Fun with RTi A speakers
F1nut
Posts: 50,647
Having been thoroughly impressed with the results of using Larry's rings on various SDA speakers I decided to do something similar to the RTi A7's, the RTi A6 and FXi A6's in my HT rig. As T-nuts were out of the question I looked around and found what are called Hurricane nuts at Parts Express with an 8-32 thread pattern. I also purchased a quantity of 8-32 x 7/8" stainless steel cap screws from Grainger. The Hurricane nuts are noted as working very well with MDF. They have 4 burrs cut in at the top of the post, which bite into the MDF from the twisting motion as they are drawn in place.
I knew before the start that this was not going to be an easy job and it turned out to be even more difficult than I imagined. There is not much of a mounting lip around the driver cut outs and the bottom front port cannot be removed entirely from the cabinet. As the round flange on the Hurricane nuts protruded too far into the driver cavities I used a Dremel with a heavy duty cut off wheel (a lot of them) to cut off part of the flange creating a flat side. I did these one at a time while held in a vise. This was not necessary for the tweeter or ports as there is ample MDF around the screw holes.
After removing the tweeter, drivers and small port from one of the RTi A7's, I used the recommended 13/64" drill bit to enlarge the existing screw holes. For the bottom port I had to hold it off on an angle in order to drill out the holes. Once the prep work was done I started with the easy ones, the tweeter and small port. While holding a nut on the back side of a new hole I used one of the new cap screws with a thick #8 stainless steel washer to draw the nut into the MDF. I used a T handle Allen wrench to start it off and finished up with screw gun set on high torque. For the drivers I used the same procedure, except that I had to start with part of the nut's flat side showing because as the nut is drawn in it twists. If done just right the nut will seat with none of the flange visible. Of course, this didn't always work 100%, so on some I had to use the Dremel with a grinding wheel to remove what little of the flange protruded. That all went smoothly enough, now the real fun began. The screw holes on the bottom port are extremely hard to get to from inside the cabinet. I had to reach in thru the bottom driver cut out, down past the bracing and contend with the tube for the port. Basically, my arm was inside the cabinet up past my elbow trying to feel around for a screw hole while holding a nut and trying like hell not to drop it. This part is not for those lacking patience or spacial relation skills. In reality, it isn't necessary to do this mod to the large port, but I wanted all the screw heads to match. After what seemed like forever, I was able to get the 4 nuts for the bottom port seated and started to remount the tweeter, small port and drivers. A few times the nut and cap screw wanted to cross thread. On those I used a 8-32" tap to clean up the nut threads. Keeping in mind that the bezels are plastic around all of these, I used caution when torquing down the new cap screws, but was pleased to find that I was able to snug them up tighter than I initially thought.
I left the bottom port for last and of course this is where things went very wrong. I had been starting the cap screws by hand, driving them in using the screw gun on low torque and then finishing with the T handle Allen wrench. On the very last hole of the port the nut and screw cross threaded (despite starting ok) while using the screw gun causing the Hurricane nut to strip out of the hole. I spent the next several hours trying to get a grip on the stripped out nut with various tools. After great difficulty, I was finally able to get a micro size vise grip on it and snap it off. Fortunately, I had a few of Larry's tweeter rings around and used the end of one as a substitute. I drilled out the hole a little larger to accommodate the larger diameter and used epoxy to glue it in place. The rest of the speakers went much smoother, thank God!
The end result made the effort worthwhile. There is more presence and weight to the mid-range as well as more punch to the bass.
Before anyone considers doing this to their speakers, I want to warn you that this is not an easy job, there is very little room for error and it will take a lot longer than you might think.
Link for the Hurricane nuts, http://www.parts-express.com/pe/showdetl.cfm?PartNumber=081-1080
The stainless steel cap screws are available from many sources.
I knew before the start that this was not going to be an easy job and it turned out to be even more difficult than I imagined. There is not much of a mounting lip around the driver cut outs and the bottom front port cannot be removed entirely from the cabinet. As the round flange on the Hurricane nuts protruded too far into the driver cavities I used a Dremel with a heavy duty cut off wheel (a lot of them) to cut off part of the flange creating a flat side. I did these one at a time while held in a vise. This was not necessary for the tweeter or ports as there is ample MDF around the screw holes.
After removing the tweeter, drivers and small port from one of the RTi A7's, I used the recommended 13/64" drill bit to enlarge the existing screw holes. For the bottom port I had to hold it off on an angle in order to drill out the holes. Once the prep work was done I started with the easy ones, the tweeter and small port. While holding a nut on the back side of a new hole I used one of the new cap screws with a thick #8 stainless steel washer to draw the nut into the MDF. I used a T handle Allen wrench to start it off and finished up with screw gun set on high torque. For the drivers I used the same procedure, except that I had to start with part of the nut's flat side showing because as the nut is drawn in it twists. If done just right the nut will seat with none of the flange visible. Of course, this didn't always work 100%, so on some I had to use the Dremel with a grinding wheel to remove what little of the flange protruded. That all went smoothly enough, now the real fun began. The screw holes on the bottom port are extremely hard to get to from inside the cabinet. I had to reach in thru the bottom driver cut out, down past the bracing and contend with the tube for the port. Basically, my arm was inside the cabinet up past my elbow trying to feel around for a screw hole while holding a nut and trying like hell not to drop it. This part is not for those lacking patience or spacial relation skills. In reality, it isn't necessary to do this mod to the large port, but I wanted all the screw heads to match. After what seemed like forever, I was able to get the 4 nuts for the bottom port seated and started to remount the tweeter, small port and drivers. A few times the nut and cap screw wanted to cross thread. On those I used a 8-32" tap to clean up the nut threads. Keeping in mind that the bezels are plastic around all of these, I used caution when torquing down the new cap screws, but was pleased to find that I was able to snug them up tighter than I initially thought.
I left the bottom port for last and of course this is where things went very wrong. I had been starting the cap screws by hand, driving them in using the screw gun on low torque and then finishing with the T handle Allen wrench. On the very last hole of the port the nut and screw cross threaded (despite starting ok) while using the screw gun causing the Hurricane nut to strip out of the hole. I spent the next several hours trying to get a grip on the stripped out nut with various tools. After great difficulty, I was finally able to get a micro size vise grip on it and snap it off. Fortunately, I had a few of Larry's tweeter rings around and used the end of one as a substitute. I drilled out the hole a little larger to accommodate the larger diameter and used epoxy to glue it in place. The rest of the speakers went much smoother, thank God!
The end result made the effort worthwhile. There is more presence and weight to the mid-range as well as more punch to the bass.
Before anyone considers doing this to their speakers, I want to warn you that this is not an easy job, there is very little room for error and it will take a lot longer than you might think.
Link for the Hurricane nuts, http://www.parts-express.com/pe/showdetl.cfm?PartNumber=081-1080
The stainless steel cap screws are available from many sources.
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
"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
Post edited by F1nut on
Comments
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Jesse with a HT rig...blasphemy I say...blasphmy!!! :biggrin::eek:
It's about time you got with it there Jesse.
That project sounds like it was a real doozy but the efforts paid off big time. Glad things worked out so well especially when you describe the work around as having little room for error. Enjoy your new HT sound. Ready to go with a music server now & ditch the dinosaur disc spinner you have?
"2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up. -
Interesting results just from pulling the drivers in tighter. Why do you keep adding things to my "to do" list, Jesse? Nice description of the process. I appreciate the warning that this isn't as easy a job as it might seem! Did you snap any pics?
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Great write up Jesse.
A great tutorial for those attempting this project.
Well done Sir. -
Jesse - Would using a size one step down make this a bit easier? Knowing you as well as I do, I can picture that entire process....and I'm sorry, it's very funny. Why not just use a different thread design?CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
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On my RTA 12C's, which I did a bunch of work to about a month ago.
My technique for seating them was a little different. I removed all the drivers, drilled out the screw holes, pressed in the H-nuts by hand from the speaker interior (just enough so they would stay when I let go) and then forced them into the hole by tightening a C clamp from them to the front baffle.
Once they were fully seated I had no problems with getting the screws to thread.
I was surprised at how well they work as the teeth that prevent them from turning while tightening the screws are really small.
Cheers,
Fred"Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer -
blasphemy I say...blasphmy!!!
Tell me about it.Did you snap any pics?
No, sorry.Well done Sir.
Thanks!Would using a size one step down make this a bit easier? Knowing you as well as I do, I can picture that entire process....and I'm sorry, it's very funny. Why not just use a different thread design?
I'm not following you. What do you mean by a size one step down?
Yeah, I had to laugh a few times during the process to prevent the urge to make firewood out the speakers.
You mean something other than 8-32? Sure, one could use another thread pattern.and then forced them into the hole by tightening a C clamp from them to the front baffle.
I had thought about that method, but after reading others install comments the method I used seemed to be the preferred one.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 -
Sounds like a daunting project. But I must be missing something? Larry's rings are almost exclusively used in speakers that are not 'ported' and need a tight seal to sound their best. Rti-As have two ports? So I don't follow how this would help much--though I don't doubt your descriptions of improved sound. I just wonder why the sound was better.
Is it that there is 'less' resonance because the speakers are better anchored to their existing box? Or something else. (I admit that I'm a bit clueless here as the only thing I would've thought of doing to ported speakers is better internal damping and/or dynamating the bass drivers?).
cnhCurrently orbiting Bowie's Blackstar.!
Polk Lsi-7s, Def Tech 8" sub, HK 3490, HK HD 990 (CDP/DAC), AKG Q701s
[sig. changed on a monthly basis as I rotate in and out of my stash] -
Is it that there is 'less' resonance because the speakers are better anchored to their existing box?
Basically, that's it and it doesn't matter if the speaker is ported or sealed to benefit.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 -
Interesting.
Less resonance from the driver frames themselves perhaps? The whole point of the ARC port (the small port under the midbass) on RTxx series is that it is tuned out of phase with the resonant frequency of the cabinet itself. I wonder if your mod just took that a step further, or perhaps made the ARC port more effective?
Cheers,
RussCheck your lips at the door woman. Shake your hips like battleships. Yeah, all the white girls trip when I sing at Sunday service. -
F1,
Obviously my idea of fun and yours are not very similar! Glad to hear that it all worked out in the end.
NathanHome Rig
SDA 2.3TL's front and center
Polk 1000p Center
Pioneer Elite SC35 Receiver (Pre/Surround
Sunfire Cinema Grand 5X200-Back in the mix.
OPPO BDP-93
Squeezebox
Stepped up to name brand Speaker Cables and interconnects!
Monitor 4, 5, 7, 10's, SDA 1B's, 2B's, 2.3TL's, RTA 15TL's all in storage waiting for me.
Sales Rating #1!! -
I recently bought the RTI A7 were in use. It seems they did upgrade the local master - I mean what is the change in the crossover. Help with a picture of the original crossovers RTI A7 or circuits that I can fix it as it should be. And as I will be very grateful to the people who will be able to explain to me a bit of how good or bad my look crossovers. With master who touched them no opportunity to speak. I really like my speakers and I do not want to change them, but I'm a little disappointed in the fact that the master had done to them. P.s. I live in Kazakhstan. All many thanks for your attention.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
With master who touched them no opportunity to speak. but I'm a little disappointed in the fact that the master had done to them.
So the master did not touch them in a good way? Or is that what you are trying to figure out?
How many masters are doing this kind of touching over there in K-Stan?Lexicon RT-10, Parasound P5, McCormack DNA 0.5, Polk SDA CRS+, SVS Sub
Schiit Modi, Luminous Audio Axiom II, McCormack DNA-1, Digital Phase AP 2
Marantz AV7701, Emotiva XPA-5, Paradigm 11se Mkii, DCM Time Windows, NHT 2C, SVS Sub
Spares - Kenwood C1 Pre, NAD 2200PE, Polk Monitor 10B, Polk Model 11, other odds and ends -
With master who touched them no opportunity to speak. but I'm a little disappointed in the fact that the master had done to them.
So the master did not touch them in a good way? Or is that what you are trying to figure out?
How many masters are doing this kind of touching over there in K-Stan?
I bought them in that condition. I do not trust the masters of this level. I think the acoustics sound worse than the original. I want to return the columns of the native sound. I'm very sorry for them. The master was from Russia. I bought them there and brought back to Kazakhstan.
Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
If you see on the pictures is good or bad, he did tell me please. He put the increase in cross-section cable. Removed sintepon. He added big capacitor, and that it made with themselves crossovers. I can not say what. I think speakers can sound better.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
That looks like a real mess.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 -
Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
Can I ask somebody, the data on all the details and to restore the original image. I am very worried for my column.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
Yes, bad.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 -
Can I ask somebody, the data on all the details and to restore the original image. I am very worried for my column.
As they are current production speakers, Polk does not provide the schematics. Do you have a Polk dealer in Kazakhstan?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 -
I think only the small shops in the capital who resell acoustics.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
Ok, I have asked someone who might have a better idea than myself if they can find out what options are available to you in Kazakhstan. It may take them a while to come up with that information, so be patient.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 -
Ok, I have asked someone who might have a better idea than myself if they can find out what options are available to you in Kazakhstan. It may take them a while to come up with that information, so be patient.
thank you. I'm not in a hurry. I am aiming for the best result.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
In the meantime you may enjoy reading this, http://forum.polkaudio.com/discussion/159998/rtia7-and-csia6-crossover-upgrades-a-slightly-different-approach/p1Political 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 -
Those look almost like old Soviet Power Supply CapsHome Theater/2 Channel:
Front: SDA-2ATL forum.polkaudio.com/discussion/143984/my-2as-finally-finished-almost/p1
Center: Custom Built forum.polkaudio.com/discussion/150760/my-center-channel-project/p1
Surrounds & Rears: Custom Built forum.polkaudio.com/discussion/151647/my-surround-project/p1
Sonicaps, Mills, RDO-194s-198s, Dynamat, Hurricane Nuts, Blackhole5
Pioneer Elite VSX-72TXV, Carver PM-600, SVS PB2-Plus Subwoofer
dhsspeakerservice.com/ -
westmassguy wrote: »Those look almost like old Soviet Power Supply Caps
exactly. and it scares me. I think he just ruined everything.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
Hello,
The best source of information would be to email Kim Jasper at: Kim.Jasper@soundunited.com
He could tell you who the nearest Polk Audio importer is to your location. Also he might be able to send you replacement crossovers.
Regards, Ken -
KennethSwauger wrote: »Hello,
The best source of information would be to email Kim Jasper at: Kim.Jasper@soundunited.com
He could tell you who the nearest Polk Audio importer is to your location. Also he might be able to send you replacement crossovers.
Regards, Ken
hello! thanks for the info. I will write to him.Don't drink and drive - just smoke and fly )
Pioneer VSX 922-K + Polk Audio RTi A7 (by wrong bi-amping)
Flac and SACD by HDMI -
Hey Jesse,
I bought hurricane nuts per your lead.
As I move from speaker to speaker putting the finishing touches I've procrastinated about for several years, the mids & woofers will get the F1nut driver mount upgrade.
I've never thought much of stock screw - your review confirmed that.
Thanks for raising the bar, again! TonySamsung 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 “Foamed & Plugged**”, inside* & out
8 ga Powerline: LR woofers, inside* & out
*soldered **Rob the Man (Xschop) LR: Tri-amped RTi A7 w/Rotels. Woofers - 980BX; Tweets & Mids - 981, connected w/Monoprice 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
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