A new amp in the mix. From tube to solid state
- Thread starter prem
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Hi denom
I am pretty confident it will be better on most counts. The only place where i have a little doubt is in the mids. It might sound a little thin. In which case i will have to look at a tube pre with minimal gain
I am pretty confident it will be better on most counts. The only place where i have a little doubt is in the mids. It might sound a little thin. In which case i will have to look at a tube pre with minimal gain
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Prem congrats!!
Last time you mentioned about first watt ,I thought you are joking!! again I am sure about ur research ,so very keen on hearing the upcoming combo...great!!
Last time you mentioned about first watt ,I thought you are joking!! again I am sure about ur research ,so very keen on hearing the upcoming combo...great!!
Prem,
Congrats on the new buys. The SIT is a bespoke transistor commissioned by Mr Pass and is supposed to be a combo of the best of tube and solid state.
PS: what is it with both Sadhanaa owners in Mumbai changing amps?
Congrats on the new buys. The SIT is a bespoke transistor commissioned by Mr Pass and is supposed to be a combo of the best of tube and solid state.
PS: what is it with both Sadhanaa owners in Mumbai changing amps?
Prem,
Congrats. SIT2 is a terrific choice. I am a super big fan of Pass designs. If you have not heard the Pass amps before, you would be in for a big surprise on the level of detail these can put out. Pass's signature is clearly audible in his designs. The SITs are special to Pass Labs and are custom made to his specs and requirements. There is hope that these output devices will be available for DIYers from the man himself.
Though I have not heard the Rethms, the Lowther drivers are known to be big midrange performers. Will be keen to hear your experience with the combination.
Cheers.
Congrats. SIT2 is a terrific choice. I am a super big fan of Pass designs. If you have not heard the Pass amps before, you would be in for a big surprise on the level of detail these can put out. Pass's signature is clearly audible in his designs. The SITs are special to Pass Labs and are custom made to his specs and requirements. There is hope that these output devices will be available for DIYers from the man himself.
Though I have not heard the Rethms, the Lowther drivers are known to be big midrange performers. Will be keen to hear your experience with the combination.
Cheers.
Thanks Anilva. I too am looking forward to hearing the SIT 2. Also great to hear SIT may be made available for DIYs. I was not aware of that
jls 001, one is moving out of Gaanam, the other is getting one. Its not very easy to mate an amp with the Saadhanas. The Gaanam works wonderfully with the Rethms and is the most obvious choice. I hope the SIT 2 does too.
jls 001, one is moving out of Gaanam, the other is getting one. Its not very easy to mate an amp with the Saadhanas. The Gaanam works wonderfully with the Rethms and is the most obvious choice. I hope the SIT 2 does too.
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Interesting. Some time back, I was also looking at Pass Labs and FirstWatt SIT, wondering about an upgrade of my Ayre amp which has been my reference for solid state. Here is what Charles Hansen of Ayre wrote about SIT:
Quote: SIT = Static Induction Transistor
This is another name for V-FET, or Vertical Field Effect Transistor which is a power J-FET or Junction Field Effect Transistor. A JFET is normally a small-signal device that is used in preamps or the input stages of a power amp.
FETs in general have advantages over traditional Bipolar Junction Transistors (BJTs), which is just a fancy name for a regular transistor. The VFET was the first power FET, and was used briefly in a couple of amplifiers from Sony and Yamaha in the '70s. Those amps were highly regarded at the time, especially the Yamahas (B-1 and B-2, do a Google search). However, biasing them was rather difficult, they were expensive, and quite rare and difficult to purchase.
Shortly after those transistors were developed, Hitachi developed the power MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The metal oxide provides an insulating layer between the input and output, and these devices had a lateral structure. These transistors were relatively inexpensive, easy to procure, and super easy to bias. They became an immediate hit in the audio world, as typified by the Hafler amps, as well as many others. The VFETs faded from the scene shortly thereafter.
After a few years, the American manufacturers focused on MOSFETs for switching applications. These have a vertical structure, but don't confuse a V-MOSFET with a VFET. Most current audio amplifiers that have MOSFETs use these V-MOSFETs, but in my experience they don't sound as good as the L-MOSFETs as developed by Hitachi.
Back to your original question regarding SITs (VFETs), they could have some advantages over other types of transistors for audio. But its hard to say for sure as all of the data sheets are in Japanese. They are designed for RF use and only available in one polarity, so that rules out complementary circuits, which are almost universally used these days. They are also expensive and not distributed in the US.
Nelson Pass currently offers a First Watt amplifier that uses a low-voltage power JFET design (not an SIT). For a while the Japanese Toshiba website had a presentation that claimed they would make SITs using SiC (Silicon Carbide, offering higher voltage capabilities than normal silicon devices), but that has disappeared.
All-in-all, I would say nothing to get your skirt blown up. A much better new technology (in my opinion) is the ThermalTrak devices offered by On Semiconductor. We are using them in our new amp, Audio Research just announced a hybrid amp with them, and I am told that both McIntosh and Crown (pro audio) are developing new products with them.
Unquote: I was wavering between Audio Research and Aesthetix hybrid amps and finally went for the latter. After listening to it, I am now sure it was the right decision. The owner of Aesthetix has acknowledged that Charles had helped him greatly in the design of the amp, similar to the way they (along with David Reich who is associated with Classe too) were associated long back in Theta in the development of the great Dreadnaught amplifier.
I hope you have a good experience in the world of solid state.
cheers.
murali
Quote: SIT = Static Induction Transistor
This is another name for V-FET, or Vertical Field Effect Transistor which is a power J-FET or Junction Field Effect Transistor. A JFET is normally a small-signal device that is used in preamps or the input stages of a power amp.
FETs in general have advantages over traditional Bipolar Junction Transistors (BJTs), which is just a fancy name for a regular transistor. The VFET was the first power FET, and was used briefly in a couple of amplifiers from Sony and Yamaha in the '70s. Those amps were highly regarded at the time, especially the Yamahas (B-1 and B-2, do a Google search). However, biasing them was rather difficult, they were expensive, and quite rare and difficult to purchase.
Shortly after those transistors were developed, Hitachi developed the power MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The metal oxide provides an insulating layer between the input and output, and these devices had a lateral structure. These transistors were relatively inexpensive, easy to procure, and super easy to bias. They became an immediate hit in the audio world, as typified by the Hafler amps, as well as many others. The VFETs faded from the scene shortly thereafter.
After a few years, the American manufacturers focused on MOSFETs for switching applications. These have a vertical structure, but don't confuse a V-MOSFET with a VFET. Most current audio amplifiers that have MOSFETs use these V-MOSFETs, but in my experience they don't sound as good as the L-MOSFETs as developed by Hitachi.
Back to your original question regarding SITs (VFETs), they could have some advantages over other types of transistors for audio. But its hard to say for sure as all of the data sheets are in Japanese. They are designed for RF use and only available in one polarity, so that rules out complementary circuits, which are almost universally used these days. They are also expensive and not distributed in the US.
Nelson Pass currently offers a First Watt amplifier that uses a low-voltage power JFET design (not an SIT). For a while the Japanese Toshiba website had a presentation that claimed they would make SITs using SiC (Silicon Carbide, offering higher voltage capabilities than normal silicon devices), but that has disappeared.
All-in-all, I would say nothing to get your skirt blown up. A much better new technology (in my opinion) is the ThermalTrak devices offered by On Semiconductor. We are using them in our new amp, Audio Research just announced a hybrid amp with them, and I am told that both McIntosh and Crown (pro audio) are developing new products with them.
Unquote: I was wavering between Audio Research and Aesthetix hybrid amps and finally went for the latter. After listening to it, I am now sure it was the right decision. The owner of Aesthetix has acknowledged that Charles had helped him greatly in the design of the amp, similar to the way they (along with David Reich who is associated with Classe too) were associated long back in Theta in the development of the great Dreadnaught amplifier.
I hope you have a good experience in the world of solid state.
cheers.
murali
Congrats, Prem! I had the opportunity to listen to a pair of the older Rethms recently with their own tube amps (older protos) and I was completely smitten. To get them to make music in an even better way would be something truly great to experience!
Good. So it will be 200W continuous power consumption to generate 10W output. I don't know about your speakers but presume they are of "high efficiency".
By the way, I have a good friend who has always been a fan of Pass designed amplifiers. He had used quite a few of the Pass Labs stuff. When asked about his hesitation on going to First Watt, his main concern was the "loss of dynamics". So he continues with other solid state and tube amps, driving his relatively inefficient (like my Vandys) Thiel speakers, and happy with them.
Let me hope you get what you are really looking for and don't miss the others relative to your present setup.
Bye and cheers.
murali
By the way, I have a good friend who has always been a fan of Pass designed amplifiers. He had used quite a few of the Pass Labs stuff. When asked about his hesitation on going to First Watt, his main concern was the "loss of dynamics". So he continues with other solid state and tube amps, driving his relatively inefficient (like my Vandys) Thiel speakers, and happy with them.
Let me hope you get what you are really looking for and don't miss the others relative to your present setup.
Bye and cheers.
murali
Prem I have been tracking an almost identical path as you have! I read Srajan's Firstwatt and Saadhana reviews on 6moons and then later wrote to Jacob George. Jacob has invited me to an audition in Cochin which I am looking forward to when I get the time. Still quite a ways from pulling the trigger but its great to see someone else on the same journey.
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Purchase the Audiolab 6000A Integrated Amplifier at a special offer price.
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