The Dynaco Tube Audio Forum

Would you like to react to this message? Create an account in a few clicks or log in to continue.
The Dynaco Tube Audio Forum

Dedicated to the restoration and preservation of all original Dynaco tube audio equipment - Customer support for Tubes4hifi VTA tube amp and preamp kits and all Dynakitparts.com products


5 posters

    New guy : new amps

    SixOhms
    SixOhms


    Posts : 9
    Join date : 2023-04-20
    Location : Belgium

    New guy : new amps Empty New guy : new amps

    Post by SixOhms Thu Apr 20, 2023 8:16 am

    Hello everyone,

    I'm in western Europe, after many years of searching for a valve power amplifier to pair with my Velleman K8020 pre I built decades ago I have finally happened upon a well cared for pair of M125's. I gave the seller no opportunity to rethink his selling decision and collected them yesterday evening.

    I have a long history in audio and am a vinyl enthusiast, but I do play digital for the convenience. My current daily driver is an Accuphase E-480 which I have no intention of separating myself from.

    As the M125's have a funky IEC connector and did not come with power cables I'll have to wait a few days for the parts to come in. I will undoubtedly make some updates over time, but first I have to get to now them a bit.

    But for now I have 2 questions :

    1. The driver board is exposed. Is there a particular reason for this ? And
    2. Was or is there a 'cage' available to protect the valves ?

    It currently has 2 matched quad KT88's from TAD on board that allegedly have 400 hours on them. I read the recommended ones are 6550, but I currently don't have the stomach for Russian products. We'll see in the future.

    It also uses a valve rectifier, which I may try to swap with a solid state one for experimentation purposes.

    I did have a Chinese integrated KT88 in the past, so I at least have an inkling of what I'm getting in to.

    Looking forward !

    Pete
    Bob Latino
    Bob Latino
    Admin


    Posts : 3262
    Join date : 2008-11-26
    Location : Massachusetts

    New guy : new amps Empty Re: New guy : new amps

    Post by Bob Latino Thu Apr 20, 2023 9:27 am

    SixOhms wrote:Hello everyone,

    I'm in western Europe, after many years of searching for a valve power amplifier to pair with my Velleman K8020 pre I built decades ago I have finally happened upon a well cared for  pair of M125's. I gave the seller no opportunity to rethink his selling decision and collected them yesterday evening.

    I have a long history in audio and am a vinyl enthusiast, but I do play digital for the convenience. My current daily driver is an Accuphase E-480 which I have no intention of separating myself from.

    As the M125's have a funky IEC connector and did not come with power cables I'll have to wait a few days for the parts to come in. I will undoubtedly make some updates over time, but first I have to get to now them a bit.

    But for now I have 2 questions :

    1. The driver board is exposed. Is there a particular reason for this ? And
    2. Was or is there a 'cage' available to protect the valves ?

    It currently has 2 matched quad KT88's  from TAD on board that allegedly have 400 hours on them. I read the recommended ones are 6550, but I currently don't have the stomach for Russian products. We'll see in the future.

    It also uses a valve rectifier, which I may try to swap with a solid state one for experimentation purposes.

    I did have a Chinese integrated KT88 in the past, so I at least have an inkling of what I'm getting in to.

    Looking forward !

    Pete

    Pete,

    1. The "funky" IEC connector is an audio grade IEC connector and all M-125's come with audio grade power cords. That IEC connector on the amp has a little "bump" inside so that you cannot use a lower grade "computer" power cords. At the link below is a proper power cord for a VTA M-125.

    VTA M-125 power cord for sale

    2. For a VTA M-125 (or a VTA ST-70 or ST-120 amp) driver board cover, get in touch with Rick Green in Stuart, FL. You can Email him at > yanard3(at)gmail(dot)com

    3. A Hammond 1451-29 chassis cover will fit the M-125 chassis BUT the screw holes in this chassis don't line up with the amp chassis. You could just let "gravity" hold it on.

    4. You can use a solid state rectifier in the VTA M-125's. Rick Green, mentioned in #2 above, sells a nice solid state rectifier kit for the M-125's that also works with the VTA ST-70 and the VTA ST-120.

    Bob



    Last edited by Bob Latino on Sat Apr 22, 2023 1:31 pm; edited 1 time in total

    SixOhms likes this post

    SixOhms
    SixOhms


    Posts : 9
    Join date : 2023-04-20
    Location : Belgium

    New guy : new amps Empty Re: New guy : new amps

    Post by SixOhms Thu Apr 20, 2023 9:40 am

    Thanks very much for the info, Mr. Latino. I'm very happy to see you haven't packed it in altogether.  Very Happy

    The plugs are already on order and should arrive in a few days.

    I'll look for the Hammond cover. Unfortunately, importing from the US to Europe has become prohibitively expensive over the last few years, because of bad exchange rates, shortages, and US presidents being unpopular with the EU thieving brigade. I will be shooting Mr. Green an email though.

    Thanks !

    Pete
    peterh
    peterh


    Posts : 1832
    Join date : 2012-12-25
    Location : gothenburg, sweden

    New guy : new amps Empty Re: New guy : new amps

    Post by peterh Fri Apr 21, 2023 1:06 am

    KT88 could be used whereever 6550 is used.
    Seamus
    Seamus


    Posts : 76
    Join date : 2020-03-17

    New guy : new amps Empty Re: New guy : new amps

    Post by Seamus Sat Apr 22, 2023 10:39 am


    It's easy to make a suitable cover from perforated sheet metal.
    This fellow did and has a diagram of how to do it.
    It looks like the cover fits in the gap between the base and bottom.

    New guy : new amps Covers

    New guy : new amps M-125Cover
    SixOhms
    SixOhms


    Posts : 9
    Join date : 2023-04-20
    Location : Belgium

    New guy : new amps Empty Re: New guy : new amps

    Post by SixOhms Sat Apr 22, 2023 12:53 pm

    Seamus wrote:
    It's easy to make a suitable cover from perforated sheet metal.
    This fellow did and has a diagram of how to do it.
    It looks like the cover fits in the gap between the base and bottom.

    That looks very errr...industrial. And there are some high-tech transformer vibration dampers involved too, I see.

    Reminds me I have to finish my power supply cables.

    Thanks for posting !
    avatar
    stewdan


    Posts : 231
    Join date : 2010-03-07
    Age : 85
    Location : Houston Texas

    New guy : new amps Empty New Guy

    Post by stewdan Sat Apr 22, 2023 1:27 pm

    Bob --- could you check the Hammond Number?   I could not find a Hammond 1459-29 chassis cover on their Website.

    I did find a 1451-29 Perforated Chassis Cover ( 10W x 12D x 5+H ), but the configuration is wrong.

    The un-perforated sides of the 1451-29 with the screw holes are shorter than screw hole sides of the M125, which means that the Hammond screw hole sides would line up with the Front and Back of the M125 ( and they have Power/Bias-Socket --- RCA-Input/Speaker-Connections ), assuming that their measurements are correct.  I don't know about the height, since the M125s are 7.1 high with a 2-inch chassis.

    Can you clarify?

    Thanks!
    Bob Latino
    Bob Latino
    Admin


    Posts : 3262
    Join date : 2008-11-26
    Location : Massachusetts

    New guy : new amps Empty Re: New guy : new amps

    Post by Bob Latino Sat Apr 22, 2023 1:43 pm

    stewdan wrote:Bob --- could you check the Hammond Number?   I could not find a Hammond 1459-29 chassis cover on their Website.

    I did find a 1451-29 Perforated Chassis Cover ( 10W x 12D x 5+H ), but the configuration is wrong.

    The un-perforated sides of the 1451-29 with the screw holes are shorter than screw hole sides of the M125, which means that the Hammond screw hole sides would line up with the Front and Back of the M125 ( and they have Power/Bias-Socket --- RCA-Input/Speaker-Connections ), assuming that their measurements are correct.  I don't know about the height, since the M125s are 7.1 high with a 2-inch chassis.

    Can you clarify?

    Thanks!

    You are correct ... That was my error which I corrected in my post above. The correct stock number is 1451-29. Yes - the screw holes don't line up. I did have one customer use a pair of these with the M-125's with the stainless steel chassis. I know he just let it sit on the top of the chassis. I believe that he also had to make some modifications to this Hammond chassis cover so it would sit properly on the two amps. As I recall, he had either curious young children in the house or curious pets that were attracted to the glowing tubes and he didn't want them to unknowingly touch the hot tubes.

    Bob

    Sponsored content


    New guy : new amps Empty Re: New guy : new amps

    Post by Sponsored content


      Current date/time is Fri Apr 19, 2024 9:33 am