Bass Gear Mag issue 6

[lookiel]

Fair enough Aborgman,
but let's not forget that many real world users are fully satisfied with the output and general performance of the amp even compared to amps that put out their rated power.
And I'll take ''generally pretty honest'' to mean they lie the least of the bunch but they still fudge some specs

 

[Melvin7822]

I found the Markbass MoMark article interesting when comparing the output power of the 500, 600, and 800 W models. I was actually planning on getting the 600W, but I was surprised to see that it put out less continuous wattage than the 500 or 800 and that the 800 performed where I felt the 600 should have.

 

[Handyman]

I found the Markbass MoMark article interesting when comparing the output power of the 500, 600, and 800 W models. I was actually planning on getting the 600W, but I was surprised to see that it put out less continuous wattage than the 500 or 800 and that the 800 performed where I felt the 600 should have.

Its always surprising to see how many companies are "generous" with their power specs, TC has really taken this to a new level.

 

[makohund]

No, it (like mp3 compression) is all about the ability to remove parts of the signal (that eat up lots of power) because folks won't notice... and then once you remove those bits, you can boost the remaining signal much louder.

Um...

Lossy data compression and dynamic range compression share little in common other than one word in the name. Your description is mixing the two up. Yes, dynamic range compression squashes peaks allowing boosting of the rest. No, there is no bit removal, or throwing out what can't be heard/noticed, or anything else based on psychoacoustics happening at all.

Data compression is for squashing file sizes to be smaller. Dynamic range compression squashes audio signals.

It's basically just a complex multiband compression/limiting scheme. You could throw the same thing in front of any power amp and get the same "sounds like" more watts effect.

I think so.

If I had one, I'd try using it as a pre into a bigger power amp to see. Depends on where the "magic" happens in the signal chain, compared to the insert and the DI.

 

[tombowlus]

Tom...that is mighty good company to keep. Premier Guitar is the best Geetar porn on the newsstand. Modern Drummer is very good as well. Keep up the good work.

Thanks! And I tend to agree with you and hold both of those titles in very high regard.

 

[tombowlus]

That's certainly not how I read it, but we can let Tom comment on that.

No, he has it exactly right. The "A Closer Look" article on TC's Active Power Management does show when using an actual bass signal to test the amps, the RH450 didn't hit the same peaks as the other "500-watt" head, but it put out more after the peaks.

 

[aborgman]

Fair enough Aborgman,
but let's not forget that many real world users are fully satisfied with the output and general performance of the amp even compared to amps that put out their rated power.

Absolutely - and that is why folks shouldn't look at only output power. Heck, I play a 50W Ampeg B18.

And I'll take ''generally pretty honest'' to mean they lie the least of the bunch but they still fudge some specs

I, as of yet, haven't tested an Ampeg amp (SS or tube) that didn't meet the advertised power specs. In fact, every single one of them I've tested has done a touch better than published specs for power. My B-18 will hit 53-55W at rail.

 

[aborgman]

Um...

Lossy data compression and dynamic range compression share little in common other than one word in the name. Your description is mixing the two up. Yes, dynamic range compression squashes peaks allowing boosting of the rest. No, there is no bit removal, or throwing out what can't be heard/noticed

Yes, there is "bit" removal (bit as in piece, not bit as in digital bit) - they drastically roll off the low and high end... and the reason they can roll off that low end? They're throwing out what most won't notice missing.

Data compression is for squashing file sizes to be smaller. Data range compression squashes audio signals.

All lossy compression (whether data size, dynamic range, or frequency spectral content) distorts the signal (by definition).

If I had one, I'd try using it as a pre into a bigger power amp to see. Depends on where the "magic" happens in the signal chain, compared to the insert and the DI.

I'd be interested to see - because for most folks, it's a good way to achieve more apparent volume.

 

[Handyman]

No, he has it exactly right. The "A Closer Look" article on TC's Active Power Management does show when using an actual bass signal to test the amps, the RH450 didn't hit the same peaks as the other "500-watt" head, but it put out more after the peaks.

But wouldn't this be true for any power amp with a similar compressor stuck in front of it?

 

[makohund]

That's certainly not how I read it, but we can let Tom comment on that.

Fair enough.

I'm going mostly from the "From The Bench" article near the end of the mag, that gives numbers while putting it up head to head against a proper (but unnamed) 450W amp.

With test signals, the unnamed amp puts out more power at the transient, and only at the transient, all the way up to the point where the main signal is only 2.5dB below the transient. (At which point the TC can no longer keep up with the bigger amp.)

Immediately following the transient, the RH450 matches it at minimum, and is often putting out more. And with an actual bass signal, the TC put out more everywhere, except those transients.

Kinda cheating I guess, but It boils down to how good does it manage sound, despite not fully powering those transients. Whether one can tell the difference, or not.

I don't know. Haven't heard one yet.

 

[aborgman]

But wouldn't this be true for any power amp with a similar compressor stuck in front of it?

Yes.

The revolutionary thing here isn't the idea of increasing average power through compression - it appears to the quality/transparency/sophistication of the compression/limiting.

 

[makohund]

Yes, there is "bit" removal (bit as in piece, not bit as in digital bit)

Well... ok then, for certain values of "bit", lol.

they drastically roll off the low and high end... and the reason they can roll off that low end? They're throwing out what most won't notice missing.

Who is "they"? TC? MP3? Fraunhofer? I honestly am not sure what you are saying there, because talking about simply rolling off highs and lows for compression purposes doesn't really fit any of them.

All lossy compression (whether data size, dynamic range, or frequency spectral content) distorts the signal (by definition).

In different ways, via different methods, based on completely different priciples.

Dynamic range compression is like squishing a spring. Take a linear curve and reduce it's height, which also happens to shorten it. Compression achieved via simple and mild distortion.

Lossy data compression is more like blasting something full of holes in an intelligent fashion that reduces mass and volume, while retaining the ability to be reconstructed on the fly into a reasonable represention (to whichever senses) of the original. Compression achieved via complex and significant removal.

I'd be interested to see - because for most folks, it's a good way to achieve more apparent volume.

Yes, and not just apparent volume. Possibly higher average wattage, higher dB, SPL, blah blah. Real volume. If they can do it transparently... that's pretty cool. If.

 

[bottomzone]

TC Electronics must be doing something right-Nathan East just became an endorser.

‪Nathan East talks about his Blacksmith‬‏ - YouTube

A Groove is a Terrible Thing to Waste!

 

[JHAz]

On one hand, yeah. But I think you could probably tell from listening to it.

That seems to be the nifty part of the trick... doing something like that without sounding like it.

Look at their background... a lot of signal processing gear. I don't think that is a coincidence. They should build a bass preamp.

(Edited to include quote)

Maybe you could tell by a-bing it, but modern compressors in my experience willb e pretty transparent up to somewhere around 6 to 10 dB "off the top." Not saying what TC has done isn't somewhat different, just that it's still just compression/limiting.

 

[JHAz]

Um...

Lossy data compression and dynamic range compression share little in common other than one word in the name. Your description is mixing the two up. Yes, dynamic range compression squashes peaks allowing boosting of the rest. No, there is no bit removal, or throwing out what can't be heard/noticed, or anything else based on psychoacoustics happening at all.

Data compression is for squashing file sizes to be smaller. Data range compression squashes audio signals.

+1m exceot its dynamic range compression. If it is lossy, then everybody who listens to any commercial recorded music other than classical, or to the radio, is listening to highly lossy material. In the modern loudness war days, mastering involves squeezing maybe 20 dB of dynamic range out of the music. A lot of that stuff I don't like, but judiciously done, compression of an instrument or an entire mix can be at least musically appropriate, if not utterly transparent.

It's fun to fool around with compressors and see when, with a particular compressor and a particular signal, you start to hear differences. With single band compression, at some point, it starts to change the tonality of the instrument or mix. While the compressor/limiter used was had its own sound signature, as I understand it, the piano on Lady Madonna and lots of other Beatles recordings is an example of intentionally "screwing up" the sound via compression. You can tell it's a piano, but you also can tell you won't ever walk up to a piano and play it and get a sound exactly like that out of it . . .

Sorry to fall so far off topic.

 

[makohund]

+1m exceot its dynamic range compression.

Yes, that's a typo/edit failure there... there is no "data range compression".

Unfortunate place for it too...

 

[JimmyM]

I agree with this but was trying to say that maybe we should focus on the technical achievement instead of blacklisting the company.
Besides, c'mon, who doesn't lie in the MI industry?
A watt is a watt is a watt for sure, but is there any one given standard for measuring them between manufacturers?
I do not believe so.
Cab power handling, same BS from pretty much everybody.
And for the record it's not psychoacoustics, the articles deserve to be read and understood.

Trust me, I'm as against cab power handling specs being wrong as I am this.

 

[JimmyM]

TC Electronics must be doing something right-Nathan East just became an endorser.

‪Nathan East talks about his Blacksmith‬‏ - YouTube

A Groove is a Terrible Thing to Waste!

Victor Wooten has his own line of $150 AC cords coming out too, but that doesn't mean they're not snake oil.

 

[makohund]

Trust me, I'm as against cab power handling specs being wrong as I am this.

Speaking of "wrong", check this out. The "Active Power Management" pdf linked at the bottom of the page.

[Invalid or Expired Link Removed]

Learn all about transistor watts, vs tube watts, vs perceived watts.

Try not to scream. It does hurt.

Cool products. Nifty engineering. But geez... where'd they dig up the carnies and hucksters running the marketing department?

 

[tombowlus]

But wouldn't this be true for any power amp with a similar compressor stuck in front of it?

Perhaps, provided that the compressor really was "similar." I'm not the Technical Editor, but I recall Tom Lees telling me that the TC SpectraComp really had a lot of cool things going on and that TC was doing things with their compression/expansion/limiting that he didn't really see anyone else doing.

But on a basic level, yes, I think that some good compression, intelligently applied, could limit the peaks and bring up the valleys.