Superb AVM-20 Upgrade

Discussion in 'AV Receivers' started by Eduard_M, Jul 2, 2003.

  1. Eduard_M

    Eduard_M Auditioning

    Joined:
    Jun 3, 2003
    Messages:
    3
    Likes Received:
    0
    I have used the AVM-20 (ver 2.0) for over one year in a combined audio/video set up. I have been totally happy with it's processor, usability and general sound reproduction and incredible flexibility (replaced EAD Ovation). While in contact with Chris Johnson of Partsconnexion (www.partsconnexion.com), about upgrading my Sony DVP-S9000Es, I asked about upgrading the analogue portion of the AVM-20. Primarily, I was looking for better resolution out of the CD input for CD& SACD. In short, the upgrade involved soundcoat dampening material, replacing op amps, capacitors, resistors etc. that affected the main pair of balanced outputs and the 1 pair of RCA analogue input marked 'CD'.
    This upgrade has totally elavated the performance of the AVM-20 as a pre-amp. Improvements affect cd, sacd and dvd performance. The soundstage is slightly larger with more depth and better focus. The timber of the various instruments are much more apparent (plucking of strings, richer tone, deeper bass, smoother violins, more relaxed sound, decay of piano etc.). More air around the various instruments and better pace. The most notable improvement is in the cd playback quality. Without changing anything else, the steely, gritty sound has all but disappeared (yes SACD is still superior). The same audible improvements are positively heard from music dvds and movies in general, especially those with well recorded soundtracks. Watching the Haunting again, there was so much more detail resulting in an even greater totally involving experience. I will be experimenting with different power cords (currently using XLO 10g), to squeeze some additional improvements. This is getting a little too long, but I wanted to share the dramatic improvement a cost effective upgrade can bring to what you already own. I now have a high-end pre-amp that also does home theatre with multi-zone capabilities. Who says you can't have it all. Thanks. Ed
    ps The rest of the system is a Blue Circle BC32 (6 channel amp, also supperb), Mirage OM7, OM-R2 & OM200. Cabling is Harmonic Tech. Pro-Silway II interconnects and Pro 9 speaker cable.
     
  2. Michael Mohrmann

    Michael Mohrmann Screenwriter

    Joined:
    Dec 30, 2001
    Messages:
    1,394
    Likes Received:
    0
    Sounds like an upgrade to Anthem's D1 processor. Well, one without the extra Motorola processor and valid warranty, that is! [​IMG]

    So, what was the cost of the upgrade? Did you perform the modifications yourself?

    Michael
     
  3. Eduard_M

    Eduard_M Auditioning

    Joined:
    Jun 3, 2003
    Messages:
    3
    Likes Received:
    0
    Michael,
    I'm not familiar with the sound of the D1, so I can't comment. The upgrade was done at the partsconnexion lab, and it took them about 4 days plus shipping. Only the analogue path was upgraded and not the digital. I got a bit of a break on the price, as my unit was the first. Suggest you contact Chris directly if you are interested. I certainly found the difference worth every penny even without any discount. This has made one of the largest differences in my system.
     
  4. Doug_B

    Doug_B Screenwriter

    Joined:
    Feb 11, 2001
    Messages:
    1,081
    Likes Received:
    0
    Eduard,

    So if I understand this correctly, they performed changes to some portion of the input path for one set of analog inputs and some portion of the analog output path (minimally the balanced outputs for the main L/R channels). As such, any form of audio input, no matter how processed by the AVM 20 (analog direct, analog DSP, digital in) should be impacted if the L/R balanced outputs are used, and add'l impacts would apply to any source connected to the CD analog L/R inputs. Interesting.

    So is there the same level of improvement in SACD as there is in redbook CD, assuming you've tried SACD in 2 channel? Have you also fed the upgraded CD input with SACD? In general, how much of the overall improvement is associated with the CD input changes versus the balanced L/R output changes? Have you tried all the relevant analog combos (let's assume just in analog bypass mode to keep it simple): CD-to-balanced, CD-to-unbalanced, nonCD-to-balanced, and nonCD-to-unbalanced?

    I'm curious if there is any change noticed for the RCA L/R outputs as well, as it's possible that some of their changes may have had such impacts (e.g., out of necessity because certain components changed could be shared for both forms of output).

    Thanks.

    Doug
     
  5. Eduard_M

    Eduard_M Auditioning

    Joined:
    Jun 3, 2003
    Messages:
    3
    Likes Received:
    0
    Hi Doug,
    The main surgery was on the main channel L&R balanced outputs. According to Chris, because of the design, by upgrading the balanced main outputs, the center channel and RCA mains/center also get the same benefit. I don't use the center channel, so I can't verify. As a secondary option, I also asked that the 'Cd' input be upgraded as much as possible. My source is the Sony DVP-S9000ES which I use for stereo cd and stereo sacd, using the player's analogue output.
    You are correct in that it's the main outputs that improves the sound of every source significantly. For DVD music/movies, I use the digital input. For cd/SACd, I use the improved analogue 'cd' input (same input)in analogue direct/bypass mode. Using identical RCA cables from the Sony's two analogue outputs, I was able to do an A/B and compare the improved cd input to a standard one. There is a marginal improvement on the upgraded one (a little richer, more open and less edge), however, the biggest difference is due to the main outputs. SACD still sounds the best. I guess the thing that floored me was how much more tolerable the red book cd now sounds. So bottom line is that all sources (cd, sacd, dvd) whether from analogue or digital have greatly improved.
     
  6. Doug_B

    Doug_B Screenwriter

    Joined:
    Feb 11, 2001
    Messages:
    1,081
    Likes Received:
    0
    Eduard,

    Thanks for the feedback. As I have been pondering trying out a 2 ch pre-amp (probably tube-based) for my music, thus bypassing the AVM 20, this upgrade presents another possible alternative, and one that would not require adding yet another shelf to my rack. My primary concern would be if I needed warranty service on the unit.

    Good luck with the upgrade.

    Doug
     

Share This Page