Crown CDi1000 Power Amp Review and Measurements - Stream of Consciousness

Discussion in 'Power Amps' started by purr1n, Jan 12, 2020.

  1. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Yeah. Maybe its Class H or G, with the variable power rails and traditional output.
     
  2. Psalmanazar

    Psalmanazar Most improved member; A+

    Pyrate Slaytanic Cliff Clavin
    Joined:
    Sep 27, 2015
    Likes Received:
    5,345
    Trophy Points:
    113
    Modded used workhorse pro amps and Adcoms have long been super bang for buck. The Adcoms MUST BE MODDED and the fans MUST be changed on many pro amps for domestic use in the same room.

    if anyone is a lazy piece of shit and doesn’t mod and complains, then they are a lazy piece of shit.
     
  3. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Should be fine with this newer Class D, H, G stuff. The fan(s) aren't audible and if the amps are pushed into hundreds of watts, the parts inside are going to sing louder than the fan! I'm sure most home speakers will melt by then. The older class AB amps with linear power supplies and big transformers, those fans can be loud at idle.
     
  4. Superexchanger

    Superexchanger Friend

    Pyrate
    Joined:
    Jul 11, 2019
    Likes Received:
    1,309
    Trophy Points:
    93
    Location:
    Flavortown, USA
    Is there any reason to expect that the benefits heard with the very efficient JBL's would extend to less efficient speakers with more complex crossovers?

    I'm intrigued by this as an option to push 87 dB / 8 ohm nominal floorstanders.
     
  5. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Of course. With less efficient speakers, stuff like this is ideal. This is where the incredible crazy power comes in handy. Even more so if the impedance drop low in certain spots. Unfortunately, I don't have any moderate or low efficiency speakers around.

    It's the really opposite of the Aegir, which I think would more ideally be suited to wide-banders (which never dip below 8-ohms) which never dip below 8-ohms and let a something else (like this for instance with its built-in DSP) power the subs.
     
  6. Superexchanger

    Superexchanger Friend

    Pyrate
    Joined:
    Jul 11, 2019
    Likes Received:
    1,309
    Trophy Points:
    93
    Location:
    Flavortown, USA
    Ah. Reading the comments before about synergy with high-efficiency speakers made me wonder if there were rules of thumb I wasn't aware of.

    I'm generally looking to be punched in the face by the sound produced by my 2-channel setup, on the cheap, so this really looks like it's worth a try. Thanks for bringing awareness about options like this.
     
  7. Armaegis

    Armaegis Friend

    Pyrate BWC
    Joined:
    Sep 27, 2015
    Likes Received:
    7,464
    Trophy Points:
    113
    Location:
    Winnipeg
    Maybe it's just the Canadian part of me, but I still like Bryston amps. They've suffered from price creep because they still try to do everything in Canada and that suuuuuucks because the manufacturing isn't cheap here. It's even worse on their digital products because getting all the required certifications up here is ugly-cry expensive.

    On the used market, I think their amps are still good bang for the buck. I had a tri-amped stack with a 4B/3B/2B (actually two 2B's bridged into mono for each side) that was a lot of fun. Ultimately I took it apart, because my rack was not meant for that kind of weight. Bryston's 20-year warranty is also nothing to scoff at. I've had fantastic service from them sending in amps for checkups (not the original owner on any of them), upgrading components for cheaper than I could have done on my own, and just great communications throughout the process.

    The class G and H stuff isn't a variant on class D. It's a variant on class A/B where the power rails modulate higher during peaks of music so you don't have as much wasted energy. G has multiple rails, while H actively varies the rail just ahead of the peak (I might have G/H swapped, I don't remember).
     
  8. Armaegis

    Armaegis Friend

    Pyrate BWC
    Joined:
    Sep 27, 2015
    Likes Received:
    7,464
    Trophy Points:
    113
    Location:
    Winnipeg
    More power is *usually* desirable, but after a certain point more power comes at a price. Either literally more $$, more gain/noise, larger physical size/weight, or sonic sacrifices to get the kilowatts, etc. Get as much power as you need for a more-than-comfortable-amount of headroom, and call it a day.
     
  9. MrTie

    MrTie Friend

    Pyrate
    Joined:
    Sep 30, 2015
    Likes Received:
    815
    Trophy Points:
    93
    Location:
    A.B.E. - PA
    @purr1n I used them for a time with pair of a old B&W DM3000's and also as Crossover/DSP/Amps for a two way horn system using klipsch K402/La Scala bass horn. Neither actually super bright systems. They were not terrible on the B&W, but certainly worse sounding than the nCore 500s I had later. That's why I'm assuming they have improved the design, even the Drivecores sounded better to me when they first came out.
     
  10. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    The new version of the XTi is the XTi1002 right? Might will pick one up and compare to CDi1000 to make sure they sound the same. The binding posts and XLR would certainly be easier to deal with.
     
  11. ogodei

    ogodei MOT: Austin AudioWorks

    Pyrate
    Joined:
    Feb 9, 2016
    Likes Received:
    2,764
    Trophy Points:
    93
    Location:
    Chicago
    Used CDi1000 is available for $200 + $8 for two adapters from Sweetwater.

    Used XTi1002 is $450

    I can deal with fiddly wires for 240 bucks
     
  12. MrTie

    MrTie Friend

    Pyrate
    Joined:
    Sep 30, 2015
    Likes Received:
    815
    Trophy Points:
    93
    Location:
    A.B.E. - PA
    Yes that's correct. No clue why the Xti1002 are so expensive used.
     
  13. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Indeed. I bought the CDi1000 for less than used XTi1002 prices. I would surmise it's the ease-of-use factors. Most people won't want to deal with Phoenix / euroblock and terminal strips.
     
  14. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Get this amp and a used passive Dynaudio. Most will come in active configuration, but if you can find something like a used passive BM15 with the 10" woofer or X16 with the 7" woofer, you will definitely be good to go. They aren't the most efficient, but they will take a ton of power and react accordingly - that is punch you in the face. Expect to pay $800-$1000 for the speakers.
     
    Last edited: Jan 14, 2020
  15. JayNYC

    JayNYC Friend

    Pyrate Contributor
    Joined:
    Jun 10, 2016
    Likes Received:
    39
    Trophy Points:
    18
    Location:
    Miami Beach, FL
    On the Crutchfield product page for the CDi 1000, the fourth bullet under Product highlights suggests Output eq is not bypassable

    https://www.crutchfield.com/p_859CDI1000/Crown-CDi-1000.html

    “output EQ: 8 parametric filters per channel with adjustable Q, ±15 dB boost/cut, and adjustable shelving filters (not bypassable)”
     
  16. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    The front panel has a DSP bypass. I think Crown is saying that once DSP is on, the 8 PEQ bands are always there are cannot be selectively bypassed, like on dedicated digital EQ boxes.
     
    Last edited: Jan 15, 2020
  17. Priidik

    Priidik MOT: Estelon

    Pyrate BWC
    Joined:
    Sep 27, 2015
    Likes Received:
    2,153
    Trophy Points:
    113
    Location:
    Estonia
    Looks to me like a typical AB with some CM coils to relieve from the sins of the switcher before it, (probably also G/H at higher demand), probably mosfets for such power in so few parts count.
    I'm surprised to see TO-3 (still the best casing for thermals) parts in so recent design. Can you read the dev name or get a close up?
     
    Last edited: Jan 15, 2020
  18. Priidik

    Priidik MOT: Estelon

    Pyrate BWC
    Joined:
    Sep 27, 2015
    Likes Received:
    2,153
    Trophy Points:
    113
    Location:
    Estonia
    I admire your courage. This resistor without heatsink would be around 60W rated.
    Short term it can take 10x more and it will take a while to burn it down.
    I burned hole into a desk with a 100W unit without heatsink and it was in spec afterwards.
     
  19. Psalmanazar

    Psalmanazar Most improved member; A+

    Pyrate Slaytanic Cliff Clavin
    Joined:
    Sep 27, 2015
    Likes Received:
    5,345
    Trophy Points:
    113
    Those are great. The passive Dynaudios designed by Andy Munroe are pretty much indestructible. The active plateamps have had some durability issues and were cheaped out after the initial (and still available) BM15 a and BM6a. Too bad Dyn went downhill in the 2000s. I heard the Lyds and went WTF
     
  20. purr1n

    purr1n Desire for betterer is endless.

    Staff Member Pyrate BWC
    Joined:
    Sep 24, 2015
    Likes Received:
    89,775
    Trophy Points:
    113
    Location:
    Padre Island CC TX
    Doesn't seem a problem with quick few second bursts (enough to get a good FFT) such as the THD+N vs voltage level plots, but sustained more than a few seconds at 375W, those things get mighty hot. Might need to build something mounted to fireproof plate with fans. I figure I'll take a voltage reading at lower wattage to confirm, and then to do the math from there.

    upload_2020-1-15_11-9-59.png
    upload_2020-1-15_11-10-35.png

    MJ21194G for the NPN
    MJ21193G for the PNP

    BJT.

    http://www.farnell.com/datasheets/1...XID2Y9mkpSAQToAVpnF8xoIsUQ_j1F1caAttJEALw_wcB

    They sure will take a ton of voltage. Could be fun to put these direct coupled after a tube and add a big cap after the transistors for a headphone amp. Sort of a tube / transistor hybrid OTL. Haha.
     

Share This Page