old school watts v new age watts-fact or fiction?

[iconic]

I'm laid up in bed with bad ears at the moment so been trawling thru threads on yamaha b100 heads and naturaly other old 70's and 80's amps get talked about too.

Plenty of verbal tennis of what's better etc but a recurring comment seems to be that older amps, with 'only' 100 watts seem loud compared to todays offerings, and that some of the specs on the newer gear maybe a little optimistic...my 180 watt ashdown does sound feeble compared to my pv tnt rated at 165 watts.

So whats the real storey?

Cheers guys

[Jazz Ad]

I think it's all in the voicing.
Given limited power, amplifiers had to find ways to get you heard. TNT and TKO amps used a simple trick. Boost the hell out of low mids and cut lows they couldn't properly amplify anyway.
These days people like transparent tones, it takes a lot more power to get these to push through the mix.

[alexclaber]

That it isn't electrical watts which matter - it's acoustic watts, and they depend on real sensitivity (not bs marketing sensitivity) and real power handling (excursion limited, not thermal) as well as electrical watts.

Lots of reading here to explain this stuff: Barefaced Bass - "But this goes to eleven?"

and here: Barefaced Bass - Technical Information

[alexclaber]

And regarding power rating specs and actual real world power, note the following:

If two amps are both rated at the same power output then one will usually sound louder than the other if:

(These are EQ curve, filtering, compression and 'tone' issues - these points are all regarding increased perceived loudness without any difference in actual power.)

1. It has less bottom
2. It has more midrange
3. It has more treble
4. It has a less clean sound but the dirt is pleasing to your ears
5. It has steep highpass filtering to avoid wasting power on subsonics
6. When it clips it clips in a more sonically pleasing manner
7. It has a good limiter which allows you to push it harder before clipping or unpleasant compression occurs
8. It has in-built compression which increases the averageeak level ratio

(These are specification and power section issues - these points relate to amplifiers actually producing more power in the real world)

1. Its power was rated at a lower %THD
2. It has greater current delivery reserve
3. It can deliver more peak power
4. It is better at handling reactive loads

All comparisons need to be done with a very high spec loudspeaker otherwise its non-linearities at high power will lead you astray. Change the cab and all bets are off - sensitivity makes a HUGE difference to dB out.

[iconic]

Wow, great answer, cheers

[alexclaber]

No problem! I don't know what that green smiley with its tongue out is doing in point 8 though...

[lomo]

Originally Posted by alexclaber

No problem! I don't know what that green smiley with its tongue out is doing in point 8 though...

That, Good Sir, is no ordinary smiley, but rather a smiling Mutant Ninja Turtle

[alexclaber]

Originally Posted by lomo

That, Good Sir, is no ordinary smiley, but rather a smiling Mutant Ninja Turtle

Kowabunga!

[bertbass666]

Back in the day there were also loud and quiet watts. A Marshall 100w was certainly louder than a Selmer 100w and an AC30 was, and still is, pretty loud as well.

[BassmanPaul]

Originally Posted by bertbass666

Back in the day there were also loud and quiet watts. A Marshall 100w was certainly louder than a Selmer 100w and an AC30 was, and still is, pretty loud as well.

Now you are talking gain structure. The output stages of the Selmer and the Marshall are very similar. The 30W AC30 is obviously less powerful than either!

[JimmyM]

Alex, no doubt you tried to type average : peak ratio, but you didn't include spaces, so you created a smiley.

[Ric Vice]

Originally Posted by iconic

I'm laid up in bed with bad ears at the moment so been trawling thru threads on yamaha b100 heads and naturaly other old 70's and 80's amps get talked about too.

...my 180 watt ashdown does sound feeble compared to my pv tnt rated at 165 watts.

So whats the real storey?

Cheers guys

Just my take, but the B-15 cabinets were designed to work with the lower wattage that head could produce. Thus, to my ears a my "25 watt" B-15 NC sounds nearly as loud as my GK200RCB, but that's not the case, as the GK has nearly three times the power. If I plug the RCB into the same Portaflex
B-15N cabinet it's definitely louder, even at 8 ohms.

Ric

[ulynch]

Originally Posted by alexclaber

And regarding power rating specs and actual real world power, note the following:

If two amps are both rated at the same power output then one will usually sound louder than the other if:

(These are EQ curve, filtering, compression and 'tone' issues - these points are all regarding increased perceived loudness without any difference in actual power.)

1. It has less bottom
2. It has more midrange
3. It has more treble
4. It has a less clean sound but the dirt is pleasing to your ears
5. It has steep highpass filtering to avoid wasting power on subsonics
6. When it clips it clips in a more sonically pleasing manner
7. It has a good limiter which allows you to push it harder before clipping or unpleasant compression occurs
8. It has in-built compression which increases the averageeak level ratio

(These are specification and power section issues - these points relate to amplifiers actually producing more power in the real world)

1. Its power was rated at a lower %THD
2. It has greater current delivery reserve
3. It can deliver more peak power
4. It is better at handling reactive loads

All comparisons need to be done with a very high spec loudspeaker otherwise its non-linearities at high power will lead you astray. Change the cab and all bets are off - sensitivity makes a HUGE difference to dB out.

This is a great, detailed answer to the question. Could we also add to this, the ratio at which the "volume" knob increases the perceived output? It seems some volume knobs reach higher levels earlier in their range than others. Hence, my Carvin BX500 at 3 is as loud as a 1000w Ampeg at 8.

[will33]

Originally Posted by ulynch

This is a great, detailed answer to the question. Could we also add to this, the ratio at which the "volume" knob increases the perceived output? It seems some volume knobs reach higher levels earlier in their range than others. Hence, my Carvin BX500 at 3 is as loud as a 1000w Ampeg at 8.

Yes, many volume knobs are anything but even throughout their range. I've played a few where you had to turn them up quite a ways to get to loud, these would be more linear pots. I've played many more where the entire useable range was contained in the first half of the dial with nothing but distorted crap and speakers trying to jump out of their boxes past that, these would be quite non-linear. You also have to consider how hot a signal you're putting in the front of the amp. Active basses, pedals and especially pedals that act as preamps before the input all give you less range of motion in the knobs. In my case it was all passive bass--->cord--->amp input so yeah, the numbers on the dial mean nothing. Some will do this on purpose so when you're comparing amps on the sales floor you'll get the feeling like "wow, this one's as loud on 3 as that one is on 7", all the while both amps are putting out roughly the same juice.

[billfitzmaurice]

Originally Posted by BassmanPaul

Now you are talking gain structure. The output stages of the Selmer and the Marshall are very similar. The 30W AC30 is obviously less powerful than either!

The AC30 may have less power but it's still hellaciously loud, easily as loud as any 2x12 out there. It's all in the gain structure and the voicing, not power. The same applied to many of the old bass amps, and the cabs as well. A pair of K140s or EVM15Bs would deliver a lot of dBs with not that many watts. What they wouldn't deliver was a lot of deep low end, but we didn't care. We couldn't hear a lot of deep low end on our KLH stereos or AM car radios, so we didn't miss not having it from our amps.

[BassmanPaul]

I couldn't agree more about the AC30 Bill. VOX was the brand that we all aspired to own back in the day. Using an AC30B, open back cabinet and all, I filled the Silver Blades ice rink in Liverpool, England. The thing was walking across the stage but wasn't distorting. Superb amp for it's time. I still get a fond feeling when I see an AC30 on stage!

[billfitzmaurice]

Originally Posted by BassmanPaul

I couldn't agree more about the AC30 Bill. VOX was the brand that we all aspired to own back in the day. Using an AC30B, open back cabinet and all, I filled the Silver Blades ice rink in Liverpool, England. The thing was walking across the stage but wasn't distorting. Superb amp for it's time. I still get a fond feeling when I see an AC30 on stage!

We never considered the AC30 as a contender, because it was only 30 watts, and you could get a lot more watts for a lot less money from Fender. Sound familiar?
I never saw AC30s back in the day, only starting in the 90s did they seem to become popular here.

[will33]

Well, I am not of the experience to speak first hand of what it was "back in the day", but I can tell you, every AC30 rig I've heard can easily bumrush a Marshall rig of equivilent power and size. A more fair comparison might be pitting one against a Marshall rig of twice the powwr and size....just to make things even.

[chuck3]

so ... I've been working with Genz Benz and LittleMark hybrid and/or SS heads that can deliver 600 and 500 watts into 4 ohms, respectively, or so they say.

To enter the all tube world, I picked up used a Traynor YBA 200 which is all tubes 200 into 4 ohms. I A-B'd all this stuff to death into a 4 ohm Genz Benz Neox 2x12 cab that I know to be reliable.

I couldn't get the Traynor to keep from breaking up somewhat (not in a good way) at higher volumes. So far I haven't played out with the Traynor for that reason.

Are the watts in an all tube head the same as the watts in a hybrid or SS head? The whole deal seems very different to me. But I went from using, like a Fender Bassman, to taking some time off, then coming back to Genz Benz etc.

So I'm confused. It's possible the Traynor is just not a very good unit, but I doubt that. I think there are adjustments needed for an all tube head that I'm not making.

[BogeyBass]

Originally Posted by iconic

Plenty of verbal tennis of what's better etc but a recurring comment seems to be that older amps, with 'only' 100 watts seem loud compared to todays offerings, and that some of the specs on the newer gear maybe a little optimistic...my 180 watt ashdown does sound feeble compared to my pv tnt rated at 165 watts.
So whats the real story?

the 180 watt ashdown is most likely very overated and barely pushes 120 watts. The peavey most likely a few more watts with a slightly better power supply.

As far as late 60's early 70's solid states sounding "louder"
would be similar to what Alex mentioned as a amplfier having a pleasing distortion and sounding louder with more harmonics. similar to tube watts seeming louder because of pleasing harmonic distortion.

Early transistor amps used quasi complementary output stages. which used all NPN transistors. Compared to more modern output stages that use a matched pair of NPN and PNP transistors. High power PNP transistors in the late 60's were very expensive almost 3x more and actually performed poorly compared to lower cost NPN. Hence the reason for the quasi complementary output stage to take advantage of the cheaper NPN's. To make a long story short it is the most tube sounding solid state amp when driven into distortion. I have had many tube amps and my solid state Acoustic 370 (quasi complementary) will give many low wattage tube amps a good run for the money as far as tone and pleasing distortion. Another good example of the Quasi Complementary amps is the early Sunn Coliseum which has the same pleasing distortion, with a little more balls than a Acoustic since it had slightly higher power supply voltage. Anyhoo the yamaha B100 and B100II had quasi complementary output as well. little wimpy compared to the Sunn or Acoustic. But likewise if you run the B100 100watts into the large ported 2x15 it was designed for. It will keep up pretty good compared to early low watt tubers like a Sunn 200S, Ampeg V4B or Bassman 100 . Run it into a lossy 2x10 sounds like poo, run it into a 2x15 which has more sensitivity it will make some happy.