@lewm That is correct, the impedance of the bass transformer is quite high, but that is after that fact. I am talking about driving the Vanderveen transformers almost full range except under 100 Hz. All the stock transformers are either blown or in the trash. The Vanderveens measured DC resistance is 0.3 ohms. The MA2s prefer by at least 6 dB driving the Vanderveens with the added resistors. They do not require them, but they do prefer them. Most transistor amps will detonate without the resistors. The Bricasti amps will just continually shut themselves off. The only cross over I am using now Lew is the one at 100 Hz for the subwoofers. With the subwoofers the Vanderveens have no problem driving the SLs full range. It is a beautiful thing.
The Shure V15 V with a Jico SAS/B stylus VS The Soundsmith Hyperion MR and Lyra Atlas SL
On a sentimental lark I purchased two Shure V15 V bodies and one SAS/B stylus. I was always a realistic about the Shure's potential. Was comparing it to $10k+ cartridges fair? Absolutely. The Shure was considered to be one of the best cartridges of the day. Why not compare it to a few of the best we have today?
The Shure has always been considered to be unfailingly neutral. Famous recording engineers have said it sounded most like their master tapes. I do not have an original stylus for the Shure and I can not say that the Jico performs as well.
My initial evaluation was quite positive. It worked wonderfully well in the Shroder CB. With a light mounting plate and small counterbalance weight a resonance point of 8 hz was easily achieved. There was nothing blatantly wrong with the sound. There was no mistracking at 1.2 grams. You can see pictures of all these styluses here https://imgur.com/gallery/stylus-photomicrographs-51n5VF9
After listening to a bunch of favorite evaluation records my impression was that the Shure sounded on the thin side, lacking in the utmost dynamic impact with just a touch of harshness. I listened to the Shure only for four weeks as my MC phono stage had taken a trip back to the factory. I was using the MM phono stage in the DEQX Pre 8, designed by Dynavector. I have used it with a step up transformer and know it performs well. I got my MC stage back last week and cycled through my other cartridges then back to the Shure. The Soundsmith and Lyra are much more alike than different. I could easily not be able to tell which one was playing. The Lyra is the slightest touch darker. The Shure is a great value....for $480 in today's money, but it can not hold a candle to the other cartridges. They are more dynamic, smoother and quieter. They are more like my high resolution digital files. Whether or not they are $10,000 better is a personal issue. Did the DEQX's phono stage contribute to this lopsided result? Only to a small degree if any. I do have two Shure bodies and they both sound exactly the same. The Shure may have done better with a stock stylus. I do not think the age of the bodies contributes to this result at all.
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Dear @lewm : These subs can help you:
SB16-Ultra Subwoofer | SVS (svsound.com)
and I think that you can build the high pass at the input of your amps with one capacitor but I don't know your amps input circuit.
R. |
A Subjective Assessment is found in the Link, of the 'NOS' Sonus Blue, being used on a couple of different drive TT's using the same TA. https://www.audioasylum.com/reviews/Phono-Cartridge/Sonic-Research/Sonus-Blue/vinyl/108/1086507.html
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The DC resistance of an audio transformer means little to nothing with regard to the load (impedance) seen by a driver amplifier. You probably measured R across the primary windings which is always very low, like less than one ohm. What counts for the amplifier is the reflected impedance of the speaker under AC conditions. For example I measured 50 ohms at 100Hz for my SLs. If the turns ratio of the transformer is 1:100, you can treat that info exactly as you would treat the interaction of a cartridge with a SUT. IOW the impedance of an ESL panel per se is very high at such a low frequency because it’s a giant capacitor, as you know. Your MA2s are not having to drive an 0.3 ohm load. |
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