I am new to the FW stuff, but it seems all I read about them is “after 30years of trying different amps, I’ve never heard one like this”. I really love the idea of a triode tube sound without all the expense and maintenance. My speakers are very large horns and 113db sensitive. So I will not require a large watt amp.
From my reading it seems like the SIT transistors are impossible to find. At this current date is there a possibility to make this a reality? Would I be better off building a pair of monoblocks with a different topology? My room dictates that I must have monoblocks due to how I designed and wired it. I have enclosures in the front of the room with xlr inputs and speaker wire wall plate outlets that run to behind my mains. Be easy on a newbie please. Currently using a vta70 tube amp I built. I found bob’s instructions to be very straightforward and hope to find as much ease in the ss world.
From my reading it seems like the SIT transistors are impossible to find. At this current date is there a possibility to make this a reality? Would I be better off building a pair of monoblocks with a different topology? My room dictates that I must have monoblocks due to how I designed and wired it. I have enclosures in the front of the room with xlr inputs and speaker wire wall plate outlets that run to behind my mains. Be easy on a newbie please. Currently using a vta70 tube amp I built. I found bob’s instructions to be very straightforward and hope to find as much ease in the ss world.
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Nice setup!
I can think of a few possibilities:
1) SissySIT:
SissySIT
Zen Mod has a kit available (minus the SIT and input transformer).
The Tokin SIT is still available, for example, from user Pras1170
2) L'amp:
L'Amp: A simple SIT Amp
You should be able to build one using the Tokin or other still available parts like
the 2sk180. The are three variations depending on the loading (with light bulbs,
inductor, or constant current source)
3) Watch for the release of the next Sony Vfet-based project from Mr. Pass.
That should be in the coming months. The expectation is there will be kits
including vfets available.
Hope this helps.
Dennis
I can think of a few possibilities:
1) SissySIT:
SissySIT
Zen Mod has a kit available (minus the SIT and input transformer).
The Tokin SIT is still available, for example, from user Pras1170
2) L'amp:
L'Amp: A simple SIT Amp
You should be able to build one using the Tokin or other still available parts like
the 2sk180. The are three variations depending on the loading (with light bulbs,
inductor, or constant current source)
3) Watch for the release of the next Sony Vfet-based project from Mr. Pass.
That should be in the coming months. The expectation is there will be kits
including vfets available.
Hope this helps.
Dennis
I really like your setup!!
One thing I want to stress : do not expect exact mimic of tube sound with (any) SIT amplifier; even if you make it in same topology as tube one - using high voltages and output xformer , it still wont be carbon copy tube sound ....... nor it can be "tube" amp sans replacing da toobz every other year
if you didn't hear one , you need to read between the lines of all writings in magazines and on the web
I'm augmenting it , of course , good amp is good , from whatever it is made ; what I want to say is that you can have equally good amp made with SITs as made with tubes , with same organic quality of sound , most probably with some virtues even on higher level (easily gotten extremes of frequency band) ....... but you must suppress expectations of having exactly same thing
they are (good one) on same quality level , but never the same
on the other hand , I never heard exactly same two tube amps , even counting on fact that I'm old , lazy and my ears had mishaps with elephants ......
again - I really like that picture ..... even if I have no space for proper horns , I'm always happy to see that someone has
One thing I want to stress : do not expect exact mimic of tube sound with (any) SIT amplifier; even if you make it in same topology as tube one - using high voltages and output xformer , it still wont be carbon copy tube sound ....... nor it can be "tube" amp sans replacing da toobz every other year
if you didn't hear one , you need to read between the lines of all writings in magazines and on the web
I'm augmenting it , of course , good amp is good , from whatever it is made ; what I want to say is that you can have equally good amp made with SITs as made with tubes , with same organic quality of sound , most probably with some virtues even on higher level (easily gotten extremes of frequency band) ....... but you must suppress expectations of having exactly same thing
they are (good one) on same quality level , but never the same
on the other hand , I never heard exactly same two tube amps , even counting on fact that I'm old , lazy and my ears had mishaps with elephants ......
again - I really like that picture ..... even if I have no space for proper horns , I'm always happy to see that someone has
M2x would be a good choice because it is very simple and sounds very good with compression drivers. My SissySIT is on order..... I’m sure both will give you a smile. As far as tubes go I’ve never really had the motivation to jump down the worm hole. It’s expensive to do 45’s. Preamps are much more reasonable and diverse.
Enjoy the journey!
Enjoy the journey!
Thank you for the compliments. My room isn’t as large as I’d like it to be, but due to the constant dispersion horn design, it controls the sound very well.
I was hoping a couple of these chassis would work due to my enclosures only being 15” wide.
Mini Dissipante 3U – diyAudio Store
I also designed each enclosure to have a high flow bathroom fan that exhausts to the outside. They are very quiet at .5 sone and are not audible. So that will help remove the heat from whatever I end up with.
Ultimately I’m looking for the best fidelity I can achieve within a reasonable budget. Also the lower the noise floor is, the better. The high sensitivity is a bit of a curse as well in that regard.
How does a guy get signed up to get on the waiting list or buy these? Is there pricing available yet?
I was hoping a couple of these chassis would work due to my enclosures only being 15” wide.
Mini Dissipante 3U – diyAudio Store
I also designed each enclosure to have a high flow bathroom fan that exhausts to the outside. They are very quiet at .5 sone and are not audible. So that will help remove the heat from whatever I end up with.
Ultimately I’m looking for the best fidelity I can achieve within a reasonable budget. Also the lower the noise floor is, the better. The high sensitivity is a bit of a curse as well in that regard.
And we do have the last round of DIY Sony VFETs coming up.
How does a guy get signed up to get on the waiting list or buy these? Is there pricing available yet?
I plan to use the same bracket size as in the DIY Sony VFET pt 2, which
is 10" long, but this one holds 4 TO-3 devices.
When you see people dancing in the street, then the announcement
will have been made.
Well hopefully I don’t miss the opportunity and find them sold out.
With them being your intended size would this chassis still be a viable option?
Will it be a big deal that my high freq compression drivers are 16ohm? When I switch the diaphragms to the radian beryllium variant, it wouldn’t be a big deal to get the 8ohm version if need be.
With them being your intended size would this chassis still be a viable option?
Will it be a big deal that my high freq compression drivers are 16ohm? When I switch the diaphragms to the radian beryllium variant, it wouldn’t be a big deal to get the 8ohm version if need be.
Although people talk about the unavailability of VFET/SIT, there are always Sony TA 4650 amps in operating condition being offered on ebay. These use a single push pull class AB VFET pair and sound great, and they have preamp output/power amp inputs. They sell pretty cheap because nobody seems to appreciate them for some reason. Refurb the caps, input card and power supply cards, and replace the death diodes, and you have a 30 watt VFET amp that sounds fantastic with a bonus preamp and headphone amp, to boot.
I have a couple if 4650, one of which only the preamp works and one in which only the amp works. I suppose someday I will study the chassis to see if a Pass DIY could be put in there if I can ever improve or upgrade my DIY skills to suit. That would be pretty cool to have a Pass DIY or clone VFET in a 4650 chassis. I have heat sinks from a torn down 8650 that bit the dust on many levels.
I also have a couple of pairs of Sony VFETs in working condition, although I don't know how 'good' they are, they are from the earlier generations of Sony VFET amps. It seems most of the PASS DIY use a later generation.
Also, using directly heated triode driver stages (or perhaps Pass DIY Korg B1, don't know, haven't built mine yet) winds up being pretty close to 'the best of both worlds'. I have DHT driver on my midrange ribbon with Sony VFET 8550, Pass DIY clone VFET, and First Watt M2 in rotation. Amazing sound, but the 4650 (non refurb, only death diodes replaced) is not far from the same quality and would be a reasonably priced starting point for somebody who wants to hear what VFET is like.
I have a couple if 4650, one of which only the preamp works and one in which only the amp works. I suppose someday I will study the chassis to see if a Pass DIY could be put in there if I can ever improve or upgrade my DIY skills to suit. That would be pretty cool to have a Pass DIY or clone VFET in a 4650 chassis. I have heat sinks from a torn down 8650 that bit the dust on many levels.
I also have a couple of pairs of Sony VFETs in working condition, although I don't know how 'good' they are, they are from the earlier generations of Sony VFET amps. It seems most of the PASS DIY use a later generation.
Also, using directly heated triode driver stages (or perhaps Pass DIY Korg B1, don't know, haven't built mine yet) winds up being pretty close to 'the best of both worlds'. I have DHT driver on my midrange ribbon with Sony VFET 8550, Pass DIY clone VFET, and First Watt M2 in rotation. Amazing sound, but the 4650 (non refurb, only death diodes replaced) is not far from the same quality and would be a reasonably priced starting point for somebody who wants to hear what VFET is like.
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