How important is the efficiency of a speaker to you?


I went to an audio meeting recently and heard a couple of good sounding speakers. These speakers were not inexpensive and were well built. Problem is that they also require a very large ss amp upstream to drive them. Something that can push a lot of current, which pretty much rules out most low-mid ( maybe even high) powered tube amps. When I mentioned this to the person doing the demo, i was basically belittled, as he felt that the efficiency of a speaker is pretty much irrelevant ( well he would, as he is trying to sell these speakers). The speaker line is fairly well known to drop down to a very low impedance level in the bass regions. This requires an amp that is going to be $$$, as it has to not be bothered by the lowest impedances.

Personally, if I cannot make a speaker work with most tube amps on the market, or am forced to dig deeply into the pocketbook to own a huge ss amp upstream, this is a MAJOR negative to me with regards to the speaker in question ( whichever speaker that may be). So much so, that I will not entertain this design, regardless of SQ.

Your thoughts?

128x128daveyf

@atmasphere wrote

... it may interest you to know that high efficiency drivers, in particular woofers can be 10x more expensive than drivers of similar bandwidth and power handling that are not efficient. As an example the TAD 1602s (15", 97dB, Fs 22Hz) are typically $4000.00 each. Put a field coil into the mix and the driver gets even more expensive.

You’re referring to a boutique element of high efficiency drivers that aren’t representative of this segment. Low eff. drivers have their expensive iterations as well, and when you count in the typically larger size of high eff. drivers, bigger voice coils and more magnet material, not least from the more widely accessible pro sector, their pricing compared to low eff. "hi-fi" dittos is actually very fair. Most of these very expensive high eff. drivers are vintage designs of limited production, btw., and it’s not that the production tolerances here are somehow magically "tighter" to reflect and account for the higher pricing.

Tidbit: just going by specs the EV woofers of my main speakers share the 97dB and 22Hz Fs TAD numbers of yours (Fs 21Hz, "broken in"), and I’m guessing they’d have retailed for about 1/10 of $4,000.

I suspect the $4,000 price claimed is not real- likely seen by atmasphere  somewhere on the resale market because the product is long discontinued.   That price is not representative of what it really sold for back when it was made or what current drivers sell for that replaced it from TAD.  I know the distributor in the US.

 TAD DOES make expensive drivers, they are Japanese (Pioneer) but are used mostly in their own speakers or OEM in horn loaded systems.  Very good drivers for sure.  TAD was a good low distortion driver used regularly by George Ausperger in his large all horn designs which were quite popular in recording studios years ago.  Today, TAD is still used by folks that build these all horn loaded systems that echo those Asperger designs.  I hate the way they sound- high distortion and just loud.  Lower fidelity by today's standards.  They are common for hip hop where SPL matters on client playback.  Mixing still done on lower distortion direct radiators (we sold TImbaland ATC 100s for this exact purpose).

Many studios still have these TAD or JBL loaded horn systems in the wall- they do look cool and are part of the studio "vibe".  They were always used for the band to hear playback at higher SPL in the best possible fidelity (which is very low compared to modern hi fi or studio speakers).  SPL = excitement.  The trend now in studios is direct radiators, such as ATC, that favor low distortion so you can mix faster, worry less about translation and hear more details.  

It is interesting that the TAD 1602 drivers had very little test data or info available.   It does say the 1602"S" was a special version of it with shorter voice coil for lower distortion.  You would have read about that same short coil idea in the white paper from Billy Woodman I posted.   All the ATC studio and hi fi drivers use short coil long gap topologies for reduced harmonic distortion.

This is precisely what I am saying that efficiency is but one part of the picture as today short coil, venting, narrow gaps with precise coil fitment, flat wire coils, the right former material, etc is way more important when amps are relatively cheap.  These types of drivers are impossible to build by machine.  Hand made drivers is the way to get it done and everyone in the industry used to build their own: KEF, B+W, JBL, on and on.  Now, hardly anyone does this anymore as it's way too expensive, difficult to train people and environmentally challenging.  A small company cannot afford to build their own.  ATC is the last of the breed in the UK.  Everyone else has left and gone to China.

Brad      

Dear @lonemountain : Yes, today TAD speakers are not exactly high efficiency at 90db and are expensive but its sound quality level performance is excellent.

 

In the past Exclusive in Japan ( Pioneer ) had the 98db big  2401 Twin model obviously all TAD drivers and in Japan in those early 80's its retail japan price was 1,200,000 Yens and a direct competence to JBL and other USA speakers or from England as the Vitavox.

TAD today monitors for home audio are in the 85db efficiency and excellent performers too.

 

R.

@lonemountain  : Now I understand why for you is important but not so important the speaker efficiency issue. I visit your virtual system and seems to me that you are an audio distributor od low efficiency ATC speakers.

 

@phusis  "  the claim that high efficiency is necessarily and always bound to be attained "with a price," sonically speaking, is a fallacy. Typically it comes down to (the need for) large size and a different speaker principle.."

 

Well , that large size is not exactly typically " because depends on the kind of drivers other than horns and an example are my ADS speakers that yes are " large size " but the size is due that the speakers can goes down to 16hz through two 14" acoustic suspension woofers but today I have the ADS from around 100 hz and up and the soft domes ( silk ) acoustic suspension 2" for the mid-range and 1" for the tweeter ( one a top the other:nearest as it can be. ) needs a very small  " box space " due to its very high gauss magnets ( are not vented and non-ferrofluid. ) around 24k in the tweeters and 18K in the mid range, both drivers made it in Germany for ADS and its efficiency is 95db ( almost a horn . ). Unfortunatelly the drivers manufacturer just does not exist any more.

 

R.

@rauliruegas 

it’s true - I am ATC USA and do not want to hide that.   Previously I’ve worked for EV (their rep out of Chicago including OEM)and JBL (in charge of cinema and installed sound in the USA)and now ATC ( I’m the importer for both pro and hi fi for the entire US).  I have the privilege of being able to ask an engineer who does driver design for living what’s what.  My goal is as much for me as for my customer: the more you know the better, as most bad decisions in audio are made based on bad info or lack of info.  There is a lot of misleading info posted on forums - this is what motivates me to post, to represent a different perspective, to represent what I know to be true.

Brad