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Is the Berg Forte HP too HP?
- Thread starter MultiScaleMale
- Start date
I’m sorry that I ever mentioned anything about Berg. I will not ever again.
I think some people doesn't know that power stage is always wide open (connected to PSU rails), and volume control is done by input gain to that stage (= master volume).
Are you strong enough to crush an egg? Do you crush eggs every time you pick them up to put them in storage after you buy them?
I rest my case.
Ok, a bit flippant, so try this: Most amps that are nominally rated for a particular speaker power might get stressed when pushed hard, but that can make them more likely to destroy a speaker. Distortion kills tweeters, and bass drivers can get pushed to the point of mechanical failure well before they reach full electrical limits, especially when the rough sound of many hard-driven amps is masking more subtle sounds of a driver under physical stress. A cleaner sound makes it more likely that stress will be heard before it gets bad. A more powerful amp running at reduced power will be more efficient, last longer, and be less likely to fail in ways that will kill speakers, even in the case of lesser amps.
If a 50W amp fails badly enough it can kill a 100W speaker, tweeter OR bass driver. Dead short in a semiconductor, dumping the reserve in a PSU capacitor through the speaker coil, can be enough to pop the cone out of the basket. With a clean and strong amp, this is a much less likely event.
I rest my case.
Ok, a bit flippant, so try this: Most amps that are nominally rated for a particular speaker power might get stressed when pushed hard, but that can make them more likely to destroy a speaker. Distortion kills tweeters, and bass drivers can get pushed to the point of mechanical failure well before they reach full electrical limits, especially when the rough sound of many hard-driven amps is masking more subtle sounds of a driver under physical stress. A cleaner sound makes it more likely that stress will be heard before it gets bad. A more powerful amp running at reduced power will be more efficient, last longer, and be less likely to fail in ways that will kill speakers, even in the case of lesser amps.
If a 50W amp fails badly enough it can kill a 100W speaker, tweeter OR bass driver. Dead short in a semiconductor, dumping the reserve in a PSU capacitor through the speaker coil, can be enough to pop the cone out of the basket. With a clean and strong amp, this is a much less likely event.
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I've started the first number of the set with the amp in standby, forgot to plug in the cabs and started playing the wrong number, but I don't recall anyone, not even me, "accidentally" changing any of my settings. I recon the odds of that happening are as likely as me being hit by a meteorite while riding a tandem and wearing a tutu.
Then again, I'm usually gigging with more watts in the cabs than I am in the amp. That was also true when I had my Forte HP.
Then again, I'm usually gigging with more watts in the cabs than I am in the amp. That was also true when I had my Forte HP.
Jim Bergantino
Commercial User
Tough crowd! ;-). No worries here. Hopefully I didn’t come across disrespectful. I was only trying to help you and others understand gain structure. I think it’s safe to say this thread has outlived its usefulness, even by TB standards, LOL!
I use a Super Twin cab and sometimes think about getting a 1200 watt amp like the HP, just for the extra bounce and dynamics. I can give it that much but the rack system isn't as practical. I tell myself the 700 watts I'm getting is loud enough.
This is not about Berg, but about using a high wattage amp with a cab which can’t handle the amp full rated power. Substitute Berg with any other vendor who makes a high powered amp and the same concept applies. I think Post #20 about being afraid to drive a high horsepower vehicle because the gas pedal might stick is relevant.
Being familiar with both amp and cab, setting input gain and master volume appropriately, and using your ears to detect signs of distress should prevent damage. Common sense would say running with all knobs wide open with no oversight is a recipe for disaster. One other consideration to reduce the risk of an accident might be not to exceed an rms power ratio of 2:1. For example, I use a 400 watt 8-ohm 112 with a Forte HP which is capable of 600 watts rms into 8 ohms. The amp can put out 1.5 times the cab’s rated power. With input gain at about 1:30 and master volume at 11:00 that cab is being pushed and sounds full but is not in distress. If the 112 was only 4-ohms I wouldn’t use it because the margin for error is too close.
Another consideration is whether the cab can handle full rated power without farting out and how the EQ is set. A weak cab with lows boosted and no high pass filter to protect the driver won’t fare well. The HP, to its credit, has an adjustable HPF. If someone doesn’t know the behavior and limits of their gear the safe thing would be to use an amp which puts out less than what their cab can handle - kind of like having a governor on a go-kart to prevent someone from driving too fast. It should be safe but won’t have the dynamics and fullness of a well-run high performance system.
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My point was that at 1200W there aren't a lot of cabs out there that can handle 1200W, bigger cabs tend to be 4 ohm. The feature set of the amp in question would be nice with lower wattage, but I'm afraid of watts and sports cars. Anyways, not an issue any longer. Thx.
Ignore the sarcasm. I have Barefaced cabs that would be a perfect match I guess. Keep the thoughts rolling.
Who has a BAmp and a HP...? Do you feel a difference if you dont have to play extra loud ? ie does the extra headroom come into play if you arent pushing the amp past 11oclock?
Who has a BAmp and a HP...? Do you feel a difference if you dont have to play extra loud ? ie does the extra headroom come into play if you arent pushing the amp past 11oclock?
The HP is an amp kind of built for a specific set of people: Those that need or prefer a lot of headroom/ power, and / or those that prefer to have flexibility with their setup since the amp can drive a 2ohm load all day. At least that’s my take on it. there are plenty of 8ohm cabs out there that are appropriate for the 750 watts the HP puts out at 8ohms. Plenty of choices of two, three, or even 4 cabs that are appropriate for the 1200 watts it puts out at 2 ohms.
I wanted to be able to push the amp hard if I needed to without having to worry about cabs so I bought two barefaced cabs that won’t even blink at what the HP puts out.
Good question. Isn't it also likely that one of your knobs particularly the bass eq on your bass gets spun and all that happens? Could it happen in the din of too loud playing and you "torque" your speakers into damage? I might have experienced something like that or have seen a movie about it or someone told me they thought they knew someone who said their cousin heard someone say they had a dream about it.
(An Ag Preamp is a powerful thing.) (Speaker reconeing is a vital service.) We've never had this conversation.
- Feb 12, 2006
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- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Correct, and with a very large amp, if the player has an “accident” (say a cable becomes partially unplugged), there’s not as much margin between survivability and a damaged speaker. I do see this often enough that it’s a justifiable issue.
This is why I recommend adequate power handling for speakers, specifically to increase the odds of survivability.
Played a quiet gig yesterday with my forte hp into a couple of Barefaced 12s. Could have got away with just one cab and a less powerful amp easily enough but I have to say the sound was superb. The master was only on about nine o'clock but tone and spread was to die for. Similar thing has applied when I use my mesa 800+ into Barefaced Four 10 cab. Overkill maybe, but I prefer a clean sound with lots of headroom even in a quiet setting, and bot these rigs give it to me in spades. I have never had an issue in fifty odd years of playing through powerful amps, loud or quiet gigs.
I fried my share of woofers early on, mostly from trying to make a small cab do a larger cab's job. I never had any more problems after I got a 2x12.
I do worry a bit when I host jams; I never know what some other knucklehead might do with my rig in that situation. It's nice to have a "beater" amp for that application - just the right size and reasonably matched so they can't blow out the rig or the room.
Even better perhaps just to quit hosting jams.
I do worry a bit when I host jams; I never know what some other knucklehead might do with my rig in that situation. It's nice to have a "beater" amp for that application - just the right size and reasonably matched so they can't blow out the rig or the room.
Even better perhaps just to quit hosting jams.
I can say that even though I get sound that's "huge" enough for me using a 500 watt head to run a pair of 2x10 cabs (both rated 350 watts RMS), I get much more peace of mind having a limiter and/or an HPF that gives me a sort of electronic overwatch in case something upstream unplugs, goes clank, or falls over into something else... Beware of Miss Dancy-Pants in the front row, right?
Funny how gravity seldom takes a day off 'round here
Funny how gravity seldom takes a day off 'round here
