1st gen SDA CRS question

Hi all,

New to this forum and glad to have found it. Bought these new in the mid-80s - the model with dual tweeters. Enjoyed them from then until a move in 2007. Recently got them back out, along with my turntable, and have been having a blast in my small (12x15) new listening room.

My question is, do I have enough amplifier to get the most out of these in an apartment environment? Currently using a Yamaha R-90 with 75 wpc into 8 ohms. I think the speakers are actually about 6.5 ohms. I don't really have any complaints, but have read that "you really need 200 wpc with these speakers" (using know-it-all voice).

Thanks for your thoughts and advice!
«1

Comments

  • F1nut
    F1nut Posts: 49,707
    edited March 2018
    You do NOT need 200wpc to get the best out of those speakers. What you do need is a high current power source and your receiver isn't one. Look for a nice integrated amp or separate pre amp/amp.

    BTW, all watts are not created equal. There are low powered amps that will put to shame higher powered ones and vice versa.
    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

  • FestYboy
    FestYboy Posts: 3,861
    F1nut wrote: »
    BTW, all watts are not created equal. There are low powered amps that will put to shame higher powered ones and vice versa.

    Early NAD is a good example ;)
  • Dr_Wu
    Dr_Wu Posts: 305
    Thanks guys. Would a B&K AVR-505 fit the bill?
  • F1nut
    F1nut Posts: 49,707
    You want a 2 channel integrated or separates.
    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

  • audioluvr
    audioluvr Posts: 5,420
    edited March 2018
    Dr_Wu wrote: »
    Thanks guys. Would a B&K AVR-505 fit the bill?

    Yes. Im using the Reference 50 pre for my 2 ch audio. Very good DAC. Should be a significant upgrade from the Yamaha
    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
  • Dr_Wu
    Dr_Wu Posts: 305
    Still deciding what to do about better power for the SDA-CRS. To be used for vinyl and CD.

    I'm looking at a vintage Denon PMA-520. Any thoughts?
  • Legender
    Legender Posts: 478
    You could try it... plenty of those online for about $50... but really think you want something more capable and known to work well with the older Polk speakers. Parasound comes to mind...
    Sounds like you don't want to spend over $100 on an amp...
    Music: Oppo103 - Parasound JC2 - Parasound A21- SDA 3.1
    Theater: Denon 3808 - B&K 7500/Emotiva XPA-3- RTi12, CSi5, RTiA7x4, PSW505
    Sleeping: Marantz 70005 - Harman Kardon 2400 - SDA 2
    2 Channel: Cary 306 SACD - Canary Audio 906 - Pass Labs x250 - PS Audio Perfectwave DAC, Polk LSiM705, SVS SB13 Ultra
    Office: Dell Optiplex, Emotiva XDA-2, Adcom 5500, LSiM 703
    Spares: Yamaha CA-810; LSi 15; Kenwood Basic M2a, Yamaha M60/M80, Polk Monitor 7, SVS SB13 Ultra
  • Dr_Wu
    Dr_Wu Posts: 305
    Thank you. Not necessarily. It's more that you're the first person to suggest a particular brand as being a good fit with the Polks. And, I appreciate it and will look into it.
  • Tony M
    Tony M Posts: 11,009
    Older big onkyo receivers might get you buy. I can't recommend Onkyo separates anymore.

    Good luck finding an affordable power source. there's been some great recommendations already. Check your local area.
    Most people just listen to music and watch movies. I EXPERIENCE them.
  • xschop
    xschop Posts: 4,636
    I can highly recommend the early Onkyo Integra integrated amps for the CRS. They handle the 4 ohm load without struggling and put out beautifully balanced sound.
    Don't take experimental gene therapies from known eugenicists.
  • Dr_Wu
    Dr_Wu Posts: 305
    Appreciate that, xschop!
  • Msabot1
    Msabot1 Posts: 2,098
    If ya can find one in decent shape,those old Onkyo M502 amps should fit the bill..Can be had these days for not a whole lot of coin...
  • motorstereo
    motorstereo Posts: 2,042
    Msabot1 wrote: »
    If ya can find one in decent shape,those old Onkyo M502 amps should fit the bill..Can be had these days for not a whole lot of coin...

    Agreed; I had an Onkyo M508 and it was an excellent match up for my non plus CRS's.
  • Msabot1
    Msabot1 Posts: 2,098
    Msabot1 wrote: »
    If ya can find one in decent shape,those old Onkyo M502 amps should fit the bill..Can be had these days for not a whole lot of coin...

    Agreed; I had an Onkyo M508 and it was an excellent match up for my non plus CRS's.

    Yea..I have a M504 in the mix...punchy amp..If you can find any of the M series power amps..grab it...
  • Dr_Wu
    Dr_Wu Posts: 305
    You guys are great! Thank you.
  • xschop
    xschop Posts: 4,636
    I scored the Integra I was originally looking for to rebuild (A-8190), but after updating/modding the A-8017, It has PLENTY of power....

    https://www.hifiengine.com/manual_library/onkyo/a-8190.shtml
    Don't take experimental gene therapies from known eugenicists.
  • Dr_Wu
    Dr_Wu Posts: 305
    Msabot1 wrote: »
    Msabot1 wrote: »
    If ya can find one in decent shape,those old Onkyo M502 amps should fit the bill..Can be had these days for not a whole lot of coin...

    Agreed; I had an Onkyo M508 and it was an excellent match up for my non plus CRS's.

    Yea..I have a M504 in the mix...punchy amp..If you can find any of the M series power amps..grab it...

    I have found an Onkyo M-501. The amp says its for 8 Ohm minimum speakers. I think the SDA-CRS are rated at 8, but the SDA Handbook says the nominal impedance is 6. Would this amp be a problem? Thanks.
  • Msabot1
    Msabot1 Posts: 2,098
    Those M series are all high current...common ground and can handle 4ohm loads..plus they are music machines..built to last..About the only difference in the models is RMS output wattage...
  • Dr_Wu
    Dr_Wu Posts: 305
    Thank you! Any idea what they're worth? Looking at a very clean one.
  • Msabot1
    Msabot1 Posts: 2,098
    I got my 504 for around four bills.. That was maybe four years ago..It had all the test results from the shop where I found it and looked right out of the box new..That was here so I don't know how the market is in your area...
  • Tony M
    Tony M Posts: 11,009
    edited April 2018
    I paid 400.00 and 250.00 for 2-504's. BOTH died in a years time sitting on the shelf. The power-up relay switches I think.

    I also bought a 502 around the same time. It died in a years time too, sitting on a shelf. The power-up relay I think.

    I still have both of them for some reason. Maybe a qualified great technician can get them both going again.
    Most people just listen to music and watch movies. I EXPERIENCE them.
  • Dr_Wu
    Dr_Wu Posts: 305
    Hmm. A Tale of Two Amps. "It was the best of times . . ."
  • Tony M
    Tony M Posts: 11,009
    edited April 2018
    A lot of members agree with that Title and leading sentence for sure. ;):pB)

    And Dave would have to say; A Tale of One AMP. "It was the worst of times". :s Sorry, Dave. :'(:)
    Most people just listen to music and watch movies. I EXPERIENCE them.
  • Schurkey
    Schurkey Posts: 2,100
    edited May 2018
    Dr_Wu wrote: »
    I have found an Onkyo M-501. The amp says its for 8 Ohm minimum speakers. I think the SDA-CRS are rated at 8, but the SDA Handbook says the nominal impedance is 6. Would this amp be a problem? Thanks.
    I had no idea that the 501 wouldn't support 4-ohm speakers. I had to download the service manual to verify.

    I thought the 501 was well-regarded. Pity.

    There's usually three reasons an amp won't be rated for 4 ohms.
    1. Not enough output devices to handle the current
    2. Not enough heat sink to handle the heat of all that current, including the heat of the FCC 1/3 power for 1 hour preconditioning.
    3. Not enough power supply to provide all that current.

    (or some combination)

    I wonder what's lacking in the Oinkyou.

    Yamaha is big on installing a switch on the back panel for "low impedance" use. The switch strangles the power supply, to prevent full voltage from getting to the + and - rails, which prevents cooking the amp due to "high current".
  • Yamaha is still in business making decent to really good stuff. Many have either gone the cheap route or out of business.
    Yamaha RXA1030, Yamaha CD-S2100, Yamaha AS-2200, Bluesound node 2i
    Polk SDA2btl highly modded
    Polk SDA 1C modded
    Polk CS350 LS x2
    Kimber 8TC
    Sony 55" Bravia
    Wish list SVS sub

  • Schurkey
    Schurkey Posts: 2,100
    Yamaha is still in business making decent to really good stuff. Many have either gone the cheap route or out of business.
    Yamaha ain't what you think anymore. A person has to spend a pile of money to get an FTC 4-ohm-capable unit.

    The A-S801 ($900) is the top-of-it's-line unit, and still isn't FTC rated for 4-ohm loads. Has the dreaded "strangulation switch" on the back panel.
    The A-S1000 ($1800) is FTC rated for 4-ohms, and is the lowest-price true 4-ohm amp I see on the Yammie web site. Maybe I missed something...but I don't think so.

    Yamaha is playing games with "Maximum Power" or "Maximum Effective Power" ratings that include TEN PERCENT THD!!! They're not to be taken seriously any more when they stoop to that crap.
  • Dr_Wu
    Dr_Wu Posts: 305
    Can anyone tell me how the SDA-CRS speakers will "go with" the Mac754 and vintage Yamaha receiver/pre-amp? Thanks.
  • Dr_Wu
    Dr_Wu Posts: 305
    Hope it's OK to use this thread to continue my explorations and advice-seeking.

    I've picked up a Sonamp 275se: 75wpc @8ohms; 125 @4ohms) that I hope to hook up to a vintage Yamaha receiver (CR-400) that I want to try as a preamp. Can't wait to hear if this improves the sound of my Polk SDA-CRS speakers (1984-86 version, with (2) SL-1000 tweeters, fuses, blade/blade connectors). Also use a powered sub, and bought some nice new cables and ICs. Until now, I've only used receivers to drive them: Yamaha R-90 or Pioneer AV (70 and 105 wpc, respectively).

    I've now set up a small strictly 2-channel music room, 12'x15', in an apartment building (fortunately no common walls with other units, though my days of "cranking it" are well-behind me). The Polks are set up on the long wall and, as directed, have 3' of space on both ends, 4' between the inside edges, and listening area 5' away and between the speakers. Sources are CD and vintage Dual TT (1019) with nice cart (AT12sa w/ Shibata stylus).

    It will probably surprise no one here that I'm already thinking about renewing/upgrading my speakers, or dare I say it, buying some new tech bookshelf speakers. Don't misunderstand. I've loved the Polks since the moment I first heard them. Bought them on the spot. Most expensive audio purchase I'd made at the time. What I still enjoy about these all original/fully functioning speakers is well-known to you: the breadth and depth of the soundstage. Still, I can't help wondering how much better it might be? I know, it's a sickness.

    So, here are my questions/thoughts/issues: Update/upgrade the CRS? RD-0194 tweeters? Crossovers? At what cost? Will that get me as good, if not better sound than something new (like Elac UB5s, MartinLogan Motion 15LX, Dali Spektor 2, or maybe SVS Ultra).

    Anyone else been in this position? As always, I appreciate your suggestions. Thanks.
  • Dr_Wu
    Dr_Wu Posts: 305
    edited June 2018
    So, I got a vintage Yamaha receiver back after a good cleanup (Thanks! Vinyl Groove), and hooked up the amp. After some input level tweaking and balancing, I'm experiencing the soundstage produced by the CRS speakers in a whole 'nother way. I thought they were good before . . what took me so long?! Doh! Of course, now I'm thinking: preamp?

    Anyway, just in time for delivery of 3 sets of new bookshelf speakers for an A v B v C v D experiment. The new stuff is going to have to really step up to beat the home team.
  • FestYboy
    FestYboy Posts: 3,861
    It's gonna be hard to beat the CRS...