PM
Sorry 602, yeah I know for "perfect sound" they should be at ear height but sometimes you have to work with in your situation. I'll get some pics for you. :)

Awesome...

What is prohibiting you from using stands or wall mounting?