Tenor 75 OTL vs SET amps

bonzo75

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Did he explain why?

Did he express a preference ordering which includes NAT or Jadis or VTL amplifiers?

He doesn't know about the others
 

KeithR

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I am also quite familiar with the NAF 845 having heard it in a number of configurations and it is a very good amp but does not have the transparency of the Silvaweld...even into high sensitivity speakers. It is also warmer and rounder sounding...preferred by some but to others coloration. I would call it a mild coloration that does not cover over too much but is there nonetheless.

Brad- I was close to buying the NAF a few times. Did you ever compare to the Viva or Mastersound? They seem like the 3 italian SET studs.

I've only owned a PSEP Mastersound which was lovely, though did lack some resolution (it also only retailed for $3k)
 

bonzo75

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Brad- I was close to buying the NAF a few times. Did you ever compare to the Viva or Mastersound? They seem like the 3 italian SET studs.

I've only owned a PSEP Mastersound which was lovely, though did lack some resolution (it also only retailed for $3k)

Talking to the Italians I met on my recent trip, and you can confirm this with Gian60, they prefer the Viva to those. I heard the Viva Solista and Viva Linea on The Alexandria X2S2 and it was excellent. Though both the owner and Gian prefer the CH Precision to the Viva preamp, but that's a different budget, and both use the CH phono. They also rate Viva above the Airtight. The key thing is that Tenor killed the Airtight, like the best no contest in amps I ever heard. That was on Lansche and Magico mini
 

Mike Lavigne

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Talking to the Italians I met on my recent trip, and you can confirm this with Gian60, they prefer the Viva to those. I heard the Viva Solista and Viva Linea on The Alexandria X2S2 and it was excellent. Though both the owner and Gian prefer the CH Precision to the Viva preamp, but that's a different budget, and both use the CH phono. They also rate Viva above the Airtight. The key thing is that Tenor killed the Airtight, like the best no contest in amps I ever heard. That was on Lansche and Magico mini

Tenor 75 watt OTL has the purest sparkling, midrange, with zero tube darkness or soft transients.....and low noise. it just needs a benign speaker impedance, and efficiency, and modest sized room.
 

bonzo75

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Tenor 75 watt OTL has the purest midrange, with zero tube darkness or soft transients. it just needs a benign speaker impedance, and efficiency.

Do you know of anyone who compared it to SETs on a circa 99db speaker? I know that on other speakers Tenor were preferred to SETs as per online forum reports, (except for the Antique Sound Labs which HP put forward).
 

Mike Lavigne

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Do you know of anyone who compared it to SETs on a circa 99db speaker? I know that on other speakers Tenor were preferred to SETs as per online forum reports, (except for the Antique Sound Labs which HP put forward).

back when I owned the 75 watt Tenor OTL's, those using them on 99db efficient speakers used the 15 watt version. the 15 watt version came first, then it was 'hot-rodded' into the 75 watt version.

otherwise I can't really say about the 75 watt version used on 99db speakers.

I do recall that the 15 watt versions had no reputation for exploding.
 

spiritofmusic

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Sounds like they'd be a perfect match for my Zus
101dB/1m eff, 8 Ohms steady load/16 Ohms switchable
 

morricab

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Brad- I was close to buying the NAF a few times. Did you ever compare to the Viva or Mastersound? They seem like the 3 italian SET studs.

I've only owned a PSEP Mastersound which was lovely, though did lack some resolution (it also only retailed for $3k)

I have not heard at any great length Viva or Mastersound. Viva a bit at shows but it was not that impressive, Mastersound not at all.

I have personally found the Eastern European brands to be more neutral and dynamic: KR Audio, NAT, Ayon, Aries Cerat (Cyrpus is not techincally eastern Europe but it is quite close to the middle east) etc. Maybe it has to do with their use of more modern output tube designs?

OTLs are tough to beat in terms of transparency but they are not perfect in other areas, like tonal balance and coherence.
 

bonzo75

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Tone was better than airtight. Are you referring to Tenor 75 specifically or OTLs in general?
 

morricab

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back when I owned the 75 watt Tenor OTL's, those using them on 99db efficient speakers used the 15 watt version. the 15 watt version came first, then it was 'hot-rodded' into the 75 watt version.

otherwise I can't really say about the 75 watt version used on 99db speakers.

I do recall that the 15 watt versions had no reputation for exploding.

Probably a lot kinder on the air conditioning too.

I heard the 75 watter on a pair of Dynavox 3.2, 96db/watt speakers. That was quite good sound...similar to the Silvaweld OTL Tube reference monos I had many years ago...they didn't blow up but they couldn't hold bias very well. Also, 4 x 6C33C per channel was a heat monster. I don't know how anyone lives with big amps from Joule Electra for that reason alone.
 

Diapason

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Also, 4 x 6C33C per channel was a heat monster. I don't know how anyone lives with big amps from Joule Electra for that reason alone.

It's a serious issue alright. When I ran the amps in my avatar (in monoblock form) in my very small nerdcave, summer listening was very unpleasant, and even a couple of hours led to a massive heat differential between the nerdcave and the rest of the house. Air conditioning isn't a thing here, so boxer-short listening was not uncommon.
 

spiritofmusic

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I'm running quad 211s in my NATs from tmrw, luckily have a large room to disperse heat
I enjoy the odd 10 hr stint listening to music thru, always a torture test re temp w the NATs
 

KeithR

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Probably a lot kinder on the air conditioning too.

I heard the 75 watter on a pair of Dynavox 3.2, 96db/watt speakers. That was quite good sound...similar to the Silvaweld OTL Tube reference monos I had many years ago...they didn't blow up but they couldn't hold bias very well. Also, 4 x 6C33C per channel was a heat monster. I don't know how anyone lives with big amps from Joule Electra for that reason alone.

I heard the large Rite of Passage monos a long time ago at CES on Acapella speakers. Must have increased room temp by at least 10 degrees.
 

KeithR

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I have not heard at any great length Viva or Mastersound. Viva a bit at shows but it was not that impressive, Mastersound not at all.

I have personally found the Eastern European brands to be more neutral and dynamic: KR Audio, NAT, Ayon, Aries Cerat (Cyrpus is not techincally eastern Europe but it is quite close to the middle east) etc. Maybe it has to do with their use of more modern output tube designs?

OTLs are tough to beat in terms of transparency but they are not perfect in other areas, like tonal balance and coherence.

Thanks- I wanted a Solista for a long time, but the US distributor promised a demo and never came through. It could be the best looking amplifier of all time? It has a "golden sound" MO, which was always my worry without a demo.

The "hot" new amp is the Linear Tube Audio, David Berning licensed ZOTL design. You might check it out. I believe it has more tone than typical OTLs and uses EL34s.
 

bonzo75

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Thanks- I wanted a Solista for a long time, but the US distributor promised a demo and never came through. It could be the best looking amplifier of all time? It has a "golden sound" MO, which was always my worry without a demo.

The "hot" new amp is the Linear Tube Audio, David Berning licensed ZOTL design. You might check it out. I believe it has more tone than typical OTLs and uses EL34s.

The Solista is a very good amp, and yeah, it looks great. Used prices in EU are good, and like I said, the Italians prefer it to NAF, Mastersound and Airtight.
 

morricab

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I'm running quad 211s in my NATs from tmrw, luckily have a large room to disperse heat
I enjoy the odd 10 hr stint listening to music thru, always a torture test re temp w the NATs

NATs with 2 x 211 per channel get hot, no question about that. My NAT Symbiosis though got at least as hot though. 100 watts of Class A from a Single Ended amp and with the outputs regulated means an additional set of heating elements. That is why my Symbiosis had four big vertically mounted heat sinks (my wife and I called it the BatterSea power station). The two in the back were for the single output transistor per channel (it was mounted on the bottom of the heat sink). The two in the front had identically mounted transistors that were acting as regulators for the output transistors and so generated just as much heat.

The Silvawelds with 4 x 6C33C per mono were on another level from that. I have never encountered another tube that gets as ferrociously hot as the 6C33C. It is amazing really, especially given that it is not so huge. I think it is because of the huge current draw for the heaters. I used to have trouble turning them on without tripping the circuit breaker (no soft start apparently). The Silvawelds were over 500 watts per monoblock in terms of power consumption...think of that...over 1000 watts of space heater.

Even the little Wall Opus M50s were serious heaters with 2 x 6C33C per monoblock...not as bad as the NAT Symbiosis but about 600 watts for the pair in terms of power consumption. NAT Symbiosis consumed around 800 watts continuously.

NAT Se2Se are probably around 300 watt per mono I would guess.
 

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