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Vintage audio integrations and upgrades

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  • Carver M-500(t) mkII Restore and Upgrade

       (4 reviews)

    This service is a full restoration and upgrade which includes cleaning inside and out, replacement of all consumable parts, reflow of questionable solder, service bulletins, new LEDs (your choice of color) for the meters, new 5-way binding posts, high-quality output relay, and the mkII upgraded components. This mod gives your 500(t) a much higher power rating, more headroom, less commutation distortion, better current sourcing and performance into low impedance loads, and tighter bass and transient control.

    We are the only techs authorized to perform this mod. Any other 'pros' out there claiming they can do this upgrade have copied information available on our websites and perform these upgrades without our permission.

    Our prices are well worth every penny. We stand behind our work 100%. If we can impress Bob Carver himself with our work, you can't be disappointed!




    How they look when we get them:



    How they look when we're done:





    - Long life high temp capacitors throughout

    - High performance audio grade capacitors in signal paths

    - Replace all power rectifiers and power switching diodes

    - Replace voltage trim pots

    - Replace entire pre-drive stage transistors to higher voltage, higher power type

    - Replace input opamp buffer to audio grade device

    - Replace output protection relay

    - Completely upgrade and rebuild output stage transistors for more linearity, durability and higher power handling

    - Replace meter bulbs with LEDs of your color choice

    - Upgrade speaker binding posts to modern 5-way gold or silver

    - Perform factory service bulletins where needed

    - Calibrate, burn-in and test to mkII specs. I also listen to all the amps I work on. It doesn't leave my bench unless is sounds like it should.

    - m500 models are upgraded with the 't' mod, as recommended by the factory.

    Comes with a 3-year warranty and lifetime waver of bench fees.



    Power into 8 ohms:
    Stock: 251 watts  
    MKII: 395 watts 

    Clipping into 8 ohms:
    Stock: 270 watts
    MKII: 410 watts

    Dynamic into 8 ohms:
    Stock: 380
    MKII: 520 watts


    LED options:

    Warm White:







    Cool White:





    All new power output transistors for high linearity and power handling:



    Binding Posts (gold shown) and optional IEC socket




    Although the Dim Switch will still dim the LEDs, The LED driver can be trimmed to your brightness preferences (Driver model 002 shown):





    mkII upgrade and restore Cost: $470 (includes Gold speaker binding posts, 3 year parts and labor warranty and full cleaning) + shipping.



    IEC socket: $40.00

    M500 power switch (added to back of unit): $40

    Other Options:

    Restore without mkII upgrade (stock specs, new LEDs): $350.00 + shipping

    Restore with new binding posts: $395.00 + shipping

    • Like 2

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    I came across a M-500 a couple years ago.  The amp was in cold storage for around 18 years.  I plugged it in and it worked but I could tell it needed service.  I did my research and boy did I get lucky when I came across Greg's number.  I sent the unit out to him and paid for as many upgrades as possible, including getting rid of the cheap power cord and replacing it with an IEC.  I used to sell Carver in the 80's so I'm very familiar with the amps and pre-amps.  This M-500 sounds SO awesome after Greg did what he does.  Greg also stands by his work.  A few months ago I had an issue with the right channel.  I called Greg and he sent me a shipping label.  He said send it back and I'll take care of it.  Couple weeks later I hooked it up and I've been listening to it ever since.  Keep up the good, sorry, great work!


    • Like 1
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    Years ago I had borrowed my brother's 2 Carver M500t amps with the MKII upgrade (done by Nelion Audio).  I absolutely loved the sweet, powerful sound they put out so recently I purchased 2 Carver M500t amplifiers online with the sole purpose of getting both upgraded to the MKII mod.  When I received the amps I verified they worked and immediately sent them directly to Nelion for the upgrade.   When the upgrade was complete I picked up my amps and installed them in a bridged configuration (1 per channel) in my den.  Now I cannot listen to my new system without a smile on my face.  The mod is well worth the price and the quality is top notch.  I wouldn't hesitate to recommend this upgrade from Nelion Audio.


    2 Carver M500t with MKII upgrade, Parasound P5 Halo preamp, and Definitive Technology BP2000 speakers

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    Evan Finch

       2 of 2 members found this review helpful 2 / 2 members

    I worked as an electronics restoration tech for many years. I saved a smoke-damaged M500 from a fire, meticulously cleaning it with pressurized DI water and surfactant. 

    I used the amp for years until one day my wife's friend plugged a 3.5mm adapter from the input directly into her phone, cooking the right rail as the phono jack shorted. I fixed the first stage, but as the current came up it cooked again. 

    Greg fixed my baby, making it better than ever. This amp means more to me than any other physical possession. Just do the MKII service--it's cheaper than buying many consumer receivers, and for it you'll get 30 more years from one of Bob Carver's coolest all-around designs. 

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    John Smallwood

       1 of 1 member found this review helpful 1 / 1 member

    I have two M500t amps, and had both restored by someone I found on eBay.  I had major/minor problems with both, so I sent them to Greg to look at.  Greg opened them and sent me photos of what he found, and it's clear that someone who does not know electronics can be taken advantage of, as I was to some degree. 

    So, bite the bullet and get your amp done right, by Greg, the first time.  You'll save yourself a lot of time and money.  Looking at the attached "before and after" photo, even to my inexperienced eye I can clearly see the difference between the "'eBay build" and Greg's workmanship. 

    The amps sound fantastic, and I look forward to many years of enjoyment with them. 


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