Tri-amped RTi A7

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  • gp4jesus
    gp4jesus Posts: 1,969
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    Trey’s custom RTi A7 diffraction pads
    1eif2fpr54lr.jpeg
    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
  • F1nut
    F1nut Posts: 49,886
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    That's a lot of pad. Any impressions?
    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

  • VR3
    VR3 Posts: 28,156
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    Looks great!
    - Not Tom ::::::: Any system can play Diana Krall. Only the best can play Limp Bizkit.
  • gp4jesus
    gp4jesus Posts: 1,969
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    F1nut wrote: »
    That's a lot of pad. Any impressions?
    Very inexpensive tweak!

    Speakers more transparent, instruments more defined.

    Any GRP and in particular, (on Sheffield) Dave Grusin’s “Discovered Again.” Like the musicians are in front in you, in the room!

    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
  • gp4jesus
    gp4jesus Posts: 1,969
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    VR3 wrote: »
    Looks great!
    a credit to your dedication to your craft!

    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
  • xschop
    xschop Posts: 4,749
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    Decapitated this dedicated midrange....

    hip4udc6palp.jpg
    Don't take experimental gene therapies from known eugenicists.
  • xschop
    xschop Posts: 4,749
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    If a 6.5" OD x 4.5" long cylinder can fit up thru the cabinet from top woofer hole to the midrange hole, then a schedule 80 pipe can be used to compartmentalize the midrange. You would only loose just a couple cube inches of volume...

    3wjhz594pw9n.jpg
    Don't take experimental gene therapies from known eugenicists.
  • gp4jesus
    gp4jesus Posts: 1,969
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    The “A7 schedule 80” mid* closure. Xschop’s (Rob) practical work around in place of a divider to separate the same* from the woofers. I believe for one to realize best results, they should pursue active bi-amping the woofers and mids plus upgraded mid/tweeter passive XO parts.

    In pursuit of Rob’s brainstorm, I’ll take measurements of the space inside the closure brace that’s beneath the “mid port” and the upper woofer. Further, following reassembly, I’m gonna test via RTA if stuffing that mid port affects the frequency response much if any.

    Thanks for your ideas, Rob.

    Tony
    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
  • xschop
    xschop Posts: 4,749
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    Just suggested it as the piece of sch 80 I still have for 6500 gasket template also fits these RTiA mids perfectly. You could mount them by clocking 4 countersunk fasteners 45 degrees on the cabinet flange that sits right beneath midrange flange.

    In this instance, you'd still want to foam the inside of the frame baskets and stuff the new cylindrical chambers with dacron/wool etc.
    Don't take experimental gene therapies from known eugenicists.
  • xschop
    xschop Posts: 4,749
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    Also an interesting caveat about these mids is that the spiders look like they've relaxed at a slightly forward position by @ 0.050" (perhaps due to shared cabinet volume with woofers exerting pressure?)

    That 0.050" difference is the only difference between a mw6500 phase plug and this one's required base length.
    Don't take experimental gene therapies from known eugenicists.
  • gp4jesus
    gp4jesus Posts: 1,969
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    Hmmm… I finished the pre-Tri amp “surgery” over 5 1/2 years ago - nearly half their lifetime w/me.

    OTOH I uncovered the ‘A7s bass heavy/”spirited”volume “mid” driver problems shortly after purchase. That’s when I began some internal rewiring and trying other “band-aide” type tricks to cope w/the problems.

    More later, gotta navigate
    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
  • Gardenstater
    Gardenstater Posts: 4,211
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    xschop wrote: »
    Decapitated this dedicated midrange....

    hip4udc6palp.jpg

    Aluminum voice coil former with 4? holes to help cool the voice coil? How permeable to air is that dust cap?
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
  • xschop
    xschop Posts: 4,749
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    ZERO permeability to atmosphere. It's like a butyl material and heavier than classic MW woven dust caps.
    Don't take experimental gene therapies from known eugenicists.
  • xschop
    xschop Posts: 4,749
    edited June 2022
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    Ace was back at delivery work...Im going to try and re-align the flange on left that is .200" bent and the VC is rubbing, although magnets are not shifted (assuming since large magnet shield won't budge even with small prybar) I checked with shims as Coil clears either side except when relaxed also.

    akah51cp8z24.jpg
    Don't take experimental gene therapies from known eugenicists.
  • xschop
    xschop Posts: 4,749
    edited June 2022
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    These uprights are weaker than classic MWs that can take more abuse.

    h4l049bga4h4.jpg

    I also find it interesting that the much thicker surrounds aren't actually glued on to frame like classic MWs. Both this one and good one can easily peel back the surround....

    8agy6qw4avmu.jpg

    This came in handy in this situation.
    Locked frame into my articulating vice without damaging the surround. Bent it back to 90 degrees vert. using a small prybar on the compressed frame pivoting off vice jaw base and VC looks like it's realigned about perfect. No rubbing while pushing on cone any direction...


    ts8653da8dtb.jpg

    urr9efph9wgo.jpg









    Don't take experimental gene therapies from known eugenicists.
  • Gardenstater
    Gardenstater Posts: 4,211
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    Yikes! Amazing! That's not for the faint of heart. :)
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
  • gp4jesus
    gp4jesus Posts: 1,969
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    xschop wrote: »
    These uprights are weaker than classic MWs that can take more abuse.

    h4l049bga4h4.jpg

    I also find it interesting that the much thicker surrounds aren't actually glued on to frame like classic MWs. Both this one and good one can easily peel back the surround....

    8agy6qw4avmu.jpg

    This came in handy in this situation.
    Locked frame into my articulating vice without damaging the surround. Bent it back to 90 degrees vert. using a small prybar on the compressed frame pivoting off vice jaw base and VC looks like it's realigned about perfect. No rubbing while pushing on cone any direction...


    ts8653da8dtb.jpg

    urr9efph9wgo.jpg

    May you have wisdom of Solomon coupled w/ strength of either Samson or the Hulk to complete this incredibly demanding task.

    Tony


    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
  • gp4jesus
    gp4jesus Posts: 1,969
    edited August 2022
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    owo4bjtgs0iw.jpeg
    vmaret5ayyab.jpeg
    The first “plugged” RTi A7 mid w/ painted trim ring. I found I prefer flat black. Even matte black to me appeared too glossy next to the Polk finish.

    ibcmv6lldaqv.jpeg
    Another painted “detail.”

    More pics of this ‘A7 w/ details & tips to Hurricane nut mids & woofers to follow. Earlier tonight I returned the above* ’A7 in its current state of mods to it’s rightful place as the “R” tower. My son helped me move the “L” tower twin to my shop to begin bringing it current w/ the former*.
    Post edited by gp4jesus on
    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
  • xschop
    xschop Posts: 4,749
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    Those look slick. The felts look factory too.
    Polk should take some design cue here.
    Don't take experimental gene therapies from known eugenicists.
  • gp4jesus
    gp4jesus Posts: 1,969
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    xschop wrote: »
    Those look slick. The felts look factory too.
    Polk should take some design cue here.

    Thanks but I can only take credit for providing the cash. Trey deserves most of the credit - he (laser) cut them! He also gets 5 stars for patiently working w/me on the shape.

    LH tower in progress. I’ve applied the first coat to the Woofer trim rings. Meanwhile I’m about to begin filing flat spots on 12 H nuts.

    Stay tuned!
    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
  • xschop
    xschop Posts: 4,749
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    Yes, Polk should hire Trey.
    Don't take experimental gene therapies from known eugenicists.
  • gp4jesus
    gp4jesus Posts: 1,969
    edited September 2022
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    Some tools and tips to Hurricane nut (H nut) your speakers:
    s5b2s3ddf1f2.jpeg
    6opj5sak1m03.jpeg
    a 9/64” tip & a Craftsman* cordless screwdriver. I use it* like a regular to crack the screws loose. Then at slow speed, have the motor do the rest.

    wey3a02ohk3b.jpeg
    5accqpi98gxr.jpeg
    Views of jig using channel locks, & 2 parallel clamps to hold two H nuts, w/one of those 8-32 screws through them. A mill **** file makes quick, easy work to file a flat spot…
    8om54cc0h4il.jpeg
    …a bit bigger than 9/16” across. This needs more filing.

    ogr9dlwk1y2g.jpeg
    27psxvpyk0b2.jpeg
    you’ll need a #7 drill bit as the original holes are too small

    ekw5lykktoay.jpeg
    Drill gently. Getting too aggressive makes an off-set hole…

    etu0ufwfwbk8.jpeg
    …then carefully shave the rough stuff w/ small sharp knife or utility knife blade.

    Cont’d in next post
    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
  • F1nut
    F1nut Posts: 49,886
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    A Dremel with a cut off wheel works a helluva lot faster for cutting off that piece of flange. If you try to install hurricane nuts for the bottom port I suggest finding someone with very small hands. I tore my hand up installing mine.
    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

  • gp4jesus
    gp4jesus Posts: 1,969
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    yzhj1rq8hfny.jpeg
    These slip join piers are helpful during the actual H nut install

    pfwy78elv2nd.jpeg
    If you’ll look very closely at the thin part of the nut, you’ll see a diagonal swirl of metal going left-to-right down the side. During install, that causes the nut to rotate clockwise. So if you begin…

    0m3s3dj8i9lv.jpeg
    …w/ a tiny bit more than you see showing here…

    z6ms0mtoce4o.jpeg
    …when inserted, it should look like this.

    I hope this makes sense. I discovered I could use 2 #8 washers & an 8-32 screw to “pull” the H nut up into the hole.

    qrwpqmdcqcg5.jpeg
    This example is partly finished. Note the washers under the screw head.

    1. Tighten the screw w/your fingers until the H nut makes contact underneath.
    2. use the Craftsman like a regular screwdriver to turn the screw
    3. After about 2 full turns, grab wide part of H nut w/ the slip joint pliers.
    4. As you further tighten the screw very slowly begin to rotate the pliers clockwise (you’re almost finished) keep an eye underneath. Slight over or under rotation of the wide part is ok.

    740omcxhqiq5.jpeg
    a test fit minus trim ring to make sure the screws go in easily. Remove screws then…

    w2uockqpn52f.jpeg
    …float the ring above the front baffle while putting the screws in just a couple of turns. Once they’re all in, turning easily, the ring should drop into place. Continue by giving each 1-2 turns, then move to the next. I used the tip holder to finish “hand tight.” Then used the Craftsman I gave each by hand no more than about 1/4 turn. Then move on to the next driver.

    I neglected to mention at the top of this series of posts, I had decided to finish “H nutting” the woofers after remounting the now “H nutted” & plugged mids. I chose to document the process for those that have considered doing this and some of the tweaks they’ve read about on the forum.


    Enjoy! Tony



    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
  • gp4jesus
    gp4jesus Posts: 1,969
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    F1nut wrote: »
    A Dremel with a cut off wheel works a helluva lot faster for cutting off that piece of flange.
    Yeah…but I already had the file. 3-4 maybe 5 minutes tops. I realize a Dremel is a useful tool though.
    F1nut wrote: »
    If you try to install hurricane nuts for the bottom port I suggest finding someone with very small hands. I tore my hand up installing mine.
    I’m certain you’re right about that. I looked at that…again. If you had not noticed I limited the port to paint.

    My Center is next. Very soon BTW

    Meanwhile in a few years after “the herd thins…”
    I’ll relocate the system to a different (bigger) part of the house…
    I’ll expand to 7 channels and…do a few things I’ve dreamt about for 30+ years and…



    …well…we’ll see.

    Cheers Jess. Tony
    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
  • gp4jesus
    gp4jesus Posts: 1,969
    edited September 2022
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    So. Was all the work worth it? You bet it is!

    I’m also more satisfied w/their appearance, too now that more of the formerly silver is black, save for the tweeters and their bezels. Stay tuned to my CSi A6 thread.

    I tested the improvements listening to Dave Grusin's "Discovered Again" on Sheffield. I experienced sounds, musical textures, & details I never heard before! "Plugging" in addition to the incredible “bang for pennies” "foaming*" of the frames are both worthwhile. For any music lover using RTi or RTi A series speakers, get in touch w/ the man - Xschop! He’ll hook you up.
    *find Gardenstater’s Foam thread

    Some details about the session:
    1. To minimize distractions, I limited output to just the mids, EXO'd 125 & 2.2K. Tweeters* and woofers** kept silent by either disconnecting* or leaving the power** off**.
    2. I played it on my 10 year old Samsung Blu-ray player, requiring me to force the Outlaw to 2 channel. My Philips CD player would caused the Outlaw to default to the same. Further my CD player's digital out jack has become intermittent but I’m confident I can repair it.
    3. It's tough to get the living room to myself. In my hurry I forgot to allow time for the amps to warm up before the session. Next time…

    The only variables from "pre-plugged" are the phase plugs, a 😬😢bare* floor* (it's complicated*) & one of the '7s already had an H-nutted mid. Per George, while the mount is more secure, they affect driver coupling only slightly, if at all. Soooo...

    I look forward to future similar listening sessions of just mids w/ other material eventually full range.

    I neglected to mention in the H nut series, I believe Polk never intended for their screws to ever come out. Voice of experience - they’re VERY easy to strip! ALWAYS hand tighten. Should you decide to “foam” and “plug” your mids, a single removal and careful remount w/no future tweaks planed should not compromise the closure screw holes.


    Divertiti ad ascoltare!
    (Enjoy your listening!)

    Tony






    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
  • xschop
    xschop Posts: 4,749
    edited September 2022
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    Any detection of low-mid bass attenuation?
    Don't take experimental gene therapies from known eugenicists.
  • gp4jesus
    gp4jesus Posts: 1,969
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    No. Consider…

    My pre-plug listening test using the same
    CD,
    BDP
    XO frequencies
    only the mids powered
    one mid was “foamed,” one was not.

    The ONLY frequency response difference I could hear was an undeniable raspiness at the top of the unfoamed mid’s range. That detail aside, I also listened to each channel separately. I repeated the same w/my 16 year old daughter w/out telling her why.

    We agreed the only difference we heard was
    a raspy top end from the unfoamed mid.

    You can read my post “plug” comments in an earlier post.

    I hope that answers your question, Rob

    Tony
    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
  • xschop
    xschop Posts: 4,749
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    Good deal. Nothing like real world experimentation.
    Don't take experimental gene therapies from known eugenicists.
  • Gardenstater
    Options
    As expected! Thanks Tony!

    Polyurethane Open Cell Acoustic Foam. The smallest thickness they have data for is 1/2". Imagine what 1/4 or 1/8" would be like.

    bcev5rqqe59v.jpg
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Onkyo A-8017 integrated
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform