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    New M125 ownership phase

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    LeGrace

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    New M125 ownership phase

    Post by LeGrace on Sun Dec 04, 2016 9:42 am

    Finally shifting into enjoyment phase of these wonderful amps. So long paranoia phase!! Now I just sit back, relax, and enjoy. And smile a lot. Very Happy I tried just two output tubes for awhile, that was insanity phase! Hang the cost, they just sound so much more dynamic when all four output tubes are installed.

    I've learned a lot from good folks in this forum. You've helped me through my rectifier issues, and guided me through the tube types jungle. My M125's are so stable now! Thanks for sharing your time and knowledge.

    I tend to jump around with my hardware, but my M125's are keepers. I mean they even make CD listening a pleasurable experience, which is saying a lot. I just love the way they make the music come alive, they are like the secret ingredient that makes the sauce special! cheers
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    10-E-C

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    Re: New M125 ownership phase

    Post by 10-E-C on Sun Dec 04, 2016 11:06 am

    LeGrace wrote:Finally shifting into enjoyment phase of these wonderful amps. So long paranoia phase!! Now I just sit back, relax, and enjoy. And smile a lot. Very Happy I tried just two output tubes for awhile, that was insanity phase! Hang the cost, they just sound so much more dynamic when all four output tubes are installed.

    I've learned a lot from good folks in this forum. You've helped me through my rectifier issues, and guided me through the tube types jungle. My M125's are so stable now! Thanks for sharing your time and knowledge.

    I tend to jump around with my hardware, but my M125's are keepers. I mean they even make CD listening a pleasurable experience, which is saying a lot. I just love the way they make the music come alive, they are like the secret ingredient that makes the sauce special! cheers


    Congrats on your M125's, I finished my build on 24 Dec 14 and they have been playing ever since. I've put a lot of hours on them and they preform magnificently. I've ran both 4 and 2 output tubes and settled on 2, my speakers are so efficient I couldn't tell any differents between two or four.

    TM
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    deepee99

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    Re: New M125 ownership phase

    Post by deepee99 on Sun Dec 04, 2016 11:57 am

    10-E-C wrote:
    LeGrace wrote:Finally shifting into enjoyment phase of these wonderful amps. So long paranoia phase!! Now I just sit back, relax, and enjoy. And smile a lot. Very Happy I tried just two output tubes for awhile, that was insanity phase! Hang the cost, they just sound so much more dynamic when all four output tubes are installed.

    I've learned a lot from good folks in this forum. You've helped me through my rectifier issues, and guided me through the tube types jungle. My M125's are so stable now! Thanks for sharing your time and knowledge.

    I tend to jump around with my hardware, but my M125's are keepers. I mean they even make CD listening a pleasurable experience, which is saying a lot. I just love the way they make the music come alive, they are like the secret ingredient that makes the sauce special! cheers


    Congrats on your M125's, I finished my build on 24 Dec 14 and they have been playing ever since. I've put a lot of hours on them and they preform magnificently. I've ran both 4 and 2 output tubes and settled on 2, my speakers are so efficient I couldn't tell any differents between two or four.

    TM

    Welcome to Tommy's Holiday Camp, never mind the weather, the holiday's forever! I was snookered in to some modifications of the M-125s, each of which dropped dead or blew up fuses and tubes. Don't go down that road. The stock M-125s, built well, will indeed just keep sounding better over time. I run two output tubes in summer, all four in the winter. Saves on the gas bill. Smile. My only serious advice is, as Bob L quite clearly says in the destruction manual, is keep an eye on the output tube bias. He recommends monthly, I would recommend a bit more frequently, bearing in mind that input voltages, which vary, will influence your readings. This is especially important right after an output or rectifier tube change. Watch 'em like a hawk for a few days (given line voltage fluctuations) then relax.
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    LeGrace

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    Re: New M125 ownership phase

    Post by LeGrace on Wed Dec 07, 2016 8:06 pm

    I used to hyperventilate on turning them on. Now I don't even flinch, talk about nice. In UL mode I don't notice much of a difference between 2 and 4 output tubes, but in preferred triode mode 4 tubes does seem to offer more punch.
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    Tube Nube

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    Re: New M125 ownership phase

    Post by Tube Nube on Wed Dec 07, 2016 11:45 pm

    Congratulations in emerging from the stage of paranoid/schizoid confusion and doubt, and arriving in the situation that brings clarity, organization and satisfaction.

    Dogstar

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    Re: New M125 ownership phase

    Post by Dogstar on Wed Dec 07, 2016 11:55 pm

    As much as I really enjoy my ST-120 i am a bit jealous of you M125 owners. Not to hijack the thread but would two ST-120's that are hooked up bi-amp ready speakers be close to equivalent performance wise to a pair of M125's?
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    Tube Nube

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    Re: New M125 ownership phase

    Post by Tube Nube on Thu Dec 08, 2016 2:15 am

    Dog,

    I think the merits of the tyle of bi ampi g you propose really come into their own when you use a hifi quality electronic, or "activ" cross over between pre and power amps. Some companies like Naim produce their own cross overs for this purpose that match their own speakers so you can run multi amps. Ghe external active cross over jere would be replacing the internal crossover built into the speaker. I don't know what's on the market that's not speaker-specific (like the naim or linn systems), but I'd be curious.
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    Bob Latino
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    Re: New M125 ownership phase

    Post by Bob Latino on Thu Dec 08, 2016 8:30 am

    Dogstar wrote:As much as I really enjoy my ST-120 i am a bit jealous of you M125 owners. Not to hijack the thread but would two ST-120's that are hooked up bi-amp ready speakers be close to equivalent performance wise to a pair of M125's?

    I have done the single M-125 per channel vs. the single ST-120 (biamped) per channel and can report that the sound is pretty much the same. The only caveat is that yes - your speakers are biamp ready AND that when the woofer or tweeter sections are split up, neither ALONE presents an odd impedence to the output transformer of the ST-120. Every speaker is different .. You might try your ONE ST-120 on ONE of your speakers in a biamped configuration just to see if it works OK ?

    Bob
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    LeGrace

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    Re: New M125 ownership phase

    Post by LeGrace on Thu Dec 08, 2016 8:40 am

    Dogstar wrote:As much as I really enjoy my ST-120 i am a bit jealous of you M125 owners. Not to hijack the thread but would two ST-120's that are hooked up bi-amp ready speakers be close to equivalent performance wise to a pair of M125's?

    Unfortunately not, because of the quirks of biamping. Would hardly be any different versus a single ST120.

    Power wise it may look the same on paper, but consider what is happening to that power. You physically separate the bass unit(s) from the mid and high freq drivers. Then you allocate each 60 watts. 120 watts total, so same as M125, right? Well no. In the biamp configuration the bass driver is limited to 60 watts. In a non biamp configuration with M125's it can pull a lot more then 60w from the 125 watts that's on tap. The guy who needs it, the bass driver, really isn't seeing hardly anymore then he was before with a single ST120. So the extra 60 watts goes largely unused since the other drivers don't demand a lot. This unequal power demand is what defeats a lot of biamp attempts.

    Now if you bridge the ST-120's to mono (assuming one can do that, I see a stereo/mono switch?) and use one per each channel, now its basically equivalent. And will sound much better then the same two units in a biamp configuration because the power can go to where its most needed.

    The very unequal power needs of the various drives is why biamp folks often like to combine a low power tube amp with a beefy SS amp for the bass. But then you need an external crossover for it to work properly. When identical amps are used you can get away without an external crossover, but is rarely an efficient use of amps for the reasons cited above.
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    deepee99

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    Re: New M125 ownership phase

    Post by deepee99 on Thu Dec 08, 2016 8:46 am

    You might try bi-wiring as opposed to bi-amping if your speakers are set up for it. Made a huge improvement in Vandersteens. Tylers don't seem to need it so it's a hit or miss kind of thing.
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    Peter W.

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    Re: New M125 ownership phase

    Post by Peter W. on Thu Dec 08, 2016 9:18 am

    deepee99 wrote:You might try bi-wiring as opposed to bi-amping if your speakers are set up for it. Made a huge improvement in Vandersteens. Tylers don't seem to need it so it's a hit or miss kind of thing.

    What gauge wiring are you using? And at what distance?
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    Peter W.

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    Re: New M125 ownership phase

    Post by Peter W. on Thu Dec 08, 2016 9:24 am

    LeGrace wrote:
    Dogstar wrote:As much as I really enjoy my ST-120 i am a bit jealous of you M125 owners. Not to hijack the thread but would two ST-120's that are hooked up bi-amp ready speakers be close to equivalent performance wise to a pair of M125's?

    Unfortunately not, because of the quirks of biamping. Would hardly be any different versus a single ST120.

    Power wise it may look the same on paper, but consider what is happening to that power. You physically separate the bass unit(s) from the mid and high freq drivers. Then you allocate each 60 watts. 120 watts total, so same as M125, right? Well no. In the biamp configuration the bass driver is limited to 60 watts. In a non biamp configuration with M125's it can pull a lot more then 60w from the 125 watts that's on tap. The guy who needs it, the bass driver, really isn't seeing hardly anymore then he was before with a single ST120. So the extra 60 watts goes largely unused since the other drivers don't demand a lot. This unequal power demand is what defeats a lot of biamp attempts.

    Now if you bridge the ST-120's to mono (assuming one can do that, I see a stereo/mono switch?) and use one per each channel, now its basically equivalent. And will sound much better then the same two units in a biamp configuration because the power can go to where its most needed.

    The very unequal power needs of the various drives is why biamp folks often like to combine a low power tube amp with a beefy SS amp for the bass. But then you need an external crossover for it to work properly. When identical amps are used you can get away without an external crossover, but is rarely an efficient use of amps for the reasons cited above.  

    This makes a great deal of sense - and why I have always been an advocate of "more power" through the on-board crossover over bi-amp configurations using identical amplifiers. Some few speakers split the load reasonably evenly - again, on paper - but then the signal will very much determine where the power actually goes. And if one has pretty much exclusively as I do, power-pig speakers (the most efficient is 86dB/meter/1 watt), More Power is the most effective option.
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    deepee99

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    Re: New M125 ownership phase

    Post by deepee99 on Thu Dec 08, 2016 9:27 am

    Peter W. wrote:
    deepee99 wrote:You might try bi-wiring as opposed to bi-amping if your speakers are set up for it. Made a huge improvement in Vandersteens. Tylers don't seem to need it so it's a hit or miss kind of thing.

    What gauge wiring are you using? And at what distance?

    Hi, Peter, I'm running 10-gauge silver, 10 feet per side. A bit of overkill but I like the sound.
    I could get by with 8 feet each direction but the extra couple of feet leaves a bit of manoeuvring room.
    When I had the Vandersteens, I ran two lengths of copper, same gauge and distance for bi-wiring.
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    Peter W.

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    Re: New M125 ownership phase

    Post by Peter W. on Thu Dec 08, 2016 10:01 am

    Well, 10-gauge silver is impressive, and probably good for about any developed length practically needed. Silver is the closest thing to a super-conductor available at room temperature. Solid or stranded? I expect stranded. But I have to ask.

    Was the copper also 10-gauge, or 'both the same' of some lesser gauge? Parsing it on its face, 10-gauge x 2 at 10 feet.
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    deepee99

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    Re: New M125 ownership phase

    Post by deepee99 on Thu Dec 08, 2016 10:23 am

    Peter,
    The silver cables I have are solid core. Makes them a bit tough to route without disturbing the connector ends, but if you do a little pre-bending ahead of the contact all goes well.
    Few people seem to know this, but silver is actually a better conductor than gold, all other things being equal. And tarnishing does not much reduce its conductivity as tarnish is a result of contact with sulphur, not oxygen -- unlike Cu.
    Yes, when I was bi-wiring with Cu, I ran parallel lines of 10-gauge to the Vandies. As I mentioned, the Vandersteens liked that configuration but it seems to have no influence on the Tylers. Mebbe it's an efficiency thing. The Vandies are about 88 dB and the Tylers are 91 dB. I thought bi-wiring was a bunch of hokum until I tried it on the Vandies.
    A single length of 10-ga silver is working just fine for me. I don't plan to change it.


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    Peter W.

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    Re: New M125 ownership phase

    Post by Peter W. on Thu Dec 08, 2016 10:52 am

    Gold has one (1) actual virtue in the electronics hobby. It tends to corrode less than other metals.
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    corndog71

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    Re: New M125 ownership phase

    Post by corndog71 on Thu Dec 08, 2016 11:23 am

    Seems like your best bet is to save your money for the M125s. Wink I kind of want a pair too but I have bills to pay.
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    deepee99

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    Re: New M125 ownership phase

    Post by deepee99 on Fri Dec 09, 2016 5:06 am

    I've never A:B'd the ST-120 and the M-125s as I've only had the latter. Would be an interesting trial.
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    LeGrace

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    Re: New M125 ownership phase

    Post by LeGrace on Fri Dec 09, 2016 7:46 am

    deepee99 wrote:I've never A:B'd the ST-120 and the M-125s as I've only had the latter. Would be an interesting trial.

    I imagine a lot will depend on speakers employed, and to some degree adjacent factors like room size and listening levels.  Curious thing I'm finding about owning higher quality speakers, I'm playing my new Tannoys at louder levels then previously. As my poor wife can attest! (becoming a bit of an issue actually, I try to align my listening now with her shopping times  Laughing )  They are just so clear sounding! And probably why in triode mode I'm preferring 4 tubes, since my audio room is somewhat large as well. Anyone else have similar experience?

    Dogstar

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    Re: New M125 ownership phase

    Post by Dogstar on Fri Dec 09, 2016 8:49 am

    Bob Latino wrote:
    Dogstar wrote:As much as I really enjoy my ST-120 i am a bit jealous of you M125 owners. Not to hijack the thread but would two ST-120's that are hooked up to bi-amp ready speakers be close to equivalent performance wise to a pair of M125's?

    I have done the single M-125 per channel vs. the single ST-120 (biamped) per channel and can report that the sound is pretty much the same. The only caveat is that yes - your speakers are biamp ready AND that when the woofer or tweeter sections are split up, neither ALONE presents an odd impedence to the output transformer of the ST-120. Every speaker is different .. You might try your ONE ST-120 on ONE of your speakers in a biamped configuration just to see if it works OK ?

    Bob

    Configuring the setup so one ST-120 amp per speaker is the way I was thinking when I asked the question. I think that eliminates the need for an active crossover. Is that correct?
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    Bob Latino
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    Re: New M125 ownership phase

    Post by Bob Latino on Fri Dec 09, 2016 9:16 am

    You won't need an active crossover if you use TWO VTA ST-120's to drive your speakers. The ST-120's are very tolerant of odd loads and will drive virtually all speakers in which the speaker has been divided into woofer and tweeter sections. Below is a photo of my downstairs system taken in 2010. At that time I was using two ST-120's to drive a pair of Magnepan 3.6R planar magnetic speakers. I now have a pair of M-125's driving these speakers. One of the ST-120's was sold and the other is upstairs driving my Tyler Acoustics speakers. The sound of the system was basically the same with equal power, soundstaging, headroom etc. whether the two ST-120's or the two M-125's were being used on this system ..

    Bob



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