I'm the original owner of SDA-1C & finally (30+yr) at the point I can afford a great AMP.

2»

Comments

  • F1nut
    F1nut Posts: 50,622
    FraSerK wrote: »
    F1nut wrote: »
    now back to business...to reiterate I'm the original owner of SDA-1C & finally (30+yr) at the point I can afford a great AMP. What are some recommended 300-500+W AMPS that are compatible with the SDA 1C?

    Since wpc specs seem to matter most to you get a Crown pro amp.

    And it's you again...what matters most is "compatibility"...so I simply seeking advice from club polk... the club with a "heart" symbol in the logo... so show me some love my "polk" brother.


    You are getting the love you need, not the love you want.
    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

  • pkquat
    pkquat Posts: 748
    FraSerK wrote: »

    ...what matters most is "compatibility"...so I simply seeking advice from club polk... the club with a "heart" symbol in the logo... so show me some love my "polk" brother.

    You have gotten plenty of recommendations. We still don't know how much you want to spend. (I may have missed it, but I did scan the posts again). That is usually a factor and can refine any recommendations.

    As far as compatibility - synergy, a lot of people have said Parasound pairs well with vintage Polks. I agree. Good deals can be found on the used marked. If budget is not a concern, IMO it's hard to go wrong with a McIntosh.

    I'd suggest going to a higher end stereo store and listening to the different high end amps and speakers. If you notice differences, great, that will help define what you like in sound. If you don't notice much difference, the recommendations here won't make much difference. In that case a high wattage Crown will ensure you are not clipping the speakers and may meet your needs.

  • audioluvr
    audioluvr Posts: 5,592
    200 Lowly watts per channel. This is one of them

    811m2kqkoqbe.png
    Gustard X26 Pro DAC
    Belles 21A Pre modded with Mundorf Supreme caps
    B&K M200 Sonata monoblocks refreshed and upgraded
    Polk SDA 1C's modded / 1000Va Dreadnaught
    Wireworld Silver Eclipse IC's and speaker cables
    Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)


    There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus
  • Nightfall
    Nightfall Posts: 10,086
    edited August 2019
    FraSerK wrote: »
    what matters most is "compatibility"

    I'm pretty sure every audio amplifier is "compatible" with every audio speaker by strict definition. What does compatible mean to you in this sense? 3-500 watts and and Campbells soup can caps? You don't seem to be asking any questions about tone, imaging, etc.

    Then just get this and be done with it

    https://emotiva.com/collections/amps/products/xpa-2-gen3
    afterburnt wrote: »
    They didn't speak a word of English, they were from South Carolina.

    Village Idiot of Club Polk
  • I would like to add some Fidelity to this thread. I posted some questions and comments directed at the lovepolk general audience and some most specifically to individuals who are helpful and to those who offered net negative advice (CROWN, SHAMe ON YOU!). Overall this has been a very positive experience, thank you all for your contributions.

    Yesterday morning I bought a set of McIntosh MC2300. Last night I mono blocked each (600W) and cabled them to my L/R Polk Audio SDA1C's(500W).
    My wife (30+yr) who likes audio (not an audiofile), stoped by & sat down next to me on the couch... she said I never heard that before in this song... a few hours of listing later she started requesting specific artists etc... and then came the how do you turn this on/off (for when I am at work).
    A two for one deal...MC2300/SDA1C Fidelity and Fellowship on the couch.
  • pitdogg2
    pitdogg2 Posts: 25,498
    That sounds good but are you using the interconnect cable? How are these amps hooked up to the 1C?
    In most instances you'll need either a dreadnaught or AI-1 cable.
  • verb
    verb Posts: 10,176
    FraSerK wrote: »
    I would like to add some Fidelity to this thread. I posted some questions and comments directed at the lovepolk general audience and some most specifically to individuals who are helpful and to those who offered net negative advice (CROWN, SHAMe ON YOU!). Overall this has been a very positive experience, thank you all for your contributions.

    Yesterday morning I bought a set of McIntosh MC2300. Last night I mono blocked each (600W) and cabled them to my L/R Polk Audio SDA1C's(500W).
    My wife (30+yr) who likes audio (not an audiofile), stoped by & sat down next to me on the couch... she said I never heard that before in this song... a few hours of listing later she started requesting specific artists etc... and then came the how do you turn this on/off (for when I am at work).
    A two for one deal...MC2300/SDA1C Fidelity and Fellowship on the couch.

    Congrats on the MC2300's! I'm on a similar journey, with a pair of MC300's!

    As Ivan mentioned, be careful. If you are using an IC between the speakers, it must be either an A1-1 or Dreadnaught. If no IC cable is installed, it will work, but you lose the magic of the SDA.

    Let us know! :)
    Basement: Polk SDA SRS 1.2tl's, Cary SLP-05 Pre with ultimate upgrade,McIntosh MCD301 CD/SACD player, Northstar Designs Excelsio DAC, Cambridge 851N streamer, McIntosh MC300 Amp, Silnote Morpheus Ref2, Series2 Digital Cables, Silnote Morpheus Ref2 Series2 XLR's, Furman 15PFi Power Conditioner, Pangea Power Cables, MIT Shotgun S3 IC's, MIT Shotgun S1 Bi-Wire speaker cables
    Office: PC, EAR Acute CD Player, EAR 834L Pre, Northstar Designs Intenso DAC, Antique Sound Labs AV8 Monoblocks, Denon UDR-F10 Cassette, Acoustic Technologies Classic FR Speakers, SVS SB12 Plus sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable, Groneberg Quatro Reference IC's
    Spare Room: Dayens Ampino Integrated Amp, Tjoeb 99 tube CD player (modified Marantz CD-38), Analysis Plus Oval 9's, Zu Jumpers, AudioEngine B1 Streamer, Klipsch RB-61 v2, SVS PB1000 sub, Blue Jeans RCA IC's, Shunyata Hydra 8 Power Conditioner
    Living Room: Peachtree Nova Integrated, Cambridge CXN v2 Streamer, Rotel RCD-1072 CD player, Furman 15PFi Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi sub
    Garage #1: Cambridge Audio 640A Integrated Amp, Project Box-E BT Streamer, Polk Tsi200 Bookies, Douglas Speaker Cables, Shunyata Power Conditioner
    Garage #2: Cambridge Audio EVO150 Integrated Amplifier, Polk L200's, Analysis Plus Silver Oval 2 Speaker Cables, IC's TBD.
  • For anybody about to read the following, please do not automatically believe my configuration applies to your set up. You have to do your own research...or there is high risk of electrical DAMAGE (smoke!) to your AMP(s) and or the SDA Speakers themselves. Why: because the SDA interconnect creates an electronic circuit unlike no other type of speaker set. The type of AMP connected to the speakers becomes a major component of that circuit. The AMP is a high CURRENT power source that REQUIRES the correct electrical circuit CURRENT path, otherwise the CURRENT will find another path and cause electrical DAMAGE! Result your system is DEAD!

    I appreciate the cautionary dreadnaught or AI-1 cable interconnect measures from each above (pittdog2/verb), thank you for such a quick heads up reply to my last post! I've spent many weekends over the past couple months, just researching the AMP + SDA1x "compatibility" subject. And I believe I do not need either. Although I have read that the dreadnought / AI-1 does improve (person preference dependent) the sound quality of the SDA's. So maybe someday this will make it into my configuration.

    A KEY take away... quantity one (1) L/R "STEREO with COMMON GROUND" AMP is compatible with my *5th Gen SDA1C, & with the SDA interconnect cable attached.
    *my original owner purchase date & SN of my speakers correlate with 5th Gen.

    A KEY take away... quantity two (2) L/R "BRIDGED with COMMON GROUND" AMPs are compatible with my 5th gen SDA 1C , with the SDA interconnect cable attached AND the two AMPs COMMON GROUND MUST ALSO BE GROUNDED TO EACH OTHER.

    The McIntosh MC2300 are STEREO/BRIDGE COMMON GROUND.

    The McIntosh MC2300 COMMON GROUND IS ALSO COMMON CHASSIS GROUND.

    The COMMON CHASSIS GROUND IS electric circuit connected to EARTH GROUND through the round AC cord round GROUND post.

    So at this point one could rely on the house COMMON GROUND wiring to make the AMP to AMP GROUND circuit.

    HOWEVER that circuit choice is putting blind faith in the electricians work, the age of house wiring (no COMMON GROUND) etc... and is in the AC circuit (noise?) side of the AMP, vs the POWER GAIN side of the AMPs.

    So as an added AMP to AMP COMMON GROUND CIRCUIT INSURANCE I ran four (4) GROUND interconnects between the two APMs CHASSISs. Four might be overkill, but with combined 1200W too many can't hurt. These added GROUND interconnects also afford a shorter path between the two amp CHASSIS GROUND circuits vs. through the common AC ground circuit (house outlet). They are certainly more reliable, visually and electrically verifiable, for peace of mind. BTW I also ran connected between the AMP CHASSIS to AVReceiver GROUND connect.

    So after two days no smoke (yet?), the SDA is verified working and literally the wife has taken over the stereo.

    ken

    o7g0t183bzrs.jpg
    baabxc7vq9se.jpg
    tiu7hkcrl7cp.jpg

  • verb
    verb Posts: 10,176
    @fraserk very interesting approach to grounding the monoblocks together. I had thought about something like that, but apprehension got the better of me.

    When I reached out to McIntosh, they never suggested that approach. However, I’m glad that it worked out for you!

    And now that your wife has taken control, time for a secondary system just for you! :)

    Basement: Polk SDA SRS 1.2tl's, Cary SLP-05 Pre with ultimate upgrade,McIntosh MCD301 CD/SACD player, Northstar Designs Excelsio DAC, Cambridge 851N streamer, McIntosh MC300 Amp, Silnote Morpheus Ref2, Series2 Digital Cables, Silnote Morpheus Ref2 Series2 XLR's, Furman 15PFi Power Conditioner, Pangea Power Cables, MIT Shotgun S3 IC's, MIT Shotgun S1 Bi-Wire speaker cables
    Office: PC, EAR Acute CD Player, EAR 834L Pre, Northstar Designs Intenso DAC, Antique Sound Labs AV8 Monoblocks, Denon UDR-F10 Cassette, Acoustic Technologies Classic FR Speakers, SVS SB12 Plus sub, MIT AVt2 speaker cables, IFI Purifier2, AQ Cinnamon USB cable, Groneberg Quatro Reference IC's
    Spare Room: Dayens Ampino Integrated Amp, Tjoeb 99 tube CD player (modified Marantz CD-38), Analysis Plus Oval 9's, Zu Jumpers, AudioEngine B1 Streamer, Klipsch RB-61 v2, SVS PB1000 sub, Blue Jeans RCA IC's, Shunyata Hydra 8 Power Conditioner
    Living Room: Peachtree Nova Integrated, Cambridge CXN v2 Streamer, Rotel RCD-1072 CD player, Furman 15PFi Power Conditioner, Polk RT265 In Wall Speakers, Polk DSW Pro 660wi sub
    Garage #1: Cambridge Audio 640A Integrated Amp, Project Box-E BT Streamer, Polk Tsi200 Bookies, Douglas Speaker Cables, Shunyata Power Conditioner
    Garage #2: Cambridge Audio EVO150 Integrated Amplifier, Polk L200's, Analysis Plus Silver Oval 2 Speaker Cables, IC's TBD.
  • F1nut
    F1nut Posts: 50,622
    The common ground needs to be between the left and right channels, a chassis ground isn't going to cut it. However, a limited number of non-common amplifiers allow one to tie the negative outputs together, but you should always consult the manufacturer first. As always, the best and safest solution is to buy the audio quality Avel 800V isolation transformer. It doesn't cost much and even improves the sound quality when used with a common ground amplifier. That's not even up for debate, it's fact.
    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

  • BDT
    BDT Posts: 212
    I've found that Musical Fidelity amps and SDA go together pretty well. I had a Classe amp that I liked a lot as well.

    Don't get wrapped up in wpc ratings. Contrary to what people think......you don't need 300wpc for SDA's. A solid 100wpc amp with decent headroom is all you'll ever need and then some.

    BDT
  • Saturday evening update... since I first hooked the 2 MC2300 600W (mono block) to my original purchased 30 year old NOT (ZERO) modified SDA 1C, a few weeks ago.

    1st a shout out to verb & F1nut... thanks for your quick feedback on grounding and your dead end research with McIntosh... IMO they should have been able to give advice, but possibly they couldn't due to the Layer liability factor.

    F1nut, thank you... I have triple confirmed there is a common ground circuit between the L & R channels. And I will now integrate the audio quality Avel 800V isolation transformer, thanks for weighing in on this topic. Do you know anyone who has one built in the black box for sale?


    And now back to public square blog on the MC2300 L/R CHANNEL GROUND and the SDA 1C 5th Generation.
    The McIntosh MC2300 are STEREO & BRIDGE COMMON GROUND.
    The McIntosh MC2300 L/R COMMON GROUND IS ALSO COMMON CHASSIS GROUND. This CHASSI GND connect is shown on the top cover block diagram...speaker GND symbol is tied to CHASSIS/EARTH GROUND symbol. Before adding any circuit wires (4 total) between the two MC2300 I had removed the top and bottom covers, to validate the block diagram on top cover silkscreen was true. Once open I could visually confirm and with a DMM ohm out that the GROUND CIRCUITS. The GROUND is COMMON between L/R SPEAKER GOUNDS and too CHASSIS GROUND. I could also visually see CHASSIS GROUND CIRCUIT was connected to the 120AC GROUND lug. I still confirmed with the DMM ohm out the GROUNDs (all 3 L to R CHANNEL, CHASSIS & EARTH) are all COMMON. With visual and DMM conformation, I created a GROUND CIRCUIT (x4 interconnects) between the two MC2300 CHASSIS, Earth Ground and L / R channel GROUNDS. The added GROUND CIRCUIT makes the dual mono blocks compatible with the SDA 1C 5th Generation. So now after two more weeks... still no smoke and the SDA is still 100% functional.

    Two weeks ago I turned them on and I wanted to puke...
    Initial performance...loud...but the audio...something way wrong! Wife looking at me...why did you buy these AMPs, the old way sounded better. She was right and I felt like puking. I have been here before with 5.1, 7.1 etc...so no panic just need to think about it for awhile. So I made a few AVR configuration changes...and that improved the sound some and I kept the volume under control. It was good enough to coast through the rest of weekend...but not anything near what I was expecting. I really started having buyers remorse... what IF this is it?

    Problem found...
    My initial set-up was using the Denon AVR5700 Front Channel L/R Pre Amp outputs direct into to the MC2300. Now I suspect the AVR5700 Preamp output voltage is not linear (or logarithmic?) increasing with its volume control. So possibly it is not intended for direct connect to an AMP(?). I think a Pre amp out should be able to go direct into n AMP(?)...correct? Can anyone help shed some light on this? So this setup the sound level was loud but not audiophile quality when turned up. The MC2300 L/R channels were each peaking at 60WL/R (120W bridge). This really set me back, I figured the AVR5700 "Pre Amp" outputs should be able to drive the MC2300. So I have something to figure out or it just will not happen. Possibly I need to find some hidden configuration within the AVR menu and that could resolve? I did not find anything obvious to configure. So this weekend I integrated my Adcom GFP-555 Pre-Amp between the AVR5700 Front L/R Pre amp outs and the MC2300's mono inputs. I turned the ADCOM GFP-555 gain to 100%. I still use the AVR5700 remote volume control (Range -60...-50...-40...-30...-20... -10...0...10..15). The Adcom GFP-555 Pre-Amp intergration was the KEY to unlocking the MC2300 POWER POTENTIAL and with that said I have achieved with ease 600W into each L & R. That is an intermittent 600W burst when the source demanded it. Before I had to turn the AVR5700 up to -10...to get loud and not so ok audio. Now at modest -30...-20 AVR5700 volume settings feeding the Adcom GFA-555 with 100% gain, well that solved my problem.
    I got crazy a few times and turned it (AVR5700) way up to -10...0, just because I could and the systems sounded great so no concerns of clipping or THD, etc...
    YES!!!! 600W POWER was observed on the MC2300 meters, in accordance with MC2300 Meters range set to 0 and the needle reaching the 0 decibel marks (two meters, two marks each at W300+W300). Conclusion...When listing at this SPL (except for my wife) nothing in the system broke down...sonic clear clean fidelity throughout sub, mid, and tweeter frequencies. These MC2300 are the best audio investment I have ever made.

    As for the Polk Audio SDA 1Cs... the JAM session (8+hours) was a walk in the park for them. I had the front covers off and could see the drivers were so effortless in ROCKING & ROLLING.

    So in accordance with Mathew Polk the SDA 1C are rated 50-500W, I tested them to 500+W and they meet design spec. POWER, POWER, POWER... I am sold on POWER, POWER, POWER...

    And to top it all off Polk Audio just released a new flagship with SDA!
    Sweet timing for me, I will comfortabley keep investing in my vintage SDA.
    Next up... not listed in any particular planned order of implement.
    SL2000 replacements
    Crossover refurbishment.
    Avel 800V isolation transformer
    etc...the rest of the rabbit hole mods.....

    Thanks to everyone who has contributed to my quest of intergrating a GREAT AMP.

  • F1nut
    F1nut Posts: 50,622
    Ok, I'm confused. Why are you using an AVR and a pre-amp? I can't say I've heard of anyone doing that before.

    AVR's are not known for their pre-amp sections, so no surprise the sound quality suffered.

    One of the members here made enclosures for the Dreadnought, but I believe he is sold out.

    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 am unfortunately using the Adcom 555 pre-amp because of the AVR pre-amp.
    Like you said, ...are not known for their pre-amp sections.

    IF the Denon AVR5700 (1999 flagship) had good Pre-Amp outputs, then the system without the 555 would be Goldie Locks for DTS 5.1 and a few other medium that depend on the AVR5700 DSP. I was not that aware (lesson learned) of how bad it really is.

    I have since found the most recent Denon AVR8500H (2019 flagship) has channel assignable and clean Pre-Amp outputs. So possibly the AVR industry is starting to turn the corner from "commercial" home theater to an "audiophile" home theater products. Time & reviews will tell.

    So why stick with the Frankenstein AVR5700 Adcom 555 pre-amp integration...to get the best *stereo and **beyond... e.g. SACD Quadraphonic, SACD 5.1+LEF audio, DVD 5.1 audio, DTS 5.1+LFE audio, DTS 5.1+LFE home theater, DD 5.1 home theater etc...

    *Enables the full Stereo potential of the MC2300/SDAs.

    **4.0 & 5.1 Audio and Video
    FL/FR Polk Audio SDA 1C
    C Polk Audio CS20
    RL/RR Polk Audio 5JR+ for direct fire audio, DTS, DVD audio, SACD 5.1 etc...
    RL/RL Polk Audio LS/fx dipol/bipol for DD 5.1 home theater - set up as dipole
    L/R PSW300/PSW300 (auto on triggered by Stereo and/or 5.1 and/or LFE source(s) signals.

    **Enables integration of 2 (discrete L&R channel) Polk Audio PSW300 (125W) subs.
    The PSW300 each have three different source inputs,
    #1) input a 4K impedance input that Low Passes sub frequancy picked off of the FR/FL speaker wires,
    #2) RCA jack ".1" of 5.1 sources
    and
    #3) LFE (Low Frequency Effects) ER/EL inputs. I know Sub freq can not be heard in stereo. so why two? With two subs and listing to Stereo... I can not localize the sub source, so in effect it is enveloping sub vs. localized sub. Think of it like SDA evvelopment vs. localized sound, except for sub freq. And more folks in the room get to enjoy being seated in the sub sweet spot, or more appropriate plural spots. I have worked out the destructive (dB drop out) & constructive (dB increased SPL), so the CONS of two subs are resolved.

    There are many other reasons too...
  • F1nut
    F1nut Posts: 50,622
    I got a headache reading that, sorry. Seems to me there's too much stuff hooked together, but if you're happy.
    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

  • FraSerK
    FraSerK Posts: 16
    Hello F1nut et al,
    I discovered (rediscovered) a setting in my DenonAVR5700 that had 5.1 L&R front channels each attenuated by -6dB & .1 SUB was +3dB. This 5.1 setting impacted "stereo" too. I stumbled across these settings by fiddling with the remote control.
    I had set this up (circa 1999) because the SUB frequencies were just not being produced while watching Laser Disk AC3 Dolby Digital 5.1 movies.

    The -6dB was keeping the Denon PRE-AMP line out from achieving proper voltage level to drive the AMPs.

    So the Adcom was making up for that. I removed the ADCOM after finding and corrected for my "circa 1999" 5.1 L/R front -6dB SUB +3dB set up.
    All three channels were zeroed out. After this the Denon AVR5700 did a great job of driving the AMPS.

    However I ended up pulling the SDA 1C out of the 5.1 set up.
    Replaced the SDA 1C 5.1 front L/R with Polk Monotor 5 (not 5jr).

    The SDA 1C are now purely used for Stereo.
    And I purchased a NAD 1600 Pre-AMP that feeds the bridged McIntosh 2300 AMPS.

    I always knew something was wrong with the Right speaker mid's and high's.
    I just didn't known if it was the Denon AVR5700 or crossover CAPS.

    So I bought the NAD 1600 PRE_AMP. After that I knew it was the speaker crossover CAPs. So I rebuilt the Polk crossovers. While I was in there I also replaced the RES to MILLS, pulled the tweeter bypass cap (not pictured) and replaced the polyswitch with .17MILLs RES.

    That fixed the RIGHT speaker MID's and HIGH's and improved the overall L/R speakers audio performance. I don't have words in my vocabulary to describe sound, e.g. the MID's were warm like butter nut squash from the oven and let to rest for 45minutes.
    Simply put the SDA 1C sound amazing.

    The old original vs. new sonic CAPs didn't noticeably change the Left speakers frequency response, when measured with miniDSP and REW software. The new sonic CAPs defiantly FIXED the Right speakers MIDs and Tweeter frequencies, as shown by frequency response recorded by miniDSP and REW software.

    Both speakers sound amazing with new sonic gen 1 CAPS and MILLS RES, etc...

    Something the refurb did NOT effect was the delta in SUB freq. The Right speaker is considerable (-10dB from 20kHz ~ 50Hz) lower than the Left speaker, with both the old and new caps installed. I suspect this is due to speaker placement. The Left is in a room corner, about 3 feet from wall and 2 feet from back wall and right is 5 feet from a hallway wall (no corner) and 2 feet from back wall.
    Any other ideas on the SUB delta?


    md7gg8uy49dw.png
    3grg26t2qnni.png

  • F1nut
    F1nut Posts: 50,622
    Check for air leaks, do the PR push test.
    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

  • maingey
    maingey Posts: 632
    edited October 2019
    [quote="
    F1nut et al,
    I discovered (rediscovered) a setting in my DenonAVR5700 that had 5.1 L&R front channels each attenuated by -6dB & .1 SUB was +3dB. This 5.1 setting impacted "stereo" too. I stumbled across these settings by fiddling with the remote control.
    I had set this up (circa 1999) because the SUB frequencies were just not being produced while watching Laser Disk AC3 Dolby Digital 5.1 movies.

    The -6dB was keeping the Denon PRE-AMP line out from achieving proper voltage level to drive the AMPs.

    So the Adcom was making up for that. I removed the ADCOM after finding and corrected for my "circa 1999" 5.1 L/R front -6dB SUB +3dB set up.
    All three channels were zeroed out. After this the Denon AVR5700 did a great job of driving the AMPS.

    However I ended up pulling the SDA 1C out of the 5.1 set up.
    Replaced the SDA 1C 5.1 front L/R with Polk Monotor 5 (not 5jr).

    The SDA 1C are now purely used for Stereo.
    And I purchased a NAD 1600 Pre-AMP that feeds the bridged McIntosh 2300 AMPS.

    I always knew something was wrong with the Right speaker mid's and high's.
    I just didn't known if it was the Denon AVR5700 or crossover CAPS.

    So I bought the NAD 1600 PRE_AMP. After that I knew it was the speaker crossover CAPs. So I rebuilt the Polk crossovers. While I was in there I also replaced the RES to MILLS, pulled the tweeter bypass cap (not pictured) and replaced the polyswitch with .17MILLs RES.

    That fixed the RIGHT speaker MID's and HIGH's and improved the overall L/R speakers audio performance. I don't have words in my vocabulary to describe sound, e.g. the MID's were warm like butter nut squash from the oven and let to rest for 45minutes.
    Simply put the SDA 1C sound amazing.

    The old original vs. new sonic CAPs didn't noticeably change the Left speakers frequency response, when measured with miniDSP and REW software. The new sonic CAPs defiantly FIXED the Right speakers MIDs and Tweeter frequencies, as shown by frequency response recorded by miniDSP and REW software.

    Both speakers sound amazing with new sonic gen 1 CAPS and MILLS RES, etc...

    Something the refurb did NOT effect was the delta in SUB freq. The Right speaker is considerable (-10dB from 20kHz ~ 50Hz) lower than the Left speaker, with both the old and new caps installed. I suspect this is due to speaker placement. The Left is in a room corner, about 3 feet from wall and 2 feet from back wall and right is 5 feet from a hallway wall (no corner) and 2 feet from back wall.
    Any other ideas on the SUB delta?


    md7gg8uy49dw.png
    3grg26t2qnni.png

    [/quote]

  • vader540is
    vader540is Posts: 191
    edited June 2022
    FraSerK wrote: »
    now back to business...to reiterate I'm the original owner of SDA-1C & finally (30+yr) at the point I can afford a great AMP. What are some recommended 300-500+W AMPS that are compatible with the SDA 1C?


    IMHO its not all about how many watts you have.

    I have a Pair of SDA 1C and I use a NAD 2200 power envelope. It was refreshed by quirk audio.


    Here is a review of the Amp.

    https://www.audiosciencereview.com/forum/index.php?threads/nad-2200-vintage-amplifier-review.13960/

  • audioluvr
    audioluvr Posts: 5,592
    3 years later...
    Gustard X26 Pro DAC
    Belles 21A Pre modded with Mundorf Supreme caps
    B&K M200 Sonata monoblocks refreshed and upgraded
    Polk SDA 1C's modded / 1000Va Dreadnaught
    Wireworld Silver Eclipse IC's and speaker cables
    Harman Kardon T65C w/Grado Gold. (Don't laugh. It sounds great!)


    There is about a 5% genetic difference between apes and men …but that difference is the difference between throwing your own poo when you are annoyed …and Einstein, Shakespeare and Miss January. by Dr. Sardonicus
  • vader540is
    vader540is Posts: 191
    edited June 2022
    Wow lol im dumb.

    I always sort via " recent discussion"

    Not sure how I landed on this 3yr old thread lol