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Posts posted by SteinbergerHack

  1. 5 hours ago, AJ6stringsting said:

    12 ga. , an ETA power conditioner and the it feeds into my Monster 2500 power conditioner ....never failed to give me surge protection and kills any RFI interference.

    ETA makes some decent stuff - the EPD8LR would be a really good choice for just about any rack application.

    • Like 1
  2. 22 hours ago, daddymack said:

    which is why it is just plain dumb to haul stacks around when a 15-20W combo amp will get the job done

    True, though if you want really crisp clean sounds, you may well need more power.  What's counter-intuitive for beginners is that the "loud" and "heavy" high-gain guitar sounds are actually easier to get with a low-power amp than a high-power amp (while retaining proper cochlear geometry and limiting discussions with local law enforcement).

    22 hours ago, daddymack said:

    Steinberg's numbers are 'theoretical'...no one is building amps anywhere near those values, and for a number of good reasons.

    Well, not just theoretical - that's the actual reality of what can be done with a single standard 120VAC power input.

    I would also say that while there are no guitar amps being built at those power levels, there are plenty of PA amps at very high power ranges, and they are in fact limited by the available line power.  Here's a spec sheet that shows output ratings based on line Voltage and current:


  3. On 3/12/2020 at 7:10 AM, mbengs1 said:

    I know 100 and 120 watts is the standard. I also heard of 150 watt heads like the mesa triple rec. but what's the maximum no. of watts an amp can have and why is that the maximum? 

    After having chuckled my way through reading this thread, I finally realized that there is a reasonably accurate answer to this question, and one that is based on the basics of physics, power amp design efficiencies and electrical distribution practices:

    At 120VAC (North American power), the largest common circuit capacity is 20 Amps.  Thus, the theoretical maximum power that can come from a single 120VAC power outlet is 2,400 Watts.

    For a Class A amp @ 50% efficiency, the maximum you could get from a single 120VAC outlet would be 1,200 Watts.

    For a class B amp @ 75% efficiency, the maximum you could get would be 1,800 Watts.

    For a class D amp @ 90% efficiency, you could get very close to 2,160 Watts.


    Problem solved.  Do I get a cookie?

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  4. 3 hours ago, Phil O'Keefe said:

    Also, make sure any power conditioner you're considering has good surge protection too - power surges can destroy gear. 

    On that note:

    I've been in the electrical equipment industry since 1990, and hold a patent for a high-end surge protective device design. Pardon the long post, but there's a lot of pure garbage that gets stated about "power conditioners" and surge suppressors, and I think it's helpful to get down to the core facts of what they can and cannot do.

    A "power conditioner" doesn't really protect your equipment in any way.  The majority of them are no more than a 60 Hz filter, with perhaps a bit of surge protection.  Unless you are dealing with a noise issue from another ill-behaving load on the same circuit (like a neon sign or failing refrigerator/fluorescent light ballast) , they really are just electronic jewelry.  Surge protectors, however, can provide real value in preventing transient over-Voltage events from damaging your gear or shortening its life.

    There are two key performance factors that tell you how a SPD (Surge Protective Device) will operate in the real world, and a third that will give you a sense of how long it will live. The first two are the clamping Voltage, i.e., what is the highest Voltage that the SPD will let through to your equipment when it attempts to clamp a surge event. The second is the Peak kA rating, which determines how much transient energy the SPD can absorb without failing to clamp. These are required test values for any SPD that meets the UL SPD standard (1449, 4th edition). Peak current is sometimes called Nominal Discharge Current, and clamping Voltage is sometimes referred to as VPR (Voltage Performance Rating).

    The third value is the total amount of energy that the device can absorb before its useful life is over. Most SPD are based on MOVs, which are sacrificial devices that lose some capacity every time they absorb a transient. A higher "Joule rating" indicates the total amount of energy that the device can take, which gives an indication of how long it will last in normal use. Be careful, though, as a high Joule rating means nothing if the device doesn't have a high enough Peak kA or low enough clamping Voltage rating to protect your equipment.

    I like the fact that both Furman and TrippLite give clear, honest ratings information for their devices. It allows you to really compare what they do. The trouble is that many other manufacturers do not, so it can be difficult to get a really solid, fair comparison.

    So, have a look at this product:

    Look at the spec page, and go down to the bottom, where it shows the peak impulse current, rated at 12,000 Amps. This is actually a pretty reasonable rating compared to most inexpensive "surge strips", as it is double the 6kA that is required for the VPR testing under UL1449. It's limited to 150 Joules so it's not a long-life device, but it will take a reasonable hit before it lets anything through to your gear. The real problem, though, is that the only protection modes are line-to-neutral. A transient that is line-to-ground would not be clamped inside the device, and would force surge current to travel through the neutral-to-ground bonding link either in your equipment or in the service panel. Not a common occurrence, but not a good outcome.

    Now, compare to this product:
    https://www.furmanpower.com/product/20a-advanced-power-conditioner-wsmp-no-lights-9-outlets-1ru-10ft-cord-P-8 PRO C

    Note that it doesn't use MOVs, so there is no Joule rating - it should absorb surges throughout its useful life. Trouble is, its initial clamping value is only 3,000 A, and it's max is 6.5 kA - roughly half of the other device. It's about tradeoffs, and the trade-off here is that a relatively moderate transient event would pass through this device and get to your gear.

    Now, what would I recommend? Something more like this:

    Have a look at the spec sheet. Clamping Voltage of 140VRMS. Peak current of 96 kA, which is more than a standard 120/240 VAC panelboard can handle. Joule capacity of 3840. UL1449 approved. Note that it also include Line-to-Ground and Neutral-to-Ground protection modes, as well. This is a serious SPD that actually does the job, and will keep doing it for a long time.

    There's a lot of snake oil in this part of the electrical industry, along with some reasonably good products that are just over-priced for what they deliver. The key to not getting ripped off is to understand the specs and use them to understand what the various products will really do.

    Full disclosure - I used to run the engineering team for a company that made SPDs (not one of the ones I have mentioned here). I've moved on to another part of the industry, so there's no conflict of interest with this post.

    Finally, as Phil noted above, your power cables should be as short and as thick as you can get them.  I won't let anything smaller than 14 gauge anywhere in my gear, and I prefer 12 gauge.  As a comparison, the NEC (electrical code) won't let you wire any 120VAC service in any house or commercial building with anything less than 14 gauge wire, and higher gauges are required for long runs (to meet Voltage drop requirements).  12 gauge is required for 20 Amp circuits.


    Hope this helps....

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  5. What do you mean by "take away from tone"? 

    Changing the voicing of an amp (tone) is not the same thing as degrading measurable performance.

    Generally speaking, any time you introduce an external loop of any sort, you add some noise into the system, and you may well reduce the overall dynamic range available.  That said, a guitar amp running with anything other than an ultra-clean gain structure has already lost a lot of dynamic range.

    Here's the real underlying question that (I think) you are asking.  If you took a short jumper cable and patched through the FX loop with no other devices in the path, would it change the sound?  My experience is that switchable loops can change the sound very, very slightly; non-switchable loops do not, as there is no circuitry added.

    Put another way, the change you hear in your sound is nearly all a result of the things you put in the loop, not the fact that the amp has a loop.

    FWIW, my Bogner has a switchable FX loop.  I have a patch on my FX rack for "Digital Bypass" which has no actual FX programmed and unity gain, but running through everything in the rack.  When I am setting levels, I use this patch to make sure everything is balanced by setting it so that I can switch the FX loop in and out and have no change in the output sound (and see that every FX unit has the right gain setting, no clipping, etc.).

    • Thanks 1
  6. 29 minutes ago, Phil O'Keefe said:

    I started on reeds, so theory and reading notation came along with that. Then I learned bass clef when I started playing bass. But my eyes are not as good as my ears, so I tend to rely on my hearing and memory more - once I’ve read through and heard something a couple of times, the sheet music becomes an occasional reference rather than something I need to rely on. 

    Same here - I started on violin.

    • Like 1
  7. 5 minutes ago, gismo recording said:

    That's supposed to be about guitar players.

    It's been my experience that bass players in general are more knowledgeable about music theory than guitarists.

    I think that's because a reasonable number of bass players start out learning upright/classical bass, then transition to electric.  It seems that a LOT of guitar players start out by learning the "cowboy chords" and completely skip the basic sheet music/sight reading progression.

    • Like 1
  8. 3 minutes ago, flemtone said:

    Q:  How do you get a bass player to turn down?

    A:  Put sheet music in front of him.


    -As a bass player, I say....bring it on, ya pansies.  :love:

    Bass is relatively easy to sight read in comparison to guitar.  That said, there are a lot of non-readers in the rock world......

    • Like 1
  9. 2 minutes ago, Phil O'Keefe said:

    Guy + keyboard = Guy and three cats. 

    I can see it fine, and apparently so can AOF. What are you viewing the forum with ATM?  Phone? Tablet? Computer? What browser / OS?


    Win10 - Firefox - Dell laptop

    Can't see it with Internet Exploder 11 either.

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