by ichabod » Thu Jan 27, 2005 5:39 pm
It's quite refreshing to see all those innards of the LS 3/5a. The LS has gathered enough controversy already (dividing some) over these two versions of the x'overs, the older much revered 15 ohmers vs. the newer 11 ohmers.
There's been a fight which sounds best amongst staunched users specially in Asia, notably Hongkong, raising the value of the 15 up to 3,000 U.S. like the one that CIA owns, the notoriously expensive much sought after "white belly."
As you comb and read the LS group postings, you will find some claims about how good those 15 ohmers are in comparison Yet in the shoot out, the one that bested all other LSs (assorted 15 and 11 ohmers and their manufacturers) ) was an 11 ohmer made by harbeth. Imagine there were no less than 7 of the 11 ohmers I believe out of 11 LSs that were included in the shoot-out that scored well.
I've been reading through Gordon Holt's review again and again where the author has cited some of the differences in sound between the old and newer LSs, and I have listed down some of the comparisons he made on both old and new. I suppose Gordon found it interesting to follow the LS through the years. So here are his comments. Take it with a grain of salt. After all, no one here finds his LS as bad sounding. Neither did the shoot-out results yield a bad LS 3/5a.
On the 15 ohms tizzy tweeter he mentions that the "constant impedance resistive divider has improved the tweeter, making it sweet and less "tizzy" due to kef's improved quality control and research on computer aided production for consistency which has allowed the the impedance from "16" or "15" ohms to go to "11" ohms. Harbeth may have had a hand in this.
He also mentions there that the original LSs (the 15 ohmers that is) had neoprene surround while the latter had PVC formulation to "reduce the amplitude of the persistent peak around 1 kHz." We have learned also later from Derek Hughes of spendor about this peak as a result indeed of the deterioration of the surround which indeed causes the LS (whether 15 or 11) to peak at even lower than 1 kHz as mentioned by Gordon. Derek mentioned something in the region 800 to as high as 1,200 kHz. And this is caused by time, humidity, and other natural elements like pollutants I'm sure.
Sound of the old according to Gordon Holt has slight nasality. Now I have a review of the Harbeth LS 3/5a that confirms this nasality indeed against the Harbeth P3 in comparison.
Just for the record. The article I'm refering to is from "Stereophile" Dec. 1993, Vol. 16 No. 12.
"The Harbeth LS 3/5a features the delicious midrange associated with the design. Voices sounded absolutely natural, with only a slight degree of extra chest tone on spoken male voice to reveal the highish -Q bass alignment. The old pair of Rogers LS 3/5a were revelaed as sounding nasal in comparison with the new pair. In absolute terms, however, there was still a trace of nasality present with the Harbeth version....Surprisingly, considering the fact that both speakers were built to a standard specification,albeit 15 years apart, the Habeths sounded considerably less tizzy in the high treble region than my old Rogers. The ride cymbal in Miles Davis' "So what" from "the Kind of Blue" (SuperBit mapped Sony CK 52861) was still very prominent, but there was more of a feeling that it was a physical instrument made from brass, compared with the 1977 speakers, which emphasized the white-noise aspect of its sound."
The above confirms what I said Holt said above.
To conclude on anything but debate, Gordon goes on to say that the dynamics of the 11 have improved, is less compressed from the originals -- treble less tizzy overall, and when compared to other speakers like the A.E. HE1 and the Celestion SL 600 Si, the LS 3/5a has the least colored midband, throws a deep, beautifully defined soundstage, and a sweeter top than it used to be."
I'm not too sure if these snippets of info from both Gordon Holt and John Atkinson will serve its own purpose, to enlighten us further on what really went on in the development of this classic "cat coffin" for a speaker. After all, all that matters now is its sound.
I've yet to hear a bad sounding LS 3/5a from both sides of the camp if indeed there's truly such a one. Blame those HK guys for raising the cost of the LS 3/5a. You can bet they're the ones who's made a killing on the white belly!