Aestheix Calypso owners,tube advise needed

I have Telefunken 12AX7s in mine and have played with a variety of new production and old stock 6DJ8/6922s, currently using Mullard 6922s. Enjoy your Calypso. It's a wonderful linestage. Dave

Hi Gandme,

Changing the 12AX7 tube will have a dramatic affect on the sound compared to changing the 6922 tube. As the 12AX7 is in the gain stage of the preamp. All of the recommendations above are excellent. You just need to know what kind of sound you are looking for. You also can change the gain of the preamp by -12db. The Calypso has a 29db gain for the balanced output, that is why you need an exceptionally quiet 12AX7 tube. By lowering the gain to a more realistic 17db a lot of other tubes can be used in this preamp, and the preamp still has plenty of gain for most amplifiers. I have used 1950's Mullard long plates, 1960's Mullard & Telefunken 1960's smooth plates in the 12AX7 positions along with 1950's 5751 GE tubes. They all sound slightly different, with the Mullards & GE having a richer sound in the midrange and the Telefunken being neutral. You will just have to get some different tubes and give them a try as all set ups are different.

Unless you need the high gain, I would suggest you lower the gain in the preamp first as it will reduce the tube hiss thru the speakers substantially. Thats not to say you cannot get a low noise tube to work with the high gain, as I have done so with the Telefunken & Mullard tubes, but it does take an exceptionally low noise tube to do so. All of the dealers above can supply matched tubes, but the tubes you will need with the high gain needs to be matched and low noise, which they can supply but it takes a little work.

Gandme,

A common theme in all of the threads on the Calypso has to do with the Calypso getting a bad wrap of being hard on tubes, because with the wrong tube the linestage can sound noisy (tube hiss thru the speakers). This has to do with the Calypso having such a high gain compaired to most other preamplifiers. Typically you will see the gain of a preamplifier to be between 12 to 18 db, compaired to 29 for the Calypso. I have had the Calypso over 3 years and have found it not to be hard on the tubes, in fact the tube have lasted a long time. You just need the low noise tubes in the 12AX7 position or lower the gain or both.

Enjoy

2nd what Samhar said about buying NOS, and the mentions about low noise tubes. Kevin at Upscale is very stringent in his testing procedures, and his noise grading is spot-on. You are assured of getting exactly what is stated/promised from him, in addition to excellent guidance in finding the tubes to sate your aural palate.

I have a Rhea and Calypso. I can attest that tubes that would otherwise be too noisy or microphonic can often be quelled with Herbies dampers (but you do have to experiment sometimes to get the damper positioned correctly). You should always have at least a pair of these around. They have saved me megabucks and hassles.

The Calypso 12ax7's don't have to be as quiet as those in the Rhea. I use my Rhea rejects in the Calypso. I'm not sure which Calypso gain setting I'm using but I do remember having to change it when I first received the Rhea. The two didn't interact well with the high gain I had selected for the Rhea.

If I recall correctly I was told by Glenn at Aesthetix that if you select an input on your Calypso that is not connected, turn the volume from zero to eight and listen at each increment in between, you will hear the maximum amount of tube noise that the Calypso will contribute to your overall sound. You may only have to listen at eight.

I have not tried old stock American tubes but have tried most of the Euro's including the 10M. I prefer Philips - D getters (Heerlen, Blackburn) and the Hamburg long plate slanted O getter - in the critical gain positions in both the Rhea and Calypso. You might prefer the sound of a Telefunken or even a 5751. It really depends on so many things, your amps, speakers, listening room, etc. The only way to know for certain is to try different types.