Help With Tech Terms

[Sheilajeanne]

My technical knowledge when it comes to stereos and speakers is pretty basic. I know that speakers usually contain a woofer (for low pitches) and a tweeter (for highs)[unless this has now changed!] but when it comes to some of the posts on this forum I need someone to translate for me.

I am trying to understand how speakers have changed since the 1970s, and would like to understand just what avole is saying in this post:

Speaker technology in terms of materials used and computer modelling may have moved on, but, withe the exception of active speakers, any change in sound has more to do with current tastes than any technological change. Fast and forward is what suits AV best, and it's AV that is calling the shots.

The one area where things have changed is in amplification. Digital technology and the Class D amp has really caused one of the two great revolutions.

The other, of course, is network streaming and DACs, but that has little to do with vinyl.

What is an active speaker? From the context, it sounds like it is not just referring to one that is turned on and producing sound.

What is 'fast and forward' in terms of sound quality, and what is AV? I used to use that to refer to 'audio visual' but I don't think that's what the poster was referring to.

What is a Class D amp? Network streaming? (I know what that is when it refers to computers, but not audio technology) DACs?

And, more basically, why are current speakers so much smaller than speakers in the '70s?

I have done a fair bit of reading on the VE forum since joining, and am learning quite a bit. I could browse this site for hours trying to find answers to my questions but I have a business to run, and I don't have that sort of time.

Thank you for any help you can give me. I'm sure if one of you wandered onto one of the dog forums I usually frequent, you, too, would be baffled by abbreviations and terms like WL, SL, mal, KKl1, koer and easty-westy to list just a few!

[rhomanski]

Avole would be best to explain what he means, but I will try.
I'm not sure what active means but I think A/V means surround sound which needs to be in your face with explosions and such. Not so much with accuracy, so the sound is muddied with music somewhat.
Class D amp refers to the different types of amplifiers. Class A means the transistors are conducting at all times. Class A/B or push/ pull, means the transistors are conducting half the time, when one shuts off the other takes over, and so forth.
Network streaming refers to digitized music stored on one computer and can be accessed from any computer in the network either at work or in your own home wherever the network happens to be.
The term DAC stands for Digital to Audio Convertors. The most expensive and popular at this time are Burr/Brown. That will change as improvements are made to the technology.
And the reason speakers are smaller today is because of subwoofers. They actually are not smaller just split up into more boxes allowing people to hide the biggest box somewhere in the room. Also the trend recently has been to go with more drivers that are smaller. Instead of one 12 inch speaker they put 4 6 inch speakers in the cabinet. The thing to remember is that sound is moving air the less area of the speakers the less air is moved. So the only way to maintain air flow and reduce cabinet size is to make smaller but more speakers or split them into more boxes. Hope this helps.

Regards,

Ron.

[satanfriendly]

Sheilajeanne you are not alone when it comes to the world of terminology and abreviations etc. Are not the most of us?

Nicely put though Ron.

It is something I have often thought about, but is there anyone else who thinks the site would benefit from having a glossary of terminology/abreviations etc used in vinyl and HiFi?

Not a section for great debates, threads and the occasional argumentative stance (but we don't really do we? We just get passionate over opinions), but somewhere for a little educational material.

Anyone else a taker? JaS?

[Alec124c41]

AV is audio/video, or home theatre.
An active speaker is one with an amplifier built into it.
And I like those big old speakers from the '70s!

Cheers,
Alec

[bauzace50]

@Sheilajeanne,

Agreed, most abbreviations are lost on me, too. (LOL= laughing out loud, had been lost on me for a couple of years). FS= For Sale.

DAC= usually means Digital To Analog Converter. This is a circuit needed in CD players, where the pure digital signal from the CD reader is converted into analog form. This is needed for enabling the amplifier to handle it on the way to the speaker. Most CD players have it built-in. But upscale players have output jacks with the digital signal to be converted into analog by your own independent Converter with upscale specifications and price, and an opportunity to spend money on some exotic cable to go between them.

Active speaker= Alec got this one first (speaker designed with its own dedicated amplifier inside the cabinet) It usually contains its own dedicated crossover, plus any controls the designer might include, such as tone control, on-off switch, etc. I LOVE my Paradigm "Active/20" pair, no longer manufactured.

Size Of Speaker Cabinets= I prefer the compact ones (around 1.5 cubic foot?). But ones with huge refrigerator size from the past are fascinating. Patrician by Electro-Voice, Concert Grand (and Symphony) by Bozak, models by Altec-Lansing, and by JBL, and several Klipsch models come to mind. Electro-Voice marketed a 30-inch raw* woofer which needed a room-size cabinet (you had to add an extra room to the house, or incorporate it somehow to the attic, or the basement). (Size of speaker cabinet is usually determined by the design needs of the woofer driver, requiring a different thread for explanation).

* Raw Drivers= these are speaker units ( woofer, midrange, tweeter) sold individually without a cabinet or crossover. Usually sold this way for speaker builders.

Good luck,
bauzace50

[Sheilajeanne]

I'm now a fan of the larger speakers, too! The ones for my current stereo (a cheap Sony all-in-one) are about 8"x12". I replaced them with a pair of much larger Realistic speakers (about 12"x16") I recently got at an estate sale, and I am hearing lyrics on my CDs that I don't ever remember hearing before, even back when my hearing was more or less 'normal'! (Yes, I still have my old Beach Boys albums from the '60s plus a new CD or two, and their close harmony style of singing really helps show up flaws in your stereo system!) I've worn hearing aids since age 13, and ever since I got a cochlear implant in one ear two years ago, my current speakers sound like garbage! Ironically enough, being hearing impaired does not make you LESS discerning of good sound quality, it makes you MORE, especially if you have a good 'ear' for music!

[cats squirrel]

Note to JaS:

maybe a glossary would be useful.

[ighten]

Whilst not exactly active (you still need an external pair of amps) you can also have speakers where the crossover is removed(well not exactly physically).. I run a pair of Linn Katans and a pair of LK140 amps with activ crossovers installed..

The difference is like night and day .. Basically your using the amp to sort out the highs and lows and send them direct (Linn would say DireKt) to the right part of the speakers.

[Steerpike_jhb]

Strictly speaking, an active loudspeaker is one where the bass/mid/treble frequency splitting is done on the low-level line input signal, by an active (= using semiconductors) filter. Then two or three power amplifiers are used, one for each frequency band, for each speaker transducer (woofer, midrange, tweeter). A stand-alone power amplifier is not required as part of the playback setup.

But some incorrectly named "active loudspeakers" are conventional loudspeaker systems, with a passive crossver, and a single, full frequency range power amplfier inside the speaker cabinet. This is a much cheaper way of doing things.

[satanfriendly]

And so far the replies have said why a glossary would be a nice addition.

[JaS]

And so far the replies have said why a glossary would be a nice addition.

If there are any volunteers I can try to create a wiki type page for this purpose? I need to finish converting the main CMS software first, but I'm nearly there.

Regards,
JaS

[avole]

I warn you, JaS, it's no easy business. The software is the simple part, but getting people to agree to each definition is a different story.

[satanfriendly]

I would say a good 90% of definitions, abreviations etc are written in stone and it depends on how pedantic you may choose to be. Take it in its simplest form without adding technical thoughts, proofs etc and I don't see it being a tall order.

[avole]

Do you think so? There's three different definitions of active speakers on this thread already, and none of them are technically correct.

Perhaps the best thing is for you to volunteer