question- to turn off rack gear or use a power strip On/OFF

As it 'appens! My laptop ran out of juice overnight and would not start this morning even with the charger connected. The clover leaf mains conn' had popped out.

Now, of course a battery dies slowly in a lappy but if you just drop the battery out whilst running all that happens on re-connection is it starts in Safe Mode with options. No drama whatsoever.

Dave.
 
Disclaimer -- I turn my stuff off. I'm pulling around 6A with the usual stuff running (not counting lights, computers & video monitors, etc.). That bill would be too damn high.

Same here...I always turn my gear off at the end of the night.
If I left my console, tape decks and racks on all the time...I would be working just to pay the electric bill.


Just the console and 2" deck will pull 6A...add the monitors and a guitar amp and some rack gear...I'm already pulling a good 10A-12A.
On a really "full" day, where I use a good amount of rack gear...I've seen the meter up as high as 16A on my power distro setup.
When I'm just on the computer and only the studio monitors powered up...it's not bad, but I still see no reason to leave them on all night long eating up power.
There's nothing to be gained from leaving them powered up. I've never lost a piece of gear because of power up or power down.
I also run multiple levels of protection, voltage regulation on the whole studio...plus balanced power on most of my analog audio gear, though not any kind of power amps, they run better without it.
 
If you think about it, no equipment manufacturer worth their salt is going to produce gear that cannot be shut down and powered up with impunity many times a day in its lifetime. The kit will also be designed to be proof against power loss, mains borne RF and modest voltage spikes (a good solid 50/60Hz power traff helps a LOT there!) This means not only the circuitry but the mains switch itself should be ok for say 50,000 operations.

Of course, there is now a lot of very cheap gear about. I mention no names but I will quote lord Sugar (HTF?) "There is very little in this world that someone cannot make a little cheaper and a little worse".

There might of course be perfectly well designed equipment that has certain sensitive circuitry that demands special treatment at switch on and shut down but in such a case the mnfctrs SHOULD give very specific instructions.

And, BTW, "stand by" switches on valve guitar amps are an anachronism, they do more harm than good especially if the amp uses a thermionic rectifier, i.e. a valve.

Dave.
 
And, BTW, "stand by" switches on valve guitar amps are an anachronism, they do more harm than good especially if the amp uses a thermionic rectifier, i.e. a valve.

Dave.

As long as you don't flip the Standby on/off too fast in succession, and you pause a bit between Power and Standby....and there should be a fuse there too.

For the studio, they are a necessity. I hate amps without them, because then I have to turn down volume on the guitar and/or amp if I'm going to switch guitars...and that can upset how you have things dialed in...etc.
 
As long as you don't flip the Standby on/off too fast in succession, and you pause a bit between Power and Standby....and there should be a fuse there too.

For the studio, they are a necessity. I hate amps without them, because then I have to turn down volume on the guitar and/or amp if I'm going to switch guitars...and that can upset how you have things dialed in...etc.

I have had this discussion many times before Mr M and you are the FIRST guy to come up with a valid reason for the frigging things. One theory is similar to yours that when amps appeared in big bands the player needed a temporary mute.

Yes, yours is a valid need but there are better ways to do it. Bias the OP valves to cut off (Blackstar) or simply short the speaker feed but I don't know of any mnfctr that does that.

Dave.
 
Bias the OP valves to cut off (Blackstar) or simply short the speaker feed but I don't know of any mnfctr that does that.

Dave.

Not to go off-topic here...but you might find this interesting.

Right now I'm using some high-end amps from Carol Ann Amps, and their more recent build models now all come with an auto-bias system.
This is something no other amp manufacture has ever done, AFIK...it's a completely original design by Alan Phillips.
Basically...you can bias the tubes with a single button press, and it also monitors the electronics and performance, so it acts as a front line protection scheme that prevents any major amp failure. It will power off the amp if any faults are detected...and it will also warn you of a power tube going bad or one that won't bias. There's multi-colored LEDs that signify different states.
He also incorporates into that design an easy way to exchange power tube types...by way of the auto-bias system and a couple of dip switches internally.
I know other amps that allow the use of different power tubes....I owned a TDH Flexi for awhile that could do that, and it also provided a couple of external bias points, but you adjusted those manually with trim pots...but I don't think any other amp manufacture does a microprocessor controlled tube power amp.

You can read about it here:

https://www.carolannamps.com/uploads/2/7/3/6/27361629/carol-ann_autobiasmon_v1.00.pdf

He does a video demo of the system here:

Carol-Ann Amplifiers News

I've got three of his amps now...an early model OD2r that is cathode biased, so no auto-bias system needed...a Texas 50 that has the earlier semi-manual BiasMon system, and most recently a Revo 1 MKII that has the full AutoBiasMon system.

Anyway...this guy builds absolutely phenomenal guitar tube amps. I have one more of his amps in sight...for maybe later this year.
Everything is over-built...superb circuit design and implementation (the guy has an engineering degree...he's not just someone who builds by cloning)...and he's also a player, so he knows how to tune each individual amp build to get the best tones. He doesn't just follow a set blueprint and assembly-line process. Each amp is given a one-off kind of build that he adjusts as needed.
When I got my Revo...I liked the amp, but wanted a couple of tonal tweaks that departed a bit from the original design and to suit my tastes more...so I sent it to him, and he returned it to me with every tweak like I imagined it. He knows WTF he's doing. :cool:
 
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Very interesting Miroslav. I have seen bias servo circuits before (Jones) and have had the odd dabble with ideas on backs of envelops! The problem is twofold for "regular" amps on the market.

1) Complexity. I have tried to come up with a very simple circuit that uses standard OP amps and transistors, once you get into microprocessors things get tricky and expensive and reading the operation of those amps tells me the average Joe guitarist would be baffled and do it wrongly.

2) Reliability. Not so much the CPU system itself, I mean, how often do AI go wrong? No, it is "collateral" damage that can be the problem. If a KT88 with 600V on its anode (plate) goes ape***t and dumps Fknows how many Joules into the cathode circuit (where the sense circuit will be) it is very hard to protect it.

I am also a little bothered by their control of positive grid voltage and hence grid current? Not something you ever want in a hi fi amp for sure but a leeetle bit of G! give a certain tone to an amp? If you had ever heard those old fairground amps that used 807 TX valves in near class B (sod all idle current) they had a certain "bark" that got your attention!

OT? Yes but, what forums is all about no? Got to go sleep but tomm' I shall bang on a bit about the amps I worked on, if I may?

Dave.
 
Oim beck!

Some of you might know of the Blackstar Series One amplifiers and their (unique?) Dynamic Power Control system? Not the place to go into that but a consequence of the control circuitry is that a conventional "bang the ***t of everything off and on" was not possible. The result was a standby system ('cos' peeps want 'em!) which worked by slamming a high bias on the output valve control grids and effectively shutting them down.

This has several knock on possibilities...

Since ONLY the OPVs are "dead" the rest of the amplifier can be used as a pre amp with all the OD, tone stack and MIDI circuits available. Output is FX out, a straight signal that would go to the PI and "emulated" which is suitable for a mixer/recording/PA situation.

Additionally there are sensors on the input and speaker jacks. ONLY if a plug is in BOTH jacks with the OP valves be fired up and so in the absence of a guitar plugged in the amp is silent (but poised!) Also, if a speaker jack is yanked or forgotten, the amp cannot be damaged by accidental drive.

These features were then exported to the HT range of amps (not the HT-5, different time/designer)

All the valve products were designed such that a valve failure, even a catastrophic anode-cathode short of a KT88 running 700V Va did little or no damage to surrounding circuitry*.

Much of my time at B's was spent trying to destroy amps! They were rigged to run at max mains, 253V here and signal was on 5, of 5 mins at 50% rated power. Eventual failure, if it occurred, was generally a valve then a fuse. No other circuitry was ever smoked.

I tell this tale not as "spam" but because the designs have been copied, at least externally and the extra "engineering" the company does is hidden but adds to costs. Do the rip off artists build to the same standards?

*Yes, I did see one amp with damage. IIIRC a resistor in a bias feed was brown as was the 10k grid stopper (S1 200) but they had NOT changed value significantly and there was no damage to the PCB. There was a particularly shit batch of KT88s.

Dave.
 
So you worked at Blackstar?

Yes, for a time when they were just starting up. The HT pedals had just gone onto the market (a heck of a tale in itself!) and the Artisan combo range were in their final stages and were released a few months later.

We worked out of a garage at the bottom of the MD's garden for some months! Such Fun!

Dave.
 
Oh, cool. Sounds like some adventure was had

Yes, nice people, interesting work. I had to stop after The Big C got me but then they asked me back for a tine after I had retired. Then wife's health took a nosedive off a cliff so I had to jack it all in and become a carer.

I know the company has had some stick in some quarters and the amp's tones seems a bit "Marmite" but I found them very ethical and determined to build the most reliable gear they could at fair prices.

Just one product. The Artisan A100 is a conventional 4xEL34 100W amp, all valves (but a bombproof 1000V 15A HT Si rect) and you will look long and hard to find a more reliable amplifier. The Boy Wonders that had them a s loaners tried their best to bust them but short of actual physical damage they rarely succeeded!

Dave.
 
personally all my gear is plugged into a furman power conditioner surge protector that is on 24/7...i don't mind turning individuals off ( you can plug a power strip into a furman channel if you desire i suppose...but the reason i do this is because i live in tornado alley Missouri... the furman has protected me more than once through an unsuspected storm...and even when things are turned off "except for the furman" things can get lightning spiked... so the power conditioner stays on...it has saved my Alesis HD24 hard disc recorder my interfaces my mixing console not to mention my computer and Modem from frying... :thumbs up::listeningmusic::guitar:
 
personally all my gear is plugged into a furman power conditioner surge protector that is on 24/7...i don't mind turning individuals off ( you can plug a power strip into a furman channel if you desire i suppose...but the reason i do this is because i live in tornado alley Missouri... the furman has protected me more than once through an unsuspected storm...and even when things are turned off "except for the furman" things can get lightning spiked... so the power conditioner stays on...it has saved my Alesis HD24 hard disc recorder my interfaces my mixing console not to mention my computer and Modem from frying... :thumbs up::listeningmusic::guitar:

One way to protect studio gear as a whole from lightning strike (to a degree. If the chimney comes through the roof..end of!) is a Big Mother isolating transformer and it MUST be an ISOLATING transformer with a double winding and an inter-winding electrostatic shield.

Such a traff shields in two ways essentially. One is the E shield that stops fast pulses getting from mains side to secondary. The other is, in the event of a massive current pulse the core saturates. This presents a dead short to the breakers which promptly trip. Then, a saturated transformer is no longer "A transformer"! and Jack S gets through.

Note very B. The Iso T MUST power ALL the gear in the room and MUST be installed by a qualified sparks who knows about such matters. I understand in the States such traffs are often a 55-0-55 volt secondary and the "0" taken to ground, i.e. a "balanced" mains supply. The technique is rarely used in 240V EU except for scientific/medical supplies where there is little chance of an uninformed person opening up kit.

At one time 55-0-55 traffs were used on building sites here so the worse case shock hazard was 55V above earth (bad enough if you are standing in water!) I suspect most kit is now 230V but double insulated and fed from RCD supplies?

Dave.
 
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