Receiver/Amp for Rti A7s

captbrannigan
captbrannigan Posts: 6
edited December 2021 in Electronics
Hi, I'm new here and would appreciate some help getting the most out of some used speakers I bought while staying within my budget.


Background: I have a Onkyo TX-NR656 with Velodyne CHT-FRSGV center & surrounds. I was using Polk T50 fronts and a BIC 12" sub, but those were recently stolen. My living room is about 17'L x 15'W x 12'H with my couch about 11' back from TV. I have two spare CHTs from the box set I got, but I don't really have a good place to hook them up for 7.1. I've been satisfied with 5.1 and only upgraded the fronts to the T50s a year ago.


Speakers: I found some used RTI A7s in my area for $250 and that seemed like a great deal so I picked them up. They are in great condition except they are missing the grilles and one subwoofer driver is cracked, which I plan to contact Polk about for replacements. I found a RD7225-1 on Ebay and it seems like nearly the same driver, would that work?


Receiver/Amp: I was already planning on upgrading my receiver for 4k/60, as I have a LG C1 that I use for an XSX and Steam Big Picture from a laptop 3070 and I would prefer to connect through the receiver rather than the current workaround of using ARC to connect directly to TV for 4k/60. I had been looking at the Onkyo TX-NR6050 and Denon AVR-S760H, both for sale at Costco for ~$500. Looking into other forum posts about A7s, it sounds like they really benefit from external amplification. I can't really evaluate the current volume & clarity of the A7s with the one cracked sub, as it already produces a distracting amount of burping near my preferred listening volume.

Given a budget of $1000, is there any option for a 4k/60 receiver with preouts and an amp? A cursory google search only found 4k/60 receivers with stereo pre-outs in the $1500 range + I'd need the amp on top of that.


Subwoofer: I don't crank the bass and generally prefer just enough for it to stand up in the mix without vibrating my sternum. As such, the $200 sub I'd had for the last 15 years was set to about 1/3 volume and served me well. While I look for a replacement, would it be possible to wire the subs of the A7s up as the sub for 5.1 (I guess technically it'd be 5.4 in this setup, lol)? It's probably not worth the headache compared to playing around with my receiver cross over to get more bass response. It would just be splitting off power that's currently running to them anyways, right?

Related to my previous question, could I skip out on a dedicated sub by just getting an amp and bi-wiring the subs on the A7s? IE, instead of budgeting $1000 for receiver and $300 for sub, could I put that $300 into an amp and end up with more power to the subs and mids of the A7s netting equivalent bass response to a dedicated sub but with the added bump in mid range?


Thanks in advance for any help or input.

Comments

  • F1nut
    F1nut Posts: 49,602
    The RTiA7 has two woofers, they are not subwoofers. For a 5.1 HT rig you need a dedicated subwoofer. You also need a matching center channel, either the CSiA4 or CSiA6. Forget bi-wiring or bi-amping and for the time being forget about a separate amplifier, just get a really good AVR.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • captbrannigan
    captbrannigan Posts: 6
    edited December 2021
    Given my budget, I think I might be better off sticking with the receiver I have.

    TX-NR656 (owned, IIRC ~$350)
    100 W/Ch (8 ohms, 20 Hz–20 kHz, 0.08% THD, 2-ch driven) [same for the following]

    TX-NR6050 $500
    90 W/Ch

    AVR-S760H $550
    75 W/Ch

    AVR-X2700 $1000
    95 W/Ch

    AVR-X3700 $1500
    105 W/Ch (has pre-outs)

    It doesn't look like I gain much amplification from hdmi 2.1 receivers in my price range. I'd have to push up to $1500 plus an amp to see a difference. I'm only going off quoted specs, so it could be real world performance (actual power output, EQ, etc) shows more differences between these receivers.


    Shopping for a subwoofer, I'm pretty tempted by Monoprice's offerings. The SW-15 for $250 looks like a decent upgrade from the BIC H100 I paid $200 for 15 years ago. Those Monolith 12 and 15 subs (the 10 is sold out) look really, really nice but I don't think I can afford to put $700/$1100 into something I probably won't take advantage of. I know higher quality subs are not only for higher volume but also lower frequency output, so I am tempted that maybe my negative experience with subs comes from excess volume from low quality drivers. I do like the rumble in a movie theater, but for music I just find it uncomfortable to feel my chest vibrate.

    If I skip upgrading my receiver and continue using ARC for 4k/120 (I kept saying 4k/60 earlier, I meant 120) I could put that money towards a much higher quality sub, but given how satisfied I was with the BIC I don't know if that would be worthwhile for me.


    Amazon/Crutchfield has the CSiA6 for $150. I know it's more important to match front and center speakers than surrounds, but I didn't bother to do that when I got the Polk T50s last year. I'm sure it would be a noticeable upgrade, not only for matching tone but going from 3.5" to 6.5" cones. I'm considering it, but my funds are limited. For my preferences, it probably makes more sense than upgrading subwoofers tho...
  • tonyb
    tonyb Posts: 32,897
    edited December 2021
    Your current receiver lacks any inputs to allow yourself to add more power should you need it down the line. You should keep an eye out for one with preouts. The lack of being able to add a power amp will limit your choices of speakers latter on.
    HT SYSTEM-
    Sony 850c 4k
    Pioneer elite vhx 21
    Sony 4k BRP
    SVS SB-2000
    Polk Sig. 20's
    Polk FX500 surrounds

    Cables-
    Acoustic zen Satori speaker cables
    Acoustic zen Matrix 2 IC's
    Wireworld eclipse 7 ic's
    Audio metallurgy ga-o digital cable

    Kitchen

    Sonos zp90
    Grant Fidelity tube dac
    B&k 1420
    lsi 9's
  • Denon AVR-X2700H for $1000 has 95 W/Ch and zone 2 pre-outs, but I've heard mixed things about mixing multichannel and zone 2.

    I don't see any 8k Marantz receivers under $1000. The NR-1711 for $1000 has 50 W/Ch and pre-outs for only the fronts.

    Yamaha RX-V6A for $700 might be a good option. It has 100 W/Ch, front only pre-outs, but is waiting on a firmware update for full 4k/120.


    I called Polk support and got replacement grilles and 7" driver for the cracked woofer for $106. Once I get that replaced I'll have a better idea of whether the current power is sufficient or I need to amplify them.


    Thanks for the suggestions so far, I appreciate how helpful everyone has been.
  • captbrannigan
    captbrannigan Posts: 6
    edited December 2021
    Couple things..

    I was looking at an older product listing for that Yamaha RX-V6A. To support full 4k/120 you have to send it in to Yamaha to replace the HDMI board.

    I found out that my TX-NR656 has powered zone 2, but also has a setting to connect a pre-main amplifier. Google tells me that's a combo pre-amp/amp. So as long as I'm willing to continue putting up with using ARC to get 4k/120 I could hook up an amp to my speakers using my existing receiver. I'm a bit hesitant to try that though, since I've heard vague whispers that having your front speakers connected as zone 2 can cause issues. Is this something to be concerned about, or more of a legacy issue for older receivers?

    While digging around in my user manual, I also discovered that I can bi-amp the fronts using the surround back plugs. I don't have space to put surround backs anyways, so this seems like a no-brainer to try once I get the new woofer installed this weekend.
  • F1nut
    F1nut Posts: 49,602
    You cannot bi-amp with an AVR. It's marketing BS. To bi-amp you need two separate power amps and to do it right, active crossovers.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."


    President of Club Polk

  • Irrenhaus
    Irrenhaus Posts: 1,082
    HTAVR-Pioneer SC99XPA-DR3 Differential Reference AmpPolk R-700Rear- RT150Side- RT150Center-CSi5Sub-Rythmik audio F25Player- Panasonic DP-UB9000Projector- Optoma CinemaX P2Screen- Silver Ticket Products STR Series 6 120"Audio Room 2ch rig.Cary AE-3, Onkyo M-504, Marantz SA8005, Azur 851NWharfedale - Linton, SVS SB12-NSDMinis Forum PC (streamer) and Panamax MX5105Headphone rig;Schiit JOTUNHEIM and different headphones.Samsung 42" flat screen TV.
  • Irrenhaus wrote: »

    That doesn't have 8k / 4k/120hz. I'm sure if I wanted to stick with ARC running video through the TV first, I could find a cheaper receiver with pre-outs.

    Thanks for the suggestion though.
  • pitdogg2
    pitdogg2 Posts: 24,323
    Dude Why 8k? Where are you finding any 8k product, other than a very very few things on YT?
    Yes personally I think you need to send the signal to the TV first and let it do it's thing, remove one thing from the chain before the TV. Do you have an 8k tv?
  • captbrannigan
    captbrannigan Posts: 6
    edited December 2021
    pitdogg2 wrote: »
    Dude Why 8k? Where are you finding any 8k product, other than a very very few things on YT?
    Yes personally I think you need to send the signal to the TV first and let it do it's thing, remove one thing from the chain before the TV. Do you have an 8k tv?

    It's not about 8k/60, it's about 4k/120. I DO have both an XSX and an RTX 3700 laptop capable of outputting 4k/120 to my 4k/120 LG C1. When I manage to get my hands on a PS5, then all my TV inputs will be used up and if I want to hook up anything else for 4k/120 I'd have to unplug something and fuss around changing settings (everything needs a little tweaking to get the best picture).

    Using ARC occasionally only outputs stereo to my receiver instead of surround. I have issues switching between DD and DTS. Twice I've had to completely reset my TV because the audio bugged out and stopped outputting using ARC at all. It's something I can deal with for now, but if I'm going to spend 3x what I spent on my current receiver I don't see why I should still have to run everything through my TV first and use an AVR solely for audio.
  • pitdogg2
    pitdogg2 Posts: 24,323
    edited December 2021
    Gotcha carry on.


  • Ric5811
    Ric5811 Posts: 400
    edited December 2021
    Denon AVR-X2700H for $1000 has 95 W/Ch and zone 2 pre-outs, but I've heard mixed things about mixing multichannel and zone 2.

    I don't see any 8k Marantz receivers under $1000. The NR-1711 for $1000 has 50 W/Ch and pre-outs for only the fronts.

    Yamaha RX-V6A for $700 might be a good option. It has 100 W/Ch, front only pre-outs, but is waiting on a firmware update for full 4k/120.


    I called Polk support and got replacement grilles and 7" driver for the cracked woofer for $106. Once I get that replaced I'll have a better idea of whether the current power is sufficient or I need to amplify them.


    Thanks for the suggestions so far, I appreciate how helpful everyone has been.

    You'll need at last 100w per channel. With sufficient watts they sound great, I'm getting to ready to replace my Arcam with a new AV Receiver and getting away from separates, Mainly cost and wanting the new surround sound codecs, and to use HDMI. Going to plug my Firestick 4k straight to Receiver even though the new tv has eArc.

    I'm looking at the Onkyo TX-NR6100 or 7100, and also looking at Pioneer Elite AV.
    Polk RTi A7's FrontPolk CSi A4 CenterPolk Tsi 100's SurroundOnkyo TX-RZ50:)Oppo BDP 83 (Collecting dust)MIT Terminator 3 Speaker CableMIT Terminator 2 IC's (Oppo 2 chan)Signal Cable HT TWOEpson PowerLite Home Cinema 1080Hisense 55 U8GBelkin PF 60 Power Center
  • jeremymarcinko
    jeremymarcinko Posts: 3,785
    edited December 2021
    Take advantage of Emotiva’s 20% Emobucks holiday promo.

    Get their new processor and apply the $200 credit to the BasX A5 power amp. I don’t think you can do better than this for under $1500

    https://emotiva.com/products/basx-mc1-13-2-channel-dolby-atmos-dts-x-cinema-processor

    And

    https://emotiva.com/products/basx-a5-five-channel-power-amplifier

    Some here will tell you Emotiva is too bright for RTI/a, but it’s not in my experience and the pre/pro has a decent calibration system built in.
    Oh, Listen here mister. We got no way of understandin' this world. But we got as much sense of this bird flyin in the sky. Now there is a lot that bird don't know, but it don't change the fact that the world is happening to him all the same. What I am tryin to say is, is that the course of your life, well its changing, and you don't even see it- Forest Bondurant
  • gp4jesus
    gp4jesus Posts: 1,969
    I concur w/Ric5811: 100 quality WPC from an external amp is good start. More is better still.

    Except for the upscale, most AVRs advertise inflated power ratings.

    Side note: the A7s don’t mind a good sub “picking up the bottom octave or two of heavy lifting.”

    Happy New Year.
    Samsung 60" UN60ES6100 LED Outlaw Audio 976 Pre/Pro Samsung BDP, Amazon Firestick, Phillips CD Changer Canare 14 ga - LCR tweeters inside*; Ctr Ch outside BJC 10 ga - LCR mids, inside* & out 8 ga Powerline: LR woofers, inside* & out *soldered LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & “Plugged*” Mids - 981, connected w/MP Premiere ICs Ctr Ch: Rotel RB981 -> Bi-amped CSi A6 Surrounds: Premiere ICs ->Rotel 981 -> AR 12 ga -> RTi A3. 5 Subs: Sunfire True SW Signature -> LFE & Ctr Ch; 4 Audio Pro Evidence @ the “Corners”. Power Conditioning & Distribution: 4 dedicated 20A feeds; APC H15; 5 Furman Miniport 20s *Xschop's handy work