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Avondale SE200 Announcement on FB

Discussion in 'd.i.y.' started by Richard Lines, Jul 29, 2022.

  1. Richard Lines

    Richard Lines pfm Member

    Good Morning All,

    I was a little surprised to read LesW's announcement on Facebook from the 27th re the SE200 series devices as a very recent communication had suggested these were on the back burner.

    I have been requested to remain silent about the boards I've been working with recently, although just before his recent hospital treatment LesW had indicated I could divulge things in a considered way as he didn't want a deluge of enquiries at that time.

    What can I say about the prototypes to the SE200? Let's just say I'm no longer looking to further anymore NCC200, NCC220 or NCC300 builds.

    The NCC boards are definitely a step up from the Naim RCA pattern equipment but the SE boards are in a truly different ball park.

    It is these boards causing me to get the NAXO serviced and an old Hicap TPR'd to allow me to actively drive the Sara9's with 4off SE boards. As I have said I'm only driving the amplifiers out of a MacBook headphone socket - God alone knows what they'd sound like out of the Klimax System Hub (if only it had an analogue output).

    If I can get the 3rd pair up and running (stupidly installed 47k rather then 47R SMD's in the LTP emitter tails) I could drive my conventional Isobariks via the ExactBox.

    Regards

    Richard
     
    Last edited: Jul 29, 2022
  2. Mike Hanson

    Mike Hanson Lovely!

    As you know, Richard, I've got 4 of the alpha boards part way into amps, but my schedule has made it tough to finish up. I was going to make some progress next week, but I just started building myself a new work PC. :rolleyes:
     
  3. Arkless Electronics

    Arkless Electronics Trade: Amp design and repairs.

    OK so what is this new amp then?
     
  4. nuit73

    nuit73 nuit73

    Mike Hanson likes this.
  5. Arkless Electronics

    Arkless Electronics Trade: Amp design and repairs.

    I'm not on any social meja.
     
    Mynamemynaim likes this.
  6. nuit73

    nuit73 nuit73

    Some friends of Les test the board.
    They all say the audio result is outstanding!
     
    Richard Lines likes this.
  7. OldSkool

    OldSkool pfm Member

    I saw this on FB too but was a little confused about the difference between the SE200 and the SE230 (and SE400) already announced.
    I'M guessing the "SE" part means they're all from the same family topology, the 400 uses 8 output devices in total per channel/board and the SE230 uses 4 per channel/board. So what about the SE200, if the number represents power into 4R then it must be 4 transistors too (?).
     
  8. nuit73

    nuit73 nuit73

    The 400 is like the 300 (with a new schematic) and have in board regulator
    The SE 200 or 230 (variation, i hope), without in board regulator, is a drop in replacement for classic Naim amp board with the same ushape

    The more important is the guy (they have an old expérience of Nap board and NCC 200, 220 and 300), they all say the new amp board of Les is the finest of all !
     
  9. bugbear

    bugbear pfm Member

    Given Les's "Complimentary long tail pairs using current mirrors" statement, it sounds like he's gone for a fully symmetric input stage;

    Description of this circuit approach from Rod Elliott

    https://sound-au.com/amp_design.htm#s11

    BugBear
     
    Mike Hanson likes this.
  10. OzBrit Audio

    OzBrit Audio pfm Member

    All

    There is a picture of the SE200's installed in a NAP250 on Avondales Facebook page, latest posting.

    Looks different in every way from Les's previous offerings. I don't see enough in the front end for complementary long tails pairs with current mirrors, they are all BC546 transistors and not enough of them. Note a trim pot for DC offset which is nice. Also the front end gets new power supply filtering. No emitter resistors on the output which goes against the grain for low distortion. All very interesting

    As he sais, a completely new design. Be interesting to get more feedback on how good it sounds but I have no reason to doubt his initial write up.
     
  11. S-Man

    S-Man Kinkless Tetrode Admirer

    I suspect he has put SM emitter resistors under the PCB.

    I would have thought there would be a few BC556s in there.

    Cascodes?
     
  12. Richard Lines

    Richard Lines pfm Member

    I think you'll find that the 2off TO-220 devices will be the (non-inductive) emitter resistors??

    The SE230 boards do seem to be devoid of emitter resistors so one assumes they would be SMD devices mounted on the rear??? You'll see rectangles in the lower part of the board indicating other SMD components - the current mirror parts can be seen here (photo taken from the Avondale site).

    [​IMG]

    Regards

    Richard
     
  13. sq225917

    sq225917 Bit of this, bit of that

    I'll tell you what whoever soldered those deserves a bloody medal, those solder joints are perfection, lovely big, shiny, fully wetted joints.

    All apart from the lower leg on that 125 styrene cap. Which i suspect is nicely done underneath to leave space for the pliers that were used to wick the heat off the leg on the top of the board as it was soldered, just bloody lovely.
     
    John R, Svein, 337alant and 2 others like this.
  14. chiily

    chiily PFM Special Builder

    Through plated PCBs FTW. Something so satisfying about a mound of solder on top as well as underneath the PCB.
     
    sq225917 likes this.
  15. OzBrit Audio

    OzBrit Audio pfm Member

    No I don't think so, all BC546, 5 of them I think. Check out the pic on Les's Facebook (sorry couldn't work out how to cut and paste on here - insert URL didn't seem to work for me)

    Richard, stupid me - yes different format emitter resistors

    And Richard care to comment on how these boards sound compared with say the well regarded NCC300's (assuming you've have the latter)?

    Cheers
     
  16. Richard Lines

    Richard Lines pfm Member

    Having a pair of Isobariks which require 10 channels of amplification when the first pair of SE boards arrived I didn't really have a means of trialling them. I did have a pair of Sara9's though so they got dragged out and kind of just plonked in the Hi-Fi Room inboard of the Isobariks without any attempt at Tune Dem.

    I played Nils Lofgren's 'Keith Don't Go (Live)' and it was one of those 'jaw dropping' moments in life where you just stare blankly and think "Where the f**k did that come from?" I have played my stereo NCC200 Voyager, a pair of NCC220 M130's and my stereo NCC300 amplifiers into the same speakers and they are, quite simply, not in the same league, that is not to say they are bad just beaten in this instance.

    Bear in mind the source is 'only', the headphone out socket of an M1 MacBook Pro as there is no analogue output from the Klimax System Hub............

    I am very much wanting to get a pair of SE230's when they become available.

    Regards

    Richard
     
    Last edited: Aug 27, 2022
  17. andrewsutton

    andrewsutton pfm Member

    I can confirm the quality of the new thicker through plated SE double sided boards. Very solder hungry!
    The SE 230s are still being fine tuned so not ready yet.
    The older SE200s I have are certainly better than the Qudos boards but as mine are bodged onto a Qudos mono block with far from ideal wiring I can only assume that they will improve when the Qudos boards come out and the SE boards go in.
    The TO-220 devices are resistors and are zero inductance as best as my Peak analyser can measure.
    Cheers Andy.
     
  18. S-Man

    S-Man Kinkless Tetrode Admirer

    I think I'm looking at the wrong pics, I haven't seen an SE200 pic.
    On the SE230 pic Richard posted above there are 8 front end transistors. TR1-4 and Tr5-8 are probably opposite sexes.

    I do like the smaller footprint (NCC300 boards are quite hard to build into a compact amp) and Les does know how to make the board look pretty!
     
  19. Richard Lines

    Richard Lines pfm Member

    The photo's are up on the Avondale FB page:-

    [​IMG]

    Regards

    Richard
     
    John R, 337alant and wow&flutter like this.
  20. S-Man

    S-Man Kinkless Tetrode Admirer

    Thanks Richard.
    I don't do FB or the likes.
     

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