Ohms & Watts

[Mark Black]

In the end I think everything works (and lasts) best when the operator understands all of the gear and the relationships between all the bits. And then never run the thing at the edge of capability.

We wouldn't expect our cars to last long if we always had the gas pedal floored (though I see people on the freeway every day who don't seem to know or care about that).

I've known sound companies over the years who got pretty good results with what would probably be considered mediocre gear, and had it last a long time aside from the occasional random component failure or environmentally caused woes.

[bob p]

I always thought the best way to protect a speaker would be to make it so efficient that your ears would bleed before it overheated.

... and to use a number of those drivers in an array to limit the amount of work being done by each individual driver.

I like efficient speakers. But there certainly does seem to be a trend to move away from them with the modern bass amps.

I think the real issue is money, high efficiency drivers need precision engineering and expensive magnets, but Class-D power is cheap. The situation we have now is probably optimal in terms of SPL per dollar spent on gear, at least in terms of the sticker price. SPL per total cost of ownership might tell a different story.

On the amp side it's always been about money. The reason that tubes were abandoned in favor of SS components was often claimed to be about reliability, but it was really about reducing production cost. The same could be said for the incremental changes in SS amp design --rail-switching amps, for example, were adopted to increase operating efficiency and thereby reduce the parts cost associated with heat dissipation. Class-D amps are doing the same thing today. Imporoving thermal efficiency makes amps cheaper. It's hard to imagine that thermal efficiency will take us much farther, as the thermal efficiency of Class D is impressively high.

Reliability and TCO are looming questions that bother me. From my limited experience with Class D designs, there does seem to be a reliability issue. The amps are certainly cheap to produce, but they're often made out of proprietary chip-on-a-stick designs which can make them difficult if not impossible to service. We may have reached the point that a power amp is becoming a disposable/no-repair item. If that's the case than TCO is going to be high.

[bob p]

I think the real issue is money, high efficiency drivers need precision engineering and expensive magnets, ...

I hadn't really thought about it this way before, but I think you're right -- the reason that we're entering an era of high power Class D amps with inefficient speakers for bass amp applications is not only related to amplifier cost, it's also related to speaker manufacturing cost. It's certainly not entirely related to performance as the marketing teams are trying to convince us.

The marketing hype says that we need to embrace high power Class D amps and small tuned cabinets that have low efficiency because that's the way to obtain deep low frequency extension in a lightweight portable package. What they're not telling us is that low efficiency drivers are cheaper and easier to produce, so they're not worrying about precision speaker manufacturing or high efficiency now that amplifier power is so cheap.

What a surprise -- It's all about the bottom line.

What bugs me about this is the limited ability to service some of these designs. To me, rail switching amps don't look all that bad.

[km6xz]

The real cause for the race for power is sub-sonics became part of music a couple decades ago. Every fractional step lower increases the power exponentially. Sub bass was not part of music nor was it expected until recently. Habits and tastes change and with it was the move into incredibly inefficient acoustic energy generation running up against the lower hearing sensitivity of humans ate subsonic resulted in a 136db spl on a dance floor went from 50 watts to 50,000 watts being enough to get the job done.

It was habit change. Subsonics are not intrinsic to music and it was never written into the equation except as an occasional sound effect with 32 foot pipes in concert organs. Even in rock there was little energy below 80hz from the 50s on. There were many songs that relied on a strong rhythm but kick and open E strings were not recording fundamentals for many reasons, one was that it muddied things up, another was the lack of storage medium that could play it back without introducing tremendous distortion in the rest of the spectrum, and shorten playing time dramatically.
Variable track pitch was used to get longer playing time but bass heavy grooves had to be widened to provide the space for the wider deviations of cutting heads with constant velocity recording and playback. A bass heavy song could take up more width of the record than 3 light bass songs of the same duration. Couple that with the restrictions on AM broadcast frequency bandpass both regulatory and technical and the play back systems used by consumers of music.
A typical car radio, AM, in the 50s and 60s used 1-2.5 watts power amplifiers and used dash or rear deck mounted 6X9 oval speakers. The oval speaker was developed specifically for the shape of the space available in back of the windshield of both the rear deck and the dashboard, it was a shape that allowed the largest cross section in one direction and still fit. With all that power available, playing reasonably loud meant no bass was allowed. That was fine, the records did not have it and the AM radio could not transmit it if it was on the records. Who, from the mid 50s or early 60s, did not hear those drum and bass lines of the old Doo Wop groups or the Motown classics?
But the music relied on a strong bass component in the style of music. As long as the second harmonic and higher order harmonics were intacts, the brain filled in the missing fundamental from a harmonic series that inferred the fundamental. No one listing to the old music had any problem locking onto the rhythm as if the bottom WAS there. It was not missed or expected, and made vocal pop records intelligible at higher volumes with more noise(road noise-before air condition was common, record noise, AM broadcast noise, etc).
I was a frequent visitor to the 1960s dance halls in San Francisco where 5-10 bands would play at high levels, like Filmore, Carousel, Veteran's Mem, Warfield, Loading Zone, Family Dog etc and believe me, it was loud but there was no deep bass, subsonic so the systems were very low powered, 200 watts total in Fillmore, 120w at Family Dog. That was enough for handling the DR of belters like Janis Joplin, big bands like Sons of Champlin and Tower of Power, or rock/blues of the Dead, Elvin Bishop, or Jimi or the dozens of equally unique and later to be famous, bands of the neighborhood. No one complained or would have noticed something was missing from the sound, because the music and the expectations of the listeners were for the traditional range of playable notes. The CD, which eliminated the limitations of records and cassette tape, ushered in subsonics, more of a sound effect than anything else but a generation or two have come to expect power sensation below notated scales.
That demand for power by the speakers and amps trying to reproduce 20hz ballooned the cost and ability to stage modest priced concerts, and also lowered, in my opinion, the attractiveness of many styles of songs. Concerts do not work as well when vocals are needed to be 10 db louder just to get some distance from the overpowering subsonics, which in turn has destroyed vocalists being able to use dynamics in their story telling. Maybe a new generation will shun the physical sensation high that some get from subsonic stimulus so battery powered systems would be enough for play and performing. The addition of deep bass has changed song writing and I do not believe for the better. Maybe the attention being given to efficient use of energy will reduce the demand for extreme subsonic power. Global Warming or the added restrictions on wasted energy just might be a positive for music.
People ask me for recommendations for sound systems and I have to ask what bandpass as the first question because if they say 20-15k I say right off, they can't afford or haul it but if they can get by with 60-15k, they can, plus carry it in their car trunk and buy it for a month's salary. A club recently asked for a system design to replace their system since the DJs were complaining about not enough bottom. The funny thing was that the club had one of the consistently largest crowds. I listened to the system and I knew it from the perspective of the dance floor many a 3a.m. and liked the sound. My suggestion came as 3 options, one was to find less egocentric DJs because the crowd was voting with their wallets of where they liked best. 2 was to build a system that was clean and powerful to please the DJs but expect lease problems and legal problems, and spend $400,000, from which not one additional dollar(Ruble in this case) in income would result. Or, get a fat cheap high distortion powered sub and mount it 12 inched from the DJ inside the DJ booth.

[Steve Conner]

In a former life I used to produce drum'n'bass. I would actually run my basslines through a tube amp to add harmonics, and then filter out the subsonic content, to help it sound good on low-powered systems.

I have quite a few CDs where the engineer or mastering guy forgot to do that, and the woofers flap slowly in and out because of some subsonics that accidentally got in. Nothing more annoying, as you can't hear it, it just wastes amp power and could even make a tube stereo amp distort badly.

Clubs might have 50,000 watt systems, but if you're producing content for the Internet, it's quite possibly going to be listened to on a pair of shitty plastic computer speakers, or worse, laptop speakers! And the reality nowadays is that the Internet and social media is huge, so many would-be fans and gig promoters are going to decide whether they like you or not, based on what they hear through their crappy computer speakers.

So I still go for the overdriven tube bass, which can even bludgeon its way out of laptop speakers.

[Enzo]

Even in the old days, in the studio, they'd have the best sounding stuff, but when they mixed it all down, they always also had a pair of little 8" speakers. It wasn't enough the "real" tracks had a nice full sound, but it also had to sound OK coming out the car radio speakers and table radio speakers that most people listened to. Not only that, the stereo mix had to come together when played mono.

[Steve Conner]

Yup, the 'OrribleTone sound cubes or whatever they were called.

[km6xz]

5 inch speakers were used for that purpose, to check the mix on portable gear but also since they were close, were used for imaging reference. The big mains would be used in tracking and mixing but the stereo balance was hard to get a handle with big speakers in soffits 8 feet way, with a gigantic console in the way.
Small speakers an arm's length away were perfect for that however. Get up close to a couple, even bad speakers and the imaging will be better and more accurate than any room monitors. We started adding small bookshelf speakers in the near field also, mainly because in the marketing ploy that really worked, Yamaha gave dozens of their new bookshelf speakers to studios with requests to try them. Sure, 4 pair of free speakers was hard to turn down. They did serve a purpose in acting as a mid or near field with a little wider range than the industry standard Auratones. They were not as good for imaging since they had two drivers and were slightly further away.....imaging is poor with sources further than you can reach with your hand. But those photos of mixing session with those distinctive white cone NS-10s that album covers often had, turned the NS-10s into an big hit, with every demo studio buying them thinking they were the new reference standard. But they used them as room monitors for the whole mix and that mess them up more than they could have imagined. They started mixing bass heavy because they did not hear enough of it. The big room monitors kept us aware of the bass and tone so bottom did not dominate the way it did with the sudden new trend of small console mounted 2-ways that did not know they were turning the mix to mud. It helped their imaging but blew on tone balance.
We had a small FM transmitter and a AM broadcast transmitter so a mix could be listened to out in the car, in realistic car radio conditions. And the mix would also be checked by cassette tape, again, in the car. So the parking lot was a busy place during mix sessions, with people running out to check mix every 30 minutes or so. The mix could could also be checked on the compact stereo system in the accounting office, to get the realistic impression on a typical low cost apartment or dorm room system.
Now it is easier, ear buds are probably 80% of music listening. Mixes for clubs are not done in that phase or by the original producer at all so popular and rock music is mixed for one media, digital, and primarily for earbuds. FM is dead by 1992, AM died in the early 80s, and turned to talk and sports.

[Enzo]

I know more than one engineer who would hear a piece of music and remark, "That was mixed on NS-10s."

[Leo_Gnardo]

Yup, the 'OrribleTone sound cubes or whatever they were called.

Auratone = "Horror Tone". Idea #1: it's good to listen on a speaker that's representative of what people really have at home, a 3" "full range" inside the TV or clock radio, and Idea B: If you can get a mix to sound good on the small speaker, it will usually be terrific on the big speakers. Somewhere the "medium" speaker made its way to the studio's meter bridge, and that's when Yamaha's NS-10M became the world standard. Funny thing, I've never seen 'em used in a home stereo. But if you could get a mix that sounded terrific on these sorta "flat & uninvolving" speakers, it usually came out sounding even better on anything else.

Then there was the trend of placing a sheet of tissue over the NS10's tweeter. Ah but what kind of tissue is the "audiophile correct" item to place over that pesky "hyperactive" tweeter? There were even a couple of manufacturers that were making special holders for the tissue rig when Bob Clearmountain wrote a page-long disclaimer and that was published in Mix or Recording Engineer/Producer. "I did it in one studio, for one session, because that's what my ears told me needed to be done," is essentially what BC had to say. That everybody followed suit and now even arguing over what kind of tissue, he claimed, was a failure on their part to use their ears, their judgement, and instead create & follow a trend. (BTW the original tissue IIRC was Kimwipe, a lint free version of the common Kleenex.) All that and ... it's the lower frequencies, and how they're represented in a mix, that usually indicate the use of a small & inadequate studio monitor. When "alternate" NS-10's showed up, Tannoy, KRK, Genelec, even Peavey, etc, they had a bit more "boom & tizz" but still not the audio bandwidth of the big monitors. So an engineer/producer could mix to what he could hear, but still had to guess what's going on in the low frequency regions that are "out of band" for whatever small bookshelf is riding their meter bridges.

A customer recently gave me a copy of his otherwise well mixed blues-rock CD that had it's bass "center" down around 40-50 Hz. While it's a treat to hear some "sock" on my 15" JBL home speakers, I doubt the low end will appeal to most folks whose home systems & car systems too, are tuned to a "disco bass" about an octave higher. Like it or not, that's where most people's ears have settled as being a satisfying bass region. If there's not enough going on there, then "something's wrong."

[km6xz]

I think that developed a bit backwards. Listening on small speakers was not to optimise them, that was what $10k worth of room monitors built into the walls were for. We kept checking on small speakers to verify that we did not introduce something that worked great on the full range system but created a problem on the small monitors or car system. The mix was still built up on the room monitor. The AuraTones where not intended to sound good, near fields were for placement of elements in the image that close in speakers are excellent for.
The tissue thing came up for the same reason most fads came into being, just like the NS-10s selling by the ton. The magazines, particularly Mix, showed dimly light beauty shots of studios on the cover and Yamaha gave a batch of NS-10s to 8 studios which were not in the charts of the time and once a few photos were seen on album covers or Mix covers, they were suddenly the "gotta have" item for every studio that wasn't in that league. I never mixed on NS-10s but used them and Auratones frequently for safety checks, the same way but more frequently, as the car tape or FM listening.
Every time a product is associated with something people like, regardless of the contribution that product made, it is going to sell well simply because of that association. Tennis players earn more for carrying a certain racket than winning tournaments. NS-10s sold well because they showed up on meter bridges of studios that were doing well, even if the only reason they were there was Yamaha donated them. In an interview an engineer or producer mentions a particular mic was used on a vocal that did well on the charts and the next week the mic is a best seller. The mic had nothing to do with the success of the record, none, yet those who do not make real records of real songs for real distribution do not know that. They tend to try to duplicate everything used or mentioned during sessions of a favorite album. Same with guitar effects and amps. It is effective marketing but does not make better songs.

It was not just speakers, if a band was in which had an endorsement contract with an amp or string maker, there would be a truck pull up with a ton of the stuff. Mesa was the most "generous" it appeared, because they were relatively close and would bring lots of amps and never come get them. It was cheap advertising, a full page color spread was not as effective as a blurry photo of a producer or studio with NS-10s in the background. Now, advertizing is more sophisticated and product placement generates a substantial portion of the production budget for TV shows or millions on films. Conventional ads on TV and print do not work well now but ad agencies still talk clients into gigantic ad buys. The most effective influencers now are product placement/endorsements and spamming user review web sites. The NY Times used to make or break a book based on reviews and placement on their best seller list which was not the best selling.
Now, well corrodinated fake user reviews on Amazon can turn a book into a gigantic success. Any site that offers user reviews is highly manipulated. Why...it works. People believe reviewers they think are real people that are not. They tend not to believe high production value TV spots. A $10m ad buy on TV is not as effective as $10k worth of fake rave reviews.

[Enzo]

You...you mean... Geico doesn't REALLY have a lizard working for them. And Progressive doesn't REALLY have a diner waitress selling insurance?

When we were kids, riding around, we played a game, it involved spotting Volkswagen cars. But today the wife and I watch TV and play the "Product Placement" game. Same principal. The detective drinking a can of Coke at his desk. The police interview a lady in her home as she gets a large bag of Lays Potato Chips from her shopping bag. Chef Irvine drives up to a restaurant in his Lexus SUV and the camera pauses over the logo a few times. I notice as we watch the Today show in the mornings, they have a few segments where they go out and "visit" with the folks on the street. They have closeups, and every few seconds a wide shot of the crowd. Each time they go outside, on one of the wide shots we can count on a FedEx truck driving down the cross street in the center of the picture. They always get the Dean and DeLuca sign in the background when the anchors speak.

[bob p]

I don't mind if you say that Flo is fake, but don't go saying that the talking lizard isn't real. That would be like saying there is no Santa Claus.