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    ST-120 Power Switch Move

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    jimmeq

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    Post by jimmeq on Thu Feb 14, 2019 2:13 pm

    I'm trying something different; asking first. So, rather than making a change and seeking help on how to get out of trouble, I am seeking advice beforehand.

    My ST-120 is on the bottom shelf. There are three fans keeping the heat at bay so that's not an issue. What is an issue is having to get down on my knees and reaching back to power on and off. This wouldn't be so bad if I were not entering my sixth decade but no matter what it's in a hard to reach location.

    So, I want to put the power switch up front where the attenuator would go. Is there any reason not to do this? If it is OK, what should I be aware of?

    peterh
    peterh

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    Post by peterh on Thu Feb 14, 2019 2:27 pm

    jimmeq wrote:I'm trying something different; asking first. So, rather than making a change and seeking help on how to get out of trouble, I am seeking advice beforehand.

    My ST-120 is on the bottom shelf. There are three fans keeping the heat at bay so that's not an issue. What is an issue is having to get down on my knees and reaching back to power on and off. This wouldn't be so bad if I were not entering my sixth decade but no matter what it's in a hard to reach location.

    So, I want to put the power switch up front where the attenuator would go. Is there any reason not to do this? If it is OK, what should I be aware of?

    Running main AC under the preamp and close to the input might generate hum.
    Have you considered other options first ?
    (1) running the amp from a "power strip" that has a power switch ?
    (2) or even a power strip with a sensor relay where you preamp is connected to
    the controlling outlet ( when preamp is turned on all outer outlets will be live)
    (3) installing a relay ( preferably SSR ) inside the vta-120 controlled by a small DC
    taken from something else ( preamp etc)

    1 and 2 will not need any changes of the vta-120
    3 will install a component and a signal inlet in the vta-120
    Peter W.
    Peter W.

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    Post by Peter W. on Thu Feb 14, 2019 2:39 pm

    jimmeq wrote:I'm trying something different; asking first. So, rather than making a change and seeking help on how to get out of trouble, I am seeking advice beforehand.

    My ST-120 is on the bottom shelf. There are three fans keeping the heat at bay so that's not an issue. What is an issue is having to get down on my knees and reaching back to power on and off. This wouldn't be so bad if I were not entering my sixth decade but no matter what it's in a hard to reach location.

    So, I want to put the power switch up front where the attenuator would go. Is there any reason not to do this? If it is OK, what should I be aware of?


    KISS...

    https://www.amazon.com/FosPower-Wireless-Control-Resistant-Electrical/dp/B0798W2TZ1/ref=asc_df_B0798W2TZ1/?tag=hyprod-20&linkCode=df0&hvadid=241986552631&hvpos=1o1&hvnetw=g&hvrand=931701768402974150&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9060374&hvtargid=pla-442272177981&psc=1

    They come as 1, 2 and 3 -outlet devices, typically rated around 15 amps, typically less than $20.
    peterh
    peterh

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    Post by peterh on Thu Feb 14, 2019 4:06 pm

    Peter W. wrote:
    jimmeq wrote:I'm trying something different; asking first. So, rather than making a change and seeking help on how to get out of trouble, I am seeking advice beforehand.

    My ST-120 is on the bottom shelf. There are three fans keeping the heat at bay so that's not an issue. What is an issue is having to get down on my knees and reaching back to power on and off. This wouldn't be so bad if I were not entering my sixth decade but no matter what it's in a hard to reach location.

    So, I want to put the power switch up front where the attenuator would go. Is there any reason not to do this? If it is OK, what should I be aware of?


    KISS...

    https://www.amazon.com/FosPower-Wireless-Control-Resistant-Electrical/dp/B0798W2TZ1/ref=asc_df_B0798W2TZ1/?tag=hyprod-20&linkCode=df0&hvadid=241986552631&hvpos=1o1&hvnetw=g&hvrand=931701768402974150&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9060374&hvtargid=pla-442272177981&psc=1    

    They come as 1, 2 and 3 -outlet devices, typically rated around 15 amps, typically less than $20.

    Perfect as number 4 on the list. Could be used to switch a power strip for all equipment.
    Also means "no change in vta-120"
    GreggW
    GreggW

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    Post by GreggW on Thu Feb 14, 2019 8:30 pm

    I moved the power switch to the front of my 120, running the wires along the bottom edge of the chassis as far away from other wires as possible. My amp sits high on a shelf, so the switch was a little hard to reach. No hum...
    aguaazul
    aguaazul

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    Post by aguaazul on Fri Feb 15, 2019 11:33 am

    Peter W. wrote:
    jimmeq wrote:I'm trying something different; asking first. So, rather than making a change and seeking help on how to get out of trouble, I am seeking advice beforehand.

    My ST-120 is on the bottom shelf. There are three fans keeping the heat at bay so that's not an issue. What is an issue is having to get down on my knees and reaching back to power on and off. This wouldn't be so bad if I were not entering my sixth decade but no matter what it's in a hard to reach location.

    So, I want to put the power switch up front where the attenuator would go. Is there any reason not to do this? If it is OK, what should I be aware of?


    KISS...

    https://www.amazon.com/FosPower-Wireless-Control-Resistant-Electrical/dp/B0798W2TZ1/ref=asc_df_B0798W2TZ1/?tag=hyprod-20&linkCode=df0&hvadid=241986552631&hvpos=1o1&hvnetw=g&hvrand=931701768402974150&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9060374&hvtargid=pla-442272177981&psc=1    

    They come as 1, 2 and 3 -outlet devices, typically rated around 15 amps, typically less than $20.

    These look pretty cool. Has anyone checked these for added line noise? In the DIY power supply world, some are pretty particular as to what LEDs are used due to noise, etc.

    I'll order a 2 pack & run the line test with my O-Scope. If they end up noisy, they can still be used elsewhere.

    Bluewater
    Peter W.
    Peter W.

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    Post by Peter W. on Fri Feb 15, 2019 12:07 pm

    I believe these devices use a mechanical relay - for that kind of rating (15A), a solid-state device would be a bit costly for a $20 unit to a ratio of about 8:1.  See the mechanical relay as a sophisticated, but conventional switch and this should reassure you a little bit.

    I should add that I put one of these on our gas-log, and it does use a mechanical relay.
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    jimmeq

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    Post by jimmeq on Fri Feb 15, 2019 2:13 pm

    Thanks for the recommendation and insight. Asking first worked out great! I actually have one. https://www.amazon.com/gp/product/B072F9DGRL/ref=ppx_yo_dt_b_asin_title_o01__o00_s00?ie=UTF8&psc=1 that I got for the fans but since I kept forgetting to turn them off I plugged them into my preamp. No noise so it's working out. I thought about trying the remote switch but thought it might introduce noise into the AC line. Not sure why I just didn't try it.

    Trying this is free so I'll try it out this weekend. I'd also like to see how they scope out...
    Peter W.
    Peter W.

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    Post by Peter W. on Fri Feb 15, 2019 2:18 pm

    I suspect that your ears will take precedence over your eyes in this case, or should. But give it a least 72 hours of listening before pronouncing judgement - and also, please let us know!
    bbqjoe
    bbqjoe

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    Post by bbqjoe on Sun Feb 17, 2019 10:48 am

    I have also given consideration to moving the power switch to the front.
    I dislike reaching behind anything electrical, and especially reaching over hot tubes.

    Wouldn't simply twisting the wires to the switch and routing them along the inside edge of the chassis suffice?

    Bob Latino
    Bob Latino
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    Post by Bob Latino on Sun Feb 17, 2019 11:56 am

    bbqjoe wrote:I have also given consideration to moving the power switch to the front.
    I dislike reaching behind anything electrical, and especially reaching over hot tubes.

    Wouldn't simply twisting the wires to the switch and routing them along the inside edge of the chassis suffice?


    If you absolutely need a power switch on the front, then you could plug the amp into a "power strip". You leave the switch on the amp ON and then keep the power strip near the front of your music system. Every time you turn the power strip ON, the amp comes on.

    Bob
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    jimmeq

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    Post by jimmeq on Mon Feb 18, 2019 9:00 am

    This worked out great! I plugged the ST-120 into a Fosman AC Remote and it is working fine. I do not hear any added noise at all. I have to say I feel a bit odd turning on the tube amp with a remote but in a short time I'm sure I'll get over it.

    Thanks to everyone for the ideas!
    bbqjoe
    bbqjoe

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    Post by bbqjoe on Mon Feb 18, 2019 9:24 am

    Bob Latino wrote:
    bbqjoe wrote:I have also given consideration to moving the power switch to the front.
    I dislike reaching behind anything electrical, and especially reaching over hot tubes.

    Wouldn't simply twisting the wires to the switch and routing them along the inside edge of the chassis suffice?


    If you absolutely need a power switch on the front, then you could plug the amp into a "power strip". You leave the switch on the amp ON and then keep the power strip near the front of your music system. Every time you turn the power strip ON, the amp comes on.

    Bob

    Yeah I get it.
    Maybe I'll use a "Clapper" (clap on, clap off...The clapper!®️) Very Happy

    But seriously, I think I'd prefer a toggle on the front.
    Peter W.
    Peter W.

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    Post by Peter W. on Mon Feb 18, 2019 9:37 am

    bbqjoe wrote:

    Yeah I get it.
    Maybe I'll use a "Clapper" (clap on, clap off...The clapper!®️) Very Happy

    But seriously, I think I'd prefer a toggle on the front.

    This reminds me of a true Story:

    For my sins, I make my living as a Property/Facilities Manager, and have done so for the last nearly 40 years, across pretty much aspects of the trade from single-site residential to luxury high-rise to gated communities, offices, retail, educational, medical and industrial - presently medical (acute-care hospital). I have had more than my fair share of difficult clients, from Great Aunt Esmeralda who was perpetually too hot or too cold, to prima-dona professors and researchers who want what they want, only right now.

    The single most common complaint that I have gotten over the years, and that must always be taken seriously are the too-hot-too-cold calls:
    a) At least 20% of them are valid on their face.
    b) At lease another 20% are valid due to special circumstances.
    c) It is that annoying 60% where the system(s) are functioning properly, the temperature (and humidity) set-points are correct and being met, but the end-user is still unhappy.

    It is called the "Dummy" thermostat. It must have (at least one) light(s).
    And it must make a noise every so often. When I was overseas, I had a supply of Honeywell stats had a little ticking clock on board with a small LED. I could fix it so that the LED came on about every hour for about 20 minutes. The residents were, typically, thrilled.

    If you want a toggle-switch on the front of your amp, put a toggle switch on the front of your amp. But to save it, and eliminate any potential modification problems, don't connect it to anything.


    Last edited by Peter W. on Mon Feb 18, 2019 10:26 am; edited 1 time in total
    bbqjoe
    bbqjoe

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    Post by bbqjoe on Mon Feb 18, 2019 9:45 am

    Peter W. wrote:
    If you want a toggle-switch on the front of your amp, put a toggle switch on the front of your amp. But to save it, and eliminate any potential modification problems, don't connect it to anything.

    Brilliant!!!!
    OK! Very Happy
    sKiZo
    sKiZo

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    Post by sKiZo on Mon Feb 18, 2019 2:18 pm

    One word of advice for anyone wanting to do this - make sure your remote power (whatever option you use) can handle the full amp rating of the gear. With a power bar, the temptation will be there to add other gear to fit all those empty sockets, but make sure you do the math.

    PS ... I moved my power switch up front on my custom build. Same thing, only different. The twisted wires run directly under the VTA board and have not given me any additional noise or problems. Only problem was with an extra power supply I tried using to light the switch (it has an annular neon ring when power is on) - I did get some noise from that so that got pulled. No big loss.

    ST-120 Power Switch Move Bias-meters-ma
    bbqjoe
    bbqjoe

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    Post by bbqjoe on Mon Feb 18, 2019 2:25 pm

    sKiZo wrote:
    PS ... I moved my power switch up front on my custom build. Same thing, only different. The twisted wires run directly under the VTA board and have not given me any additional noise or problems.

    And this is why I don't understand what the fuss is all about. ST-120 Power Switch Move WvNtDnl
    Peter W.
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    Post by Peter W. on Mon Feb 18, 2019 2:52 pm

    bbqjoe wrote:

    And this is why I don't understand what the fuss is all about. ST-120 Power Switch Move WvNtDnl

    There is an old expression: Your Mileage May Vary.

    I once got into a discussion with an individual who made a constant habit of taking the contrarian position - on the basis that he was not a going to be a victim of Group Think. This discussion was on vehicular battery charging systems, and how to keep a battery charged on a stored vehicle when a float charger was not available. Other condition: It it is winter in a cold climate.

    Consensus was: 15  - 20 minutes of run time, about every week to 10 days based on heating the engine through to prevent condensate in the oil and scored cylinder walls. All agreed that this would be vast overkill as to keeping the battery charged, but necessary for the longevity of the engine.

    Our contrarian calculated on the charging capacity of the alternator at 1,000 rpm, battery size and age, and came up with 34 seconds at 1,000 rpm, stating that the water issue was 'debatable', especially over the expected life of the test (about 45 days). Cutting to the chase:

    Fuss:
    a) Generally we  should be resistant to changing a successful design for whimsical purposes, most especially if those/that purpose/s may be accommodated safely and effectively without change.
    b) Due to any number of unknowns, our particular circumstance could be the one that suffers from the change.
    c) Due to any number of unknowns, our particular circumstance could be the one that is greatly enhanced by the change.

    Per Larry Niven (SF Writer:
    When in doubt, do it by The Book - a) above.
    Those who deviate from The Book and fail are court-marshaled - b) above.
    Those who deviate from The Book and are successful - they get into The Book - c) above.

    So, if we want to make changes to established designs - go for it. But be prepared for b) or c). And common sense (which isn't) suggests that if that risk may be avoided without penalty - then, perhaps, avoid it.
    deepee99
    deepee99

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    Post by deepee99 on Sat Mar 02, 2019 4:05 pm

    Peter W. wrote:
    bbqjoe wrote:

    And this is why I don't understand what the fuss is all about. ST-120 Power Switch Move WvNtDnl

    There is an old expression: Your Mileage May Vary.

    I once got into a discussion with an individual who made a constant habit of taking the contrarian position - on the basis that he was not a going to be a victim of Group Think. This discussion was on vehicular battery charging systems, and how to keep a battery charged on a stored vehicle when a float charger was not available. Other condition: It it is winter in a cold climate.

    Consensus was: 15  - 20 minutes of run time, about every week to 10 days based on heating the engine through to prevent condensate in the oil and scored cylinder walls. All agreed that this would be vast overkill as to keeping the battery charged, but necessary for the longevity of the engine.

    Our contrarian calculated on the charging capacity of the alternator at 1,000 rpm, battery size and age, and came up with 34 seconds at 1,000 rpm, stating that the water issue was 'debatable', especially over the expected life of the test (about 45 days). Cutting to the chase:

    Fuss:
    a) Generally we  should be resistant to changing a successful design for whimsical purposes, most especially if those/that purpose/s may be accommodated safely and effectively without change.
    b) Due to any number of unknowns, our particular circumstance could be the one that suffers from the change.
    c) Due to any number of unknowns, our particular circumstance could be the one that is greatly enhanced by the change.

    Per Larry Niven (SF Writer:
    When in doubt, do it by The Book - a) above.
    Those who deviate from The Book and fail are court-marshaled - b) above.
    Those who deviate from The Book and are successful - they get into The Book - c) above.

    So, if we want to make changes to established designs - go for it. But be prepared for b) or c). And common sense (which isn't) suggests that if that risk may be avoided without penalty - then, perhaps, avoid it.

    Bloody brilliant!

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