I owned the Tenor 75 watt OTL's for 3 years (2001-2004).....on Kharma Exquisite 1D's.
it's going to be more linear than any SET I have heard. and will have more power with than many SET's if you find the right speaker but......there are a few things to consider. the early Tenor OTL's (the one's I owned) would grenade easily. mine did ignite a couple of times and took out ceramic mid range drivers on my Kharma's. after 2005 there were new owners of Tenor and they re-worked the circuit and it is more stable. so make sure you get an example that is newer spec. then get a relatively efficient speaker with an easy and flat impedance curve. lastly they get really hot. so prepare to deal with lots of heat.
it's one of my all time favorite tube amps, but needs considerable care in speaker matching.
Nothing like living on the edge .... were there reports of other amps of such vintage having similar flare ups?
.and that match was a very sexy sound. so many followed my discovery and put together various Kharma speakers with Tenor OTL's. then these beautiful amps revealed their nasty nature and so I was not the only one who had issues. then Tenor designed their 300 watt Hybrid mono blocks......which turned out to be worse yet. that adventure bankrupted Tenor and it was not a pretty picture.
a few of us got stuck holding the bag on those amps.....then the assets of Tenor were bought and the company was re-formed and they cleaned up the engineering and re-launched the products and they have been solid since.
there are exceptions; the Atma-sphere OTL's seem to be quite stable.
btw; my personal sonic compass/reference is rooted in my memory of the Tenor OTL and then how the darTZeel captured and built upon what I liked about the Tenor OTL. so this subject is near to my heart.
Hello Mike, allow me to add that the reason why Tenor at the time, this is over 10 years ago, went bankrupt was a direct consequence of wanting to go the last mile in customer service. Effectively, by attending their customers by repairing the broken units free of charge and a whole product recall action associated to that, stretched the funds so much they needed a new capital injection which was done by Jim Fairhead, still current owner and CEO.
As you write, the 'new' Tenor amps (again existing for 10 years since the above happened) work flawlessly and Tenor Audio Ltd. has shown to be very responsive to any customer feedback since I am serving as an audition centre for them in Europe.
Regarding the OTL, I have tested both the 350M and 175S power amps with my Rockport Avior speakers and they do both flawlessly, although the Avior has anything but a flat impedance curve! My previous Lamm 1.2 Reference were struggling a lot more in comparison. Of course the current models are only OTL on the input stage and solid state on output stage, making them effectively a hybrid design, but successfully so I dare to say.
The true OTL is not made anymore by Tenor although they still do have some units on their shelves that have been fully upgraded to do away with their flaws. So, if anyone is interested in the SOTA for OTL, they can still investigate the Tenor option in all safety! Please PM me if you want any further information.
Now, as I also normally have the Aries Cerat Concero 65 true SET amps, I can compare the current Tenor models with the Aries and then we enter another world. In brief, if you need a lot of power because you have a really big room or very very demanding speakers, Tenor is the way to go, in all other instances I would choose for Aries Cerat Concero. Worthwhile mentioning that even my Rockports are easily driven by the Conceros as their massive current reserve handle the impedance and phase swings very solidly, in combination with a true SET sound.
Best,
So what about Aries OTL vs Aries SET?
(2) how does the Aries Cerat OTL compare to the Tenor 75 watt OTL in performance? (I'm guessing that the price delta is considerable).
Well the big issue with making such a comparison is the nature of OTL is highly restrictive in terms of speaker options to use case. If you can get similar performance without going OTL why go OTL?
But should a comparison happen I don't imagine that it would be fair giving the Aries Cerat design is the first Single Ended OTL design and also has no feedback. But given the diminutive 20W of power at idle it pulls 1200W from the wall. Another potential deal breaker for many as that amount of heat in the summertime would be quite the challenge.
I was very tempted to introduce this design to the US market, but given the challenges in speaker options, power consumption, etc it will remain a mystery.....
Just FYI, transcendent sound introduced a SET OTL before Aries but it had 1.5 watts on a good day . They now have SET OTL monos with 12 watts.
Hello Mike, allow me to add that the reason why Tenor at the time, this is over 10 years ago, went bankrupt was a direct consequence of wanting to go the last mile in customer service. Effectively, by attending their customers by repairing the broken units free of charge and a whole product recall action associated to that, stretched the funds so much they needed a new capital injection which was done by Jim Fairhead, still current owner and CEO.
Then we'll just say first no feedback SE OTL
Go with the Berning 211/845!!
OTL, SE, plenty of power and reliable.
Berning is not a SE OTL design. It is a 60W PP OTL design
A very good amplifier though I agree
I got an interesting feedback from someone who own the KR VT-6000, Silvaweld OTL 100 Reference, and New Audio Frontiers 845.
For speakers below 90db, he preferred the Silvaweld-KR-NAF.
For speakers over 99 db, he preferred NAF-Silvaweld-KR
I got an interesting feedback from someone who own the KR VT-6000, Silvaweld OTL 100 Reference, and New Audio Frontiers 845.
For speakers below 90db, he preferred the Silvaweld-KR-NAF.
For speakers over 99 db, he preferred NAF-Silvaweld-KR
Steve Williams Site Founder | Site Owner | Administrator | Ron Resnick Site Co-Owner | Administrator | Julian (The Fixer) Website Build | Marketing Managersing |