System that sounds so real it is easy to mistaken it is not live
My current stereo system consists of Oracle turntable with SME IV tonearm, Dynavector XV cartridge feeding Manley Steelhead and two Snappers monoblocks running 15" Tannoy Super Gold Monitors. Half of vinyl records are 45 RMP and were purchased new from Blue Note, AP, MoFI, IMPEX and some others. While some records play better than others none of them make my system sound as good as a live band I happened to see yesterday right on a street. The musicians played at the front of outdoor restaurant. There was a bass guitar, a drummer, a keyboard and a singer. The electric bass guitar was connected to some portable floor speaker and drums were not amplified. The sound of this live music, the sharpness and punch of it, the sound of real drums, the cymbals, the deepness, thunder-like sound of bass guitar coming from probably $500 dollars speaker was simply mind blowing. There is a lot of audiophile gear out there. Some sound better than others. Have you ever listened to a stereo system that produced a sound that would make you believe it was a real live music or live band performance at front of you?
Dear @jetter : Good to know you own Mweitner designs, he was and is a very well regarded designer/manufacturer and I think that almost any audiophile read or knows some body that speaks about EMM Labs CD many years ago. As a company Meitner still exist and doing fine. Here some information of Meitner:
https://www.emmlabs.com/legacy.php
R. |
Mijo, You wrote, with reference to our SL speakers: "I went back to Sowter and they will make custom transformers. I drove the Acoustats with 100:1 transformers from 125 Hz up and it worked well. Right now I am crossing out of the stats at 100 Hz. I also am thinking about getting RAAL ribbon tweeters too cover 12 kHz up. I wonder if the bass transformer would handle that range or should I have 100 or 150:1 transformers made. The Plitron is too small." My questions are with reference to your last two sentences. What range are you talking about that you wonder whether the bass transformer could handle it? If you are thinking about, say, 100Hz to 12kHz, I would say no. One reason for my opinion is that when I measured the OEM bass transformer, it rolls itself off at or around 2kHz, probably due to self-inductance. Another reason is that you need to keep in mind the effect of the ESL step-up on impedance seen by the amplifier is the converse of using a SUT with a phono cartridge. The impedance seen by the driving amplifier is the intrinsic Z of the screen with no transformer divided by the square of the turns ratio. So as you go up in frequency, a 1:250 turns ratio is going to result in a very low impedance for the amplifier, except as the self-inductance of the transformer seemed to dominate when I measured Z with the bass transformer alone driving the speaker. Anyway, I would not be hopeful that this is a good idea. And what makes you say the Plitron audio transformer is too "small"? Have you ever seen the audio step-up transformers used by Martin-Logan and some other companies? They ARE tiny, but SL use substantial transformers, and the Plitron 1:75 full range step up appears to be about the size, at least, of the OEM SL toroidal transformer they use for treble. Or is it the turns ratio (1:75) that you think is too small? To that I would only say that 1:90 of my Australian sourced transformer is excellent. 1:75 in terms of voltage is not that different, and because of the effect of the turns ratio on impedance (see above), Z at higher frequencies will be a bit higher than what I observe with a 1:90 ratio. So it might be a trade-off with no untoward effects on perceived efficiency. Anyone, like Intact Audio, who actually knows transformers is welcome to correct me on these generalizations. |
@rauliruegas , at $85K a pair I would hope so, but from a cost/performance ratio I will take the JC1+ any day. Is Meitner any better than John Curl? I do not know the answer to that question. At this point due to the reputation of the Atma-Sphere MA 2s driving my speakers. I am spending 1/2 that amount on them. We shall see how that works out. The JC 1s will be shifted to subwoofer duty. @lewm , The Plitrons will not handle the power I plan on dishing out. I can have a pair of 100:1 Sowters made that will and I should think would do a dandy job of driving the SLs from 100 Hz to 12 kHz. |
What do you mean by "power"? I get that you want to play at high SPLs, but if you are going to use bass and high treble supplementation and probably roll off the response of the SL speakers with very steep slopes, given your penchant for digital crossovers, then why do you anticipate needing the transformer to take lots of power? Have you evaluated the specifications of the Plitron toroid, so as to form a basis for your belief they cannot be driven hard, or what? Anyway, I have no compulsion to dissuade you from your aim to use Sowter transformers. (1:100 would be technically more correct than 100:1, BTW.) Sowter certainly is well regarded, although I did not associate them with making audio step-up transformers to drive ESLs. Sure, go for it. My recommendation of Plitron was solely based on the idea of your driving the speaker with two transformers (one for bass and the other full range) and dumping the RC network in the process. However since you are venturing into the unknown, you might want to find a way to experiment with using a single 1:100 step-up before investing in a custom build of two of them. (Acoustats are not identical to SLs in terms of stator to diaphragm spacing and bias voltage, although using separate bass and treble transformers was originally the idea of Acoustat, borrowed by SL in the late 90s or so.) |
