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Class D and tripping circuit breakers

Count Arthur

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I'm not sure that they do-is that what an above member called a "snubber"?
No, a snubber a small circuit typically used to prevent arcing in switches and relays: https://en.wikipedia.org/wiki/Snubber

For large transformers, a soft start circuit is designed to limit the the current when first powered on and slowly allow it to come up to full power.
 

Indy

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If you don' care about your electrical bill keep them. Class D amps have come a long way in recent years. I would like to see a USA company that makes a class D for subwoofer duty. The popular go to is a Lab Gruppen clone from china with unpredictable reliability.
 
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Charles_b

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I have Ice Power edge 1200as2 +300a2 (4 channels total) on an 10A plug with it's own 16A circuit breaker on the house board.
Never had a problem even if theoretically they go up to 3000 watts.
Go for D.
Thank you, that's sound advice!
 

Zoomer

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If you don' care about your electrical bill keep them.
Global Warming Poster Clip Art Illustrations, Royalty-Free Vector ...
 

wwenze

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The problem is less of how they draw current during load or idle (where class D and class A will have differences) but rather how they draw current upon power on. Many high-powered ATX PSUs come with NTC thermistor for protection against large inrush currents.

A large capacitance for smoothing 60Hz without inrush current limiting will trip the breaker.

That being said I doubt you are here for the official and professional advices but more for less-accurate hearsay that may actually be more truthful but also less verifiable, so allow me to continue...

The good part about class D is they have a *higher* chance of using SMPS. (Not guaranteed, I know UCD builds using big transformers.) Anyway you can know that just by looking at the insides before buying.

Now, the thing with SMPS is that, they need certification before they can be used and sold, because of FCC regulations. They are also generally way harder to design compared to "linear" or 60Hz power supplies. Like, I once saw in my previous employment my senior replacing a whole batch of SMPS with better output capacitors because the company was too cost-saving the first time. Else the LED lamp will flicker.

Point is, SMPS is more likely going to be designed by someone competent and tested to avoid all kinds of screwups, like tripping the breaker. While audiophile monoblocks... probably not. That said, as long as the amp has inrush current protection a.k.a. soft start as mentioned in prior posts, you're good.

Additionally, SMPS, compared to 60Hz power supplies, they use much smaller capacitances and transformers = much smaller energy storage = $$$ savings which is the point for their popularity. So by this nature it helps against tripping the breaker, too.
 
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wwenze

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I have been power monitoring my 2 six channel Buckeye 502mp Amps recently. When turned on 1 six channel 500mp amp draws 78 watts and after about 30 seconds drops t0 72watts. While playing a very loud movie neither amp ever exceeded 80 watts draw. The efficiency of these class D’s are pretty amazing. Nothing more than turning on an 75 watt light bulb.
6m4u20.jpg
 

tomtoo

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Maybe a littel off topic regarding class a/d. But older ciruit breakers tend to trip earlier. So if they are old, replacing them with new ones could help.
 

Willem

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To be clear, the 1000 watt seems to be the power they draw rather than the output power which seems to be 300 watt. With class D that difference is far smaller.
 
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Charles_b

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Maybe a littel off topic regarding class a/d. But older ciruit breakers tend to trip earlier. So if they are old, replacing them with new ones could help.
I live with my girlfriend's parents in a really old house (not properly insulated and single pane windows!). She said that the house was rewired in the early 90s. The fuse box regularly trips for vacuum cleaners etc. Trying to convince her parents to update the house is an uphill battle. Perhaps if I offer to pay to get the electrics updated, it will go a little smoother but not much. I think they are scared of change.
The plan for us is to convert the basement into a living space. It was an uphill battle just to decide on the location of a shed which, once completed, will house all of the Aladdin's cave of rusty screws and old bits of wood that the basement contains (did I mention they are hoarders?).
 

tomtoo

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I live with my girlfriend's parents in a really old house (not properly insulated and single pane windows!). She said that the house was rewired in the early 90s. The fuse box regularly trips for vacuum cleaners etc. Trying to convince her parents to update the house is an uphill battle. Perhaps if I offer to pay to get the electrics updated, it will go a little smoother but not much. I think they are scared of change.
The plan for us is to convert the basement into a living space. It was an uphill battle just to decide on the location of a shed which, once completed, will house all of the Aladdin's cave of rusty screws and old bits of wood that the basement contains (did I mention they are hoarders?).

I see the problem. Keep it in minde couse that tripping behavior gets worse over time. This things are not made to get used as a switch often. They enjoy to brake after a while.

Awai from that i would guess that the switch on current from class d is lower, couse they usually use switching psu. Switching PSU have usually smaller transformers and lower cap values what could reduce switch on current. But i not realy know.
 
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kiwifi

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The circuit breaker tripping is caused by inrush current as the power supply smoothing capacitors charge up. If you power the amps from a decent sized uninterruptible power supply (UPS), then that inrush current will be supplied by the batteries in the UPS at powerup. Once the inrush is over the UPS will switch back to passing the AC supply.
 

PeterOo

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I live with my girlfriend's parents in a really old house (not properly insulated and single pane windows!). She said that the house was rewired in the early 90s. The fuse box regularly trips for vacuum cleaners etc. Trying to convince her parents to update the house is an uphill battle. Perhaps if I offer to pay to get the electrics updated, it will go a little smoother but not much. I think they are scared of change.
The plan for us is to convert the basement into a living space. It was an uphill battle just to decide on the location of a shed which, once completed, will house all of the Aladdin's cave of rusty screws and old bits of wood that the basement contains (did I mention they are hoarders?).
Sound like a new class D with SMPS would be your best option then. :)
Probably saves you money, saves you frustration, saves the planet and saves your relationship with your parents in law.
That just leaves the question which amp you should buy…
good luck!
 

dlaloum

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Your amplifier appears to make 300 watts RMS into 8 Ohms mono in Class A on 220 VAC:


That’s still a lot of juice.
Not quite... 100 W in "pure class A" into 8 ohm

otherwise 300W into 8 ohm, 600W into 4 ohm

So the Amp is a Class AB with very heavy Bias into Class A - so heavy that under 90% of circumstances, it would indeed be running in Class A!

Nice amp (and heater) - and very well regarded.

Why would you want to change amps? - Yes a Class-D will run cooler and use less power - but you will be hard pressed to find something better.... many sideways steps, but unlikely to find a step up. (and far more likely to find a step down!)

Power consumption (as opposed to power output) is 1000W rated - and it's a monoblock, so 2 x 1000W.

Yes you probably need appropriately rated circuit breakers, and preferably a higher current circuit with heavy duty cabling.
 

beren777

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Changing amps will cost less than updating the electrical, especially if he can sell his current gear to a pizza shop or something.
 
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Charles_b

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The circuit breaker tripping is caused by inrush current as the power supply smoothing capacitors charge up. If you power the amps from a decent sized uninterruptible power supply (UPS), then that inrush current will be supplied by the batteries in the UPS at powerup. Once the inrush is over the UPS will switch back to passing the AC supply.
I've not heard of a UPS before. That's possibly another option. Many thanks
 

beren777

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The circuit breaker tripping is caused by inrush current as the power supply smoothing capacitors charge up. If you power the amps from a decent sized uninterruptible power supply (UPS), then that inrush current will be supplied by the batteries in the UPS at powerup. Once the inrush is over the UPS will switch back to passing the AC supply.
If the surge demand is sufficient to trip a circuit breaker, the UPS isn't going to like it either.
 
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Charles_b

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Why would you want to change amps? - Yes a Class-D will run cooler and use less power - but you will be hard pressed to find something better.... many sideways steps, but unlikely to find a step up. (and far more likely to find a step down!)
Good question. Apart from constantly tripping the circuit breaker, they weigh 30kg each and are a nightmare to move. If for any reason, I had to take them for repair, my back would not thank me lugging them down the stairs.

I never considered that it may be hard to find amplifiers as good or better than they are-probably because they are 15-20 years old and I just presumed that newer stuff would sound better.

I'm quite new to the world of hifi (2 years or so). So far, I have only brought second hand (and have never been to a fancy hifi shop to listen to new products).
When buying new speakers (for example), I try to read reviews on them and then I will decide to buy a pair if someone is selling them locally to me. I have a speaker A/B selector box so I can switch between my old speakers and the speakers I purchased until I have decided which pair I like best. I then sell the pair I like the least. It's incredible how short audio memory is and that direct comparisons are the best way to decide on your preferred gear.
Its a shame I couldn't borrow a class D amplifier to compare it directly with my Vincents.
 

Prana Ferox

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I live with my girlfriend's parents in a really old house (not properly insulated and single pane windows!). She said that the house was rewired in the early 90s. The fuse box regularly trips for vacuum cleaners etc. Trying to convince her parents to update the house is an uphill battle. Perhaps if I offer to pay to get the electrics updated, it will go a little smoother but not much. I think they are scared of change.
The plan for us is to convert the basement into a living space. It was an uphill battle just to decide on the location of a shed which, once completed, will house all of the Aladdin's cave of rusty screws and old bits of wood that the basement contains (did I mention they are hoarders?).

If you move into your in-laws' basement, every battle is going to be uphill
 

dlaloum

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Good question. Apart from constantly tripping the circuit breaker, they weigh 30kg each and are a nightmare to move. If for any reason, I had to take them for repair, my back would not thank me lugging them down the stairs.

I never considered that it may be hard to find amplifiers as good or better than they are-probably because they are 15-20 years old and I just presumed that newer stuff would sound better.

I'm quite new to the world of hifi (2 years or so). So far, I have only brought second hand (and have never been to a fancy hifi shop to listen to new products).
When buying new speakers (for example), I try to read reviews on them and then I will decide to buy a pair if someone is selling them locally to me. I have a speaker A/B selector box so I can switch between my old speakers and the speakers I purchased until I have decided which pair I like best. I then sell the pair I like the least. It's incredible how short audio memory is and that direct comparisons are the best way to decide on your preferred gear.
Its a shame I couldn't borrow a class D amplifier to compare it directly with my Vincents.

You do need to beware with regards to A/B testing - as little as 0.3db volume difference can trick the ear into thinking the louder alternative is "better" .... Those tiny level differences can also throw you off with regards to space, depth, detail, etc....

So level matching becomes very very critical, and very difficult.

An alternative is the "long term test" - replace your baseline kit with the new kit - use for at least 2 or 3 weeks - then see how you feel about them - are you picking up the same audible cues from favourite tracks? are some things easier to hear, or less easy? - Do you find yourself running things louder or softer? running softer can be a sign of gear having better micro detail, but it can also be a sign that at louder levels it is distorting, and gets annoying so you turn it down - a negative sign.

I decided to try the Crown XLS series pro amps some years back, it was not my first step into "Class-D" - the first steps were interesting, showed great promise, but were no match for my Quad Current Dumping amps (Quad 606 & earlier, upgraded 405's) - which were in turn superior to "beefy" flagship AV Receivers (Onkyo TX-SR876).

The Crown XLS2500's I got as an experiment (used, ex-pro/ Band use, only cost me US$250 each for a pair)... proved to be my best available amps - another step up from the Quad 606's.
They can put out (according to specs) 440W @ 8 ohm, 750W@4ohm, 1200W@2ohm - in stereo. And can also be bridged to run as monoblocks. (doubling power output).

I found the bridging them provided no benefit - using the pair to biamp my speakers may have some benefit (after much experimentation, I thought the bass went a bit deeper in bi amp mode, but it was sufficienty slight a difference to make it not worth the additional wiring complexity)

Things to keep in mind.... Within their optimal capability envelope, all halfway decent amps sound alike (!!!) - yes blasphemy to many...

It is when you drive them to the edge of their design envelope that they begin to misbehave and therefore "sound different" - my speakers drop down to 1.6ohm on the tweeter, and just below 3 ohm on the woofer - that means a lot of amps are pushed into a zone outside of where they are "comfortable". Loads of amps run out of current on these speakers, and then they get "flustered" in various ways.

The Quad 606's maintained their composure (they are very well behaved amps!) - but at 2ohm their power is well down at circa 90W .... where in theory if they were not constrained, they should be providing circa560W !! In theory the perfect amp would double power output in W from 8 ohm to 4 ohm and again from 4 ohm to 2 ohm.... in practice a bunch of design (and cost) constraints limit that doubling.... but as an indication... 90W@2ohm = 45W@4ohm = 22.5W @ 8ohm.... so roughly speaking the 606's, a 140W@8ohm amp design, were behaving as quite a nice 22.5W amp.

The point I am trying to make is that the amp and speakers form a speaker, you cannot take them in isolation, very few amps are over-engineered to the level that they can handle "any"/all speakers.

The Vincent's you have are an over-engineered design, by comparison to most amps - so they will do well with a much wider range of speakers than most. The Crown XLS series are also over-engineered, but from a different perspective - they are designed for a pro-audio or PA environment...

What I like about Class-D (and some traditional designs like the Quads) is that they run cool, and are quite efficient - That cool running characteristic is also typically an indicator of long service life - nothing kills solid state electronics faster than heat!

In your place, I would try to go out and find some Class-D amps to compare with... used. (which is what I did when I purchased the Crowns... I got them at a price where I knew I could flip them for at least what I paid for them, if not more)

And I would very much like the chance to listen to those Vincents.... I think they would probably do as good or better a job with my difficult speakers, as the Crowns do! - But would probably generate too much heat to take up long term residence with me.
 
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