If the THD is disclosed, then it's not being dishonest, is it?
Seriously, you can make all the excuses you want, but you haven't said a single thing to convince me otherwise.
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True power output?
- Thread starter bassbrother666
- Start date
Seriously, you can make all the excuses you want, but you haven't said a single thing to convince me otherwise.
At least I hope the grammer is correct?TC is hiring political speechwriters to write their ad copy now?
You know my English isn't the best
Your grammar was fine!At least I hope the grammer is correct?
You know my English isn't the best
Sorry for my rude words. svt performance and tube watts isn't an appropriate topic here.
I don't feel I have (or have the like) to convince anybody. To me it's very interesting to see two signals in comparision (like shown above) and then take conclusions. The conclusions are somewhat contrary to "conventional" considerations, that's all of it.
Clearly we have distinct standards to evaluate power capability of an amplifier. And exactly at this point sometimes (or often) I'd wish a somewhat different standard that more involves typical characteristics of the application the amplifier is meant for. For example burst capability duration is measured with sine waves, but who the **** will ever strain in real practice an amplifier with sine bursts?
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No one is arguing that different things aren't important.
But TC said "RMS power: 450 watts."
That is a lie.
RMS and peak power have everything to do with the subject. The entire controversy is because the RH450's power rating, both peak and RMS, is not what TCE said it was.
Exactly.
It's not a perfect system, but TCE still used its terminology in describing the output of its amplifiers. Descriptions that turned out to have nothing in common with the real numbers.
- Feb 12, 2006
- 61,045
- 5
- 220,998
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
If you guys understood how complicated it is to balance the power response of the amplifier with the feel back to the player, you would not be arguing this topic the way you are.
For example, when analyzing the dynamic response of some of the most popular and desirable bass amps on the market, it's critical to understand what is happening in terms of the raw power, the dynamics versus time (attack & sustain envelopes), what is happening during this period in terms of amplitude versus frequency, what is happening with regard to symmetry, how symmetrical the linearity is, what distortion components are being created (and in what proportion), dynamics density, in addition to some of the simpler things.
Sometimes, when it comes to developing products that sound right and feel right to a particular type of player (Jimmy liking the sound and feel of Ampeg is a good example), how do you describe a very, very complex set of parameters in a way that makes any sense to a normal, reasonable player (specifically not an engineering type like me)? I remember the days when some of these iconic old products were being designed, I recall tweaking and tuning a design with a player playing away and with the player(s) making the performance choices without even considering what the technical measurement might be. If you use top players to guide the design process and tune the parameters, you get a top grade amp (for that type of player preference). As a recent example, the Genz Benz Streamliner and Shuttle share a similar power amp platform but perform completely different (by design) because they were developed for completely different player preferences, styles and ultimately, applications. The harmonics management and even the dynamics management are very different between the two.
Note that I am not commenting on, not will I comment on any other manufacturer's product, other than to say that it's very much more complicated than most of you here might imagine.
For example, when analyzing the dynamic response of some of the most popular and desirable bass amps on the market, it's critical to understand what is happening in terms of the raw power, the dynamics versus time (attack & sustain envelopes), what is happening during this period in terms of amplitude versus frequency, what is happening with regard to symmetry, how symmetrical the linearity is, what distortion components are being created (and in what proportion), dynamics density, in addition to some of the simpler things.
Sometimes, when it comes to developing products that sound right and feel right to a particular type of player (Jimmy liking the sound and feel of Ampeg is a good example), how do you describe a very, very complex set of parameters in a way that makes any sense to a normal, reasonable player (specifically not an engineering type like me)? I remember the days when some of these iconic old products were being designed, I recall tweaking and tuning a design with a player playing away and with the player(s) making the performance choices without even considering what the technical measurement might be. If you use top players to guide the design process and tune the parameters, you get a top grade amp (for that type of player preference). As a recent example, the Genz Benz Streamliner and Shuttle share a similar power amp platform but perform completely different (by design) because they were developed for completely different player preferences, styles and ultimately, applications. The harmonics management and even the dynamics management are very different between the two.
Note that I am not commenting on, not will I comment on any other manufacturer's product, other than to say that it's very much more complicated than most of you here might imagine.
We know that it's complicated, AgedHorse.
Still, when a manufacturer claims that their product has a measurable specification, and then it can't hit that, I think that's a problem. The product may be a very nice product, but they should not claim that it does something that it does not actually do, or even come close to doing. Even if they think it's a standard of dubious value that shouldn't matter, they shouldn't use it at all instead of using it dishonestly.
Still, when a manufacturer claims that their product has a measurable specification, and then it can't hit that, I think that's a problem. The product may be a very nice product, but they should not claim that it does something that it does not actually do, or even come close to doing. Even if they think it's a standard of dubious value that shouldn't matter, they shouldn't use it at all instead of using it dishonestly.
IMO the most problem is hanging around with (continous) sine waves instead of more practical signals.
It makes blind to essential things going on under the hood.
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I'm curious, can you point out some specific example of TCE defining their label of “450 watts” as something other than (generically) saying “450 watts” (i.e., where they said "RMS power: 450 watts")? I had an RH450 from very close to when they first came out. I had the original owner’s manual, which the specifications you’d expect to be as specific as they got, and my recollection (and I’m 99%+ certain of it) was that it didn’t define the rating as being in conformity with any particular measurement or standard.
The specifications now read “Power Module Rating: 450W”, still without reference to a particular standard, but it does include reference to an explanation of APM.
Personally, I reach a point that I recognize that I don’t have a dog in the fight; TCE doesn’t pay me…I don’t own or have any interest in the company or its (or Behringer’s) future. I’m a consumer who bought and used a great amp for a bit over 3 years. It served me well, never once had an issue of any kind, and produced sound that I liked and that received numerous compliments (including some number of people deciding to buy one after hear/trying mine). Aside from the learning curve on the semi parametric EQ (which I would have had with any amp with the same operation), on multiple levels, it met and often exceeded my needs, expectations and hopes in practical use. It did that relative to its price, competition I was able to sample, and the label of “450 watts.” Its features set my expectations and wants currently.
I do end up wondering what others’ interest in this is. The most vocal critics clearly have fixed viewpoints on the amp and the company…if anyone’s interest in this would be to have saved someone like me from going through the experience I had, I’d say “Thanks, but no thanks.”
Look for an amp that meets UL1711
No silly burst rating, were talking 250 hours of full rated real power at <1% distortion
It's meant for fire protection systems, but heck, shouldn't an amp be able to meet this spec, easy
No silly burst rating, were talking 250 hours of full rated real power at <1% distortion
It's meant for fire protection systems, but heck, shouldn't an amp be able to meet this spec, easy
- Feb 12, 2006
- 61,045
- 5
- 220,998
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
Look for an amp that meets UL1711
No silly burst rating, were talking 250 hours of full rated real power at <1% distortion
It's meant for fire protection systems, but heck, shouldn't an amp be able to meet this spec, easy
Wait a minute seamonkey, uou have to remember that the amps designed for this purpose are also rated for a power bandwidth of 800Hz - 4kHz, and I recall the THD+N at <20%. Going from memory, as I don't have a subscription to this particular UL standard, there is also a duty cycle that's included in the test that is consistent with the voice evac. standards. I also recall that the amp must perform at 24 volts DC (or the inverter equiv. which must also be listed) and deliver this spec as well... So the standard is REALLY unsuited for a bass guitar amplifier.
You can't arbitrarily apply a spec. without understanding the details behind the spec. and this spec is for a really unrelated application.
UL1711 is intended for Amplifiers for Fire Protective Signaling Systems...
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From a players perspective, a power output rating doesn't mean a lot. Use the wattage rating as a guide to tell you roughly what group the amp is in, nothing more. Specs that aren't presented on a uniform playing field can't be meaningfully compared so why even try. You can't believe all the marketing copy that you read. They put them out there to get you in the door and try their product.
If the amp sounds good and does what you need, that's all that is important.
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From a players perspective, a power output rating doesn't mean a lot. Use the wattage rating as a guide to tell you roughly what group the amp is in, nothing more. Specs that aren't presented on a uniform playing field can't be meaningfully compared so why even try. You can't believe all the marketing copy that you read. They put them out there to get you in the door and try their product.
If the amp sounds good and does what you need, that's all that is important.
If one were to rate the power in FTC
<Some wattage>
4Ω FTC 0.1% THD
20 Hz–20 kHz after preconditioning
And show that it can do this over hours and hours and hours
Then it should also pass the UL 1711 requirements as tested by a certified UL lab.
Most amps would probably drop to 1/8th to 1/16th their current marketing ratings, except of course for a few if the top name power amplifier brands that actually now publish FTC ratings. (very few)
I don't want to see the government step in for "Musical" amplifier markets like they have for Consumer markets, but it's gone totally crazy lately and if manufacturers don't get a handle on it - who knows?
<Some wattage>
4Ω FTC 0.1% THD
20 Hz–20 kHz after preconditioning
And show that it can do this over hours and hours and hours
Then it should also pass the UL 1711 requirements as tested by a certified UL lab.
Most amps would probably drop to 1/8th to 1/16th their current marketing ratings, except of course for a few if the top name power amplifier brands that actually now publish FTC ratings. (very few)
I don't want to see the government step in for "Musical" amplifier markets like they have for Consumer markets, but it's gone totally crazy lately and if manufacturers don't get a handle on it - who knows?
- Feb 12, 2006
- 61,045
- 5
- 220,998
- Disclosures
- Development Engineer-Mesa Boogie, Development Engineer-Genzler (pedals), Product Support-Genz Benz
May sound good on the surface but how does it relate to bass amps or MI amps or even pro audio amps? In fact, it does a pretty poor job relating to the intended HI FI amps really.
The 1/3-power pre-conditioning period has absolutely nothing to do with today's class D amps and SMPS. This part of the test was developed because it coincided with roughly the maximum power DISSIPATION of a LINEAR (AB or B, not G or H) output stage, and was intended to insure that the thermal capability of the amp was at least reasonable, BUT it allowed for repeated cycling during the preconditioning period which would be an absurd thing to expect a bass player to accept in their amp. Then there was the continuous measurement period (which also allowed for cycling) as long as it passed the cumulative total. Pretty absurd when it comes to a bass amp.
Regarding the UL 1711, that's an even more absurd test because it has NOTHING AT ALL do do with the low frequency performance of an amp, and continuous power over hours and hours is absurd because there is not a single bass guitar application that involves continuous power for hour upon hour, nor is there a single bass speaker that would qualify to being (ab)used by an amp rated in this way and survive as well. Who cares how a bass amp would perform in a voice evac. system, and if you knew more about the standards, you would quickly see that it would be impossible to design a bass amplifier that would pass UL 1711 for a whole host of reasons completely unrelated to bass guitar. Should all bass amps be forced to operate on back-up battery power? Well, when you get into the bigger amps, you will quickly see that the size of the 24 volt cable and the boost converter would double the size of every compact bass amp out there today. Is that a step forward, or is it a step backwards because somebody doesn't understand what they are proposing?
You need to understand a whole lot more about the subject before proposing an absurd and unrelated standard. It's like some government programs intended to help but in the end are so screwed up that they do nothing but hurt, and hurt bad.
What I would suggest are a couple of items that would more accurately characterize the performance, such as:
Peak power, based on the peak voltage of the sine wave after say 100mSec (this would characterize the dynamic response after 5 cycles of 50Hz)
RMS power, based on the RMS voltage of the sine wave after say 100mSec, area under the curve method at a specified %THD (this would characterize the average power under hard use conditions)
Thermal capacity, at all rated impedances, based on the number of minutes at 1/8, 1/4, 1/3 and 1/2-power (this would show the thermal performance under different duty cycle conditions, the longer it performs, the more robust the design, but the user can choose how robust they need, or are willing to pay for. 1/2-power is so heavily compressed as to be barely useable, for reference.
Current capability, how much current the amp can source or sink to the load (this would show how well the amp is likely to perform in sub-nominal impedance loads)
Now these are all very real indicators of real world performance as they relate to a real bass player, playing a real bass, in the real world. There are plenty more of these metrics as well. Continuous power for hours on end, and running fire voice evac. systems are anything but real world tests.
What is not needed is another single manufacturer pushing and promoting special pleading of why the specs they push are the all amp makers should follow
FTC works and protects consumers
Musicians need protection because it has got out of hand. Totally crazy
I'm not going to purchase ul1711 doc. The points I read I like is an amp maker rates their amp power and frequency response, and has to be able to provide this for 240 hours
Skip the battery requirements if they exist. Skip voltage line rating just use full rated power
At full rated frequency response
TCE and LabGrumpen were and are now part of the same company. They know how to build and rate amps. It's a shame they tried to pull special pleading on their bass amps.
It's your money, ask for honest specs
FTC works and protects consumers
Musicians need protection because it has got out of hand. Totally crazy
I'm not going to purchase ul1711 doc. The points I read I like is an amp maker rates their amp power and frequency response, and has to be able to provide this for 240 hours
Skip the battery requirements if they exist. Skip voltage line rating just use full rated power
At full rated frequency response
TCE and LabGrumpen were and are now part of the same company. They know how to build and rate amps. It's a shame they tried to pull special pleading on their bass amps.
It's your money, ask for honest specs
I remember Bob Lee talking about a project for unified, meaningful spec sheets amongst all builders but I can't find back the info.
Unless it is in the interest of the company selling the product, there isn't a lot of motivation to provide level playing field specs. Pro audio is a different story, it pays to be more honest.
There will always be companies that cheat and that will sway buyers over to those products. Competition and marketing forces things to go down hill from there.
