What Amplifier Specifications Do You Feel Is Beneficial?

[NKBassman]

So I'm sitting at my desk pondering some thoughts for an update of specifications provided, and while there are a ton of possible specs. to include I think many of them are virtually meaningless to the overwhelming majority of players. Of course there are some important ones as well.

Now's your opportunity to state your opinions as to what an "ideal" amplifier spec. sheet should contain. As ideas come up, I may wish to discuss them to be sure we are on the same page.

The one thing I am not going to accept are disrespectful posts however, and this is not (yet another) class D amp debate as the class of amp does not matter for this discussion.

EQ plots would be outstanding, but details on frequency centers, etc would be great.

 

[agedhorse]

I can understand that. I often see these specs quoted with PA equipment. It makes sense there since they are mostly designed to not impart a particular color. (Ok, some recording consoles are famous for the sound they do impart.) So i can see where this will be hard with instrument amps that are designed to color the tone in some way.

In fact, it's almost impossible. This is where the modelling amp algorithms are getting away from the real world performance of the actual products they are emulating. This is changing, but nowhere near as fast as I would have expected. While there are some good emulations and models, there are also a lot or really awful ones.

 

[agedhorse]

EQ plots would be outstanding, but details on frequency centers, etc would be great.

We already provide information on centers (and range of centers) plus cut/boost data. What in a plot would be more useful, or how should it be presented?

(I do in fact already generate sweep plots of many functions while fine tuning the feel of a control, but frankly without being able to relate it to something else, it's just a series of curves)

 

[petrus61]

Folks, out of respect to the OP, let's focus on his original question: What amp SPECS matter to you? This is not about features.

I'll leave now.

 

[Jeff Scott]

Not in any particular order:

Setting of EQ controls for ~ flat frequency response of the amp
Input impedance of all inputs
FTC style power output (if this is still relevant; do FTC ratings still exist, like they were for stereo amplifiers of yore?) at 8/4/etc. Ohms
Tonality (this one will be difficult to pin down )
Feature set - EQ specs, input output capabilities, etc.)
Dimensions (chassis only, and including knobs, handles, messiah, feet, etc.) and weight
Rackmount-ability (yes - no)
Accessories included

Edit: spelling

 

[MVE]

From how high you can drop it onto concrete and how many ounces of beer before failure.

Seriously, something like the falling on concrete spec would really help give an idea how well put together something is.

 

[Jeff Scott]

This is kind of where the pondering started, there are additional specs that might be important but there is also the potential to get so buried in the specs that they become meaningless (or worse, confusing) to those seeking information.

Better to be too comprehensive than too skimpy. Those that don't care about the specs won't be reading them, anyway. Those that do read them will appreciate the information provided.

 

[rodl2005]

I look for watts (power) in RMS but possibly total (burst ??) output might be handy too...for many ppl think that a 300w amp only puts out that. ..totally.
I'm far from an electronics fella. . But might this help some understanding what their particular amp might be capable of?

 

[somebrains]

I want my Electric Blue with 800-watt 5-string gig capable power.
EQ defeat, flexible DI, FX defeat and loop options.
Semi-parametric EQ.
Voicing is fine, but defeatable.
A "true flat" option of some sort would be good.

No matter what is produced, not everyone is going to be happy.

I want to play it, record with it, feed a PA with it.

 

[brianrost]

True RMS wattage at all impedances, with THD specified. The corner frequencies for the EQ bands and any boost/cut switches.

 

[joel406]

A 1000 watt subway with HPF, sweepable mids, individual mid volume control. FX loop of course. Hybrid amp with voicing control. Stuff like head phone jack and aux inputs aren't important to me but others may find them useful. Multi channel could be nice with a programmable foot switch. And a built in effects section with online upgradabilty. Stuff like overdrive, chorus and flange as well as other cool effects. Slave output for amp stacking. DI of course with both post and pre eq. Tuner built into footswitch. Programmable tuner that is.

If I sit and keep thinking this post will become rediculous.

 

[MarkA]

I would love to see a scope reading (if that's the right term) of the amp with all eq controls at noon. If the response is not basically flat at those settings (e.g. if it has a baked-in eq curve like the GK heads), I'd also like to see what knob settings give the closest to flat response on the particular amp in question...

I would be interested in this information.

Honest THD specs. Headroom means a lot to me.

I like this. Perhaps stated as:

1 Gigawatt RMS @ 8 Ohms @ 0.1% THD
1.10 Gigawatts RMS @ 8 Ohms @ 1% THD
1.21 Gigawatts RMS @ 8 Ohms @ 10% THD (or whatever you think relevant -- I would be more interested in the first two numbers).

If the preamp section is designed intentionally to have a certain amount of distortion, perhaps that could be considered separately.

I would also like to know about phase deviation. I think group delay and phase coherence is related to the punch and dynamics of an amp.

This is something I'm interested in, but I don't know enough about it to know what to look for, numerically. Qualitatively, I notice that some amps, apart from how they're voiced, sound more coherent and focused than others and have better pitch definition. I've noticed, too, that some EQs maintain this (sense of coherent, focused sound) much better than others as you move the controls off of center. I listen for this when I try an amp and I ask about it if I get to talk to a knowledgeable player who knows the amp or to the designer of an amp/preamp but, at this stage of my understanding, if you gave me figures for group delay and phase deviation for a bunch of different amps, I wouldn't have much idea of how to interpret them meaningfully.

That's not to say that BFunk or others couldn't make good use of the spec, or that they shouldn't have it available to them.

In addition to what specs would be meaningful to include, it might be worthwhile to consider how and where you'd include them. This subject has come up before, in various forms, in various threads. A common theme has been that it's possible for a manufacturer to shoot themselves in the foot if they provide too many (or honest-but-not-marketing-friendly) specs -- either they'll be overwhelming for the average consumer or your 630 Watts @ 0.1% THD won't compare favorably with a competitor's 900 Watts* or another competitor's 1500 Watts(!)**.

* @ 20% THD
* Burst @ unspecified THD​

Phase deviation and group delay probably aren't going to make it into the adverts or onto the box of the amp (nor probably %THD, for that matter). Maybe not even into the general specs you see when you click on an amp's webpage. Having a "detailed specs" page available -- on the web -- maybe at the back of the online manual? -- and at the back of the printed product manual -- not sure you can have too much information available there.

Maybe I'm wrong -- maybe it would make for more headaches (more time spent answering questions from people armed with a little knowledge) for you -- but I'm always interested in knowing more.

You could put the more esoteric specs toward the end (maybe in slightly smaller print ) or in a separate table.

 

[agedhorse]

From how high you can drop it onto concrete and how many ounces of beer before failure.

Seriously, something like the falling on concrete spec would really help give an idea how well put together something is.

There used to be a tongue in cheek spec, back when esoteric distortions were "popular"T.I.M. and such. This was E.R.D., standing for elastic rebound distortion... how high an amp would bounce when dropped onto a concrete floor from 6 feet. It was used when folks who had no idea what they were talking about were insisting that they knew more than they understood. They would always know about E.R.D, and which amps were the greatest and which amps sucked and how it related to spacial sound field and the other Audiophile BS that was popular at the time. All the while, those who knew what was going on could watch the impending crash and burn when it was explained.

 

[basscooker]

Not all companies list their HPF roll off, that's one.

I like the idea above about focusing a little on mechanical specs. Something like maybe a "G's rating" ? Something that can help you determine whether or not you just damaged the PCB mounts or put something inside at risk when your amp fell.
Gauge of chassis material?
Cold and hot extremes where performance may be affected along with acceptable time recommendation at room temperature before use?

I'm reaching. Honestly , you already go pretty deep with your literature and customer service. There are other companies that should be looking to expand their spec info.

 

[agedhorse]

The THD spec isn't very useful when it's tightly integrated into the entire amp. This is the problem, how to extract the important specs from the unimportant ones. In play-tests, where I can add and monitor harmonic percentages, most players, given their choice, preferred THD (made up of a series of harmonics) levels far higher than I would have expected, feeling that the amp sounded richer and more full, more organic.

This is a complex topic, and frankly the details really get into the proprietary aspects of a particular product's design. Just note that most players would find .1% THD (and even 1% and more) sterile and lifeless, not very finger-friendly either.

 

[agedhorse]

Not all companies list their HPF roll off, that's one.

I like the idea above about focusing a little on mechanical specs. Something like maybe a "G's rating" ? Something that can help you determine whether or not you just damaged the PCB mounts or put something inside at risk when your amp fell.
Gauge of chassis material?
Cold and hot extremes where performance may be affected along with acceptable time recommendation at room temperature before use?

I'm reaching. Honestly , you already go pretty deep with your literature and customer service. There are other companies that should be looking to expand their spec info.

Interesting stuff... the problem with the fall resistance is where it lands. ALL of these amps have vulnerable controls, falling on a control is going to cause damage regardless of other aspects of the packaging.

The thermal performance is worth looking into a bit more however...

 

[basscooker]

The thermal performance is worth looking into a bit more however...

Lots of gear "lives" in trailers, trunks, back seats and garages in all sorts of weather. Could be useful info if there are any performance changes under temperature extremes.

For example, some upholstery vinyl has a "cold crack" spec if it's likely to be used for car or motorcycle seats.

 

[Nev375]

I like to see charts and graphs. Frequency response and EQ centers, etc... Visual information means more to me than numbers.

Even before I understood how to read that stuff it seemed more professional and I have more confidence in manufacturers that put that data out there.

I remember back when Crutchfield published catalogs for home and car audio there was a lot of educational info included about what different specs meant and how to compare products. I'd like to see manufacturers start doing stuff like that.

 

[Downunderwonder]

In the absence of an industry standard I propose a full 2 second power output of nominal cleanness 60hz to 200hz.

Aka Trace Watts.

 

[Hoochie Coochie Man]

I think some of the more esoteric specifications that some people have mentioned are overkill. Few people will know what they mean, and would not be likely to be published by other manufacturers so you could make a comparison between various amplifiers. Anything beyond the basic specifications found in the D800+ owners manual would not help me predict how it sounds, or how it performs in various circumstances. I ether like how it sounds, or I don't.