Not at 90dB. I had a shorter model of this driver and 90dB is no problem
Ron’s New System
- Thread starter Ron Resnick
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Totally different drivers and this one is only operating from 200hz or so and up. No bass makes a big difference
So?? Different speaker different amp…no connection. I owned Apogee Caliper signatures for many years, even drove them a bit with Cary CAD-572se monos (20 watts) just fine…didn’t have an amp die on them even once. They were harder to drive than Duettas because they were 3ohm for the most part. The BG driver is a flat 4 ohms and 89dB…not really challenging.
Ok, but if it shuts in triode mode and not in pentode mode, it was not just a difference in loudness. In tridoe it was still 180 watts. So it is losing drive for sure. I know you preferred NATs on Apogees as well which were 6 ohm, and I heard them underdriven. So, I am not surprised Phil heard clipping with the VTL in triode mode.
Drove my DIY Hybrid that used a BG driver and a 10 inch woofer in a sealed box. Active crossover at 300hz (Accuphase F25). Ran it with a pair of KR VA350i 30 watt SETs. Played cleanly quite loud…ask Christoph…he liked them a lot.
The 75 inchers are nominally 6 ohms (longer than the 50 inch, more impedance), even easier.
Could be some kind of amp protection mode on the Ayon…they are quite Sophisticated amps that way. For sure it wasn’t the load or the power. You shoukd be surprised because to hit 90dB at Ron’s listening position would take less than 10 watts. Do the math…and remember that a line source drops off at half the rate of a point source. With my Acoustats I measured only about 1dB drop from in front of the speakers to my 3 meter listening distance…now my room was not very big so a larger room will experience a bit more.
We can ask Ron to measure SPL at just in front and at the listening position and see what the drop with distance is.
i am stating the fact that the triode mode worked differently to the pentode mode in drive. I have also heard NAT transmitters on 6 ohm apogee, they don’t work well on the highs either, not just bass.
Except apogees are low efficiency speakers, his Pendragons are moderate and the NATs aren’t push pull so outside 8ohm impedance should be difficult.
VTL was built for inefficient speakers let’s be honest. They even spec their amps into 5ohms. JA measured triode mode clipping at 315 watts into 4 ohms. He actually said triode mode worked best into low impedances so if the ribbon actually is a stable 6-8 ohms tetrode could be better non intuitively. Indeed 8 ohms shows flatter distortion curve in tetrode which for triode increases more substantially in the highs.
No, what you heard was crappy Apogee active crossover making not nice highs. Honestly you are really out of your depth here and talking a lot of nonsense.
Also, you are trying to compare a different brand of amp, that is designed differently on a different speaker…how can we take that seriously? Do you know somehow that the Ayon Orthos and VTL are the same design?? Now you throw NAT Transmitter into the mix on again another speaker.
You probably never heard the Grands when they were running off a Diva passive crossover full range without the subs. We compared the CAT JL2 signature to the NAT SE2SE monos. The NATs were better and sounded very authoritative on the panels…no problem with bass or highs and plenty of headroom.
20 watts on 84dB sensitivity speakers? I am going to call "no way, Jose!" on that one!
I tried a 24 watt LM219ia on my 86db very easy 6ohm Maggie 20.7s… nice when there was just a girl and a guitar but other than that Jose also wasn’t having a bar of it. The essential drive was missing in action… as lovely as certain moments were. Same SET amp on the Devore 0/96 upstairs was rocking the room with plenty of verve. But a hell amp to carry up stairs though
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Flat impedance on 4 ohm tap gives probably 10 usable watts. 84 dB for 1 watt, 87 for 2, 90 for 4 watts, 93dB for 8. Probably could just about hit 95dB. Keep in mind this was in a 20 sqm room. That is for just one speaker. Now add at least 3dB for a pair of speakers and a drop off of 2-3dB for the listening distance. For normal listening no problem. Sounded a bit loose in the bass (Cary transformers were a bit undersized) but otherwise just fine. Was it better than my Sphinx Project 14 mkiii that made 360 watts into 4 ohms? No but it wasn’t nearly as far behind as you might think.
Maggies always needed more juice to “wake up” than Apogees. My friends and I learned this through many pairs ( I never owned them…they did). 1.5qr, 1.6qr, 2.5r, 3.6r…etc. Apogee sounds more alive below 85dB.I tried a 24 watt LM219ia on my 86db very easy 6ohm Maggie 20.7s… nice when there was just a girl and a guitar but other than that Jose also wasn’t having a bar of it. The essential drive was missing in action… as lovely as certain moments were. Same SET amp on the Devore 0/96 upstairs was rocking the room with plenty of verve. But a hell amp to carry up stairs though
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