What's your OTL tube amp experience and suggestion?

I found that the Atma-Sphere Amplifiers sound warmer if you change out all the 6SN7 Tubes provided by Ralph.

The one Ralph gives with the amplifier are Chinese made tubes which to me sound a little bright in the upper regions. Once I swapped these out for good pair of NOS tubes everything changed.

The Noise is most likely from the Tube not the Amplifier. I had the same issue with one channel constantly buzzing, These tubes I used in other pre-amps were dead quiet but in Atma-Sphere they seems very noisy. Once i changed them out for other NOS tubes the noise was gone.

The noise is not from the Pre-amp or the amplifier but the Tubes them selfs, Some of these tubes never show signs of noise in my other pre-amps but for some reason they do in Atma-Sphere.

So the goal is to feed these babies good quality low noise tubes. Once you got the tube noise down and the system dialled in with the tonal balance the system can have a nice warm balancing sound.

Just an advise for those who want a warmer sounding OTL on Atma-Sphere. Use some of the RCA, Sylvinia, Ken-rads. The Sophia Electra used on the pre-amp softened up the system too much to my liking.

Sorry mike I misread your post.

Tenor has a bad reputation in Asia. They also gave OTL in general a bad reputation. Most buyers don’t understand their were tons of companies coming out with OTL and only to go out of business as none of them could figure out how to make a Stable OTL Design.

Everytime i speak of OTL to someone, Tenor would come up into the conversation as something that used to blow up like a dynamite!!!

Simple fact is Most OTL on the market are not built Like Atma-Sphere. These companies that try to work on OTL cant seem to figure out a Stable build, Atma did this decades ago.

The Simple answer to OP issues is, If you want OTL Stick to Atma-Sphere and you will have Years of trouble free operation.

Sorry but DartZeel is not on the same league as the Atma-Sphere Amplifiers. The Atma is a lot more transparent, faster and throws a larger sound stage and does not sound like a tube nor a solid state. Should I even mention the Atma not only has better transparency it is a lot more emotional to listen too. It draws you into the music and does not sound mechanical.

DartZeel make good solid state amp but I'm sorry it cant be compared to a Atma-Sphere.

Ozzy, have you experimented with the RCA Output Tubes?

If you want Reliability, Service, Sound Quality, Years of Enjoyment i wholeheartedly recommend Atma-Sphere Gear, Nothing like it.  I have bought and sold amplifiers in my 20 years in this hobby and finally settled with the Atma-Sphere.  This is coming from someone who used Single Ended Designs, Push Pull, Solid States, Hybrids. 

The only issue you will find with these amps is paring with the right speaker it can be challenging at times if your speaker has an unusual load. If you get pass this stage you will experience something in audio which most audiophiles strive for but never reach. Pure Musical Bliss!!!

You should visit John Wolff Of Classic Audio Loudspeakers and see what he has done with this Atma-Sphere paired with the high sensitive speakers.

300B can not produce that much power. Something fishy about those amps.