Is the Ifi Itube 2 buffer/preamp available anywhere?

I'll just add that I have difficulties understanding why the Ifi device works. After all, it seems to have a pot. In Zero Fidelity (Sean's) review of it, he said it acts as a "line stage preamp". Maybe that has something to do with it?
 
Yes, if you're happy with the 6000A as a preamp, then the Saga+ is probably not the way to go, as you would be feeding your music through two volume controls which wouldn't really be recommended.

That takes you back to the iFi (if you can find one), or either of the X-10D or the Yaqin.
The thing the Ifi has going for it is its versatility -- it offers a number of options such as different tube topologies, 3D and so on. With the other two, one doesn't get to play around much and fine-tune things to one's taste.
 
I think I may have served to confuse matters here, with my basic attempts at explaining electronics. Please note, I am not an electrical engineer by any stretch of the imagination, I am just trying to regurgitate things I have read. I should have caveated with that earlier.

I thought I had read somewhere that a tube buffer increases the current, but I may be wrong. I know that voltage and current are related, so perhaps that doesn't make sense if the voltage remains the same in a buffer.

Gain is normally referred to in voltage terms (or in dB), rather than current.

If you want to do some more reading up about how a buffer works, then the technical term for one is a 'cathode follower circuit'. Note, you can also get non tube-based cathode followers/buffers too.

Putting it back into layman's terms again though, if the unit has a volume control on it, then it's not just a pure unity gain buffer and I would go back to the point that sending a signal through more than one volume control is probably counter-intuitive.
 
I think I may have served to confuse matters here, with my basic attempts at explaining electronics. Please note, I am not an electrical engineer by any stretch of the imagination, I am just trying to regurgitate things I have read. I should have caveated with that earlier.

I thought I had read somewhere that a tube buffer increases the current, but I may be wrong. I know that voltage and current are related, so perhaps that doesn't make sense if the voltage remains the same in a buffer.

Gain is normally referred to in voltage terms (or in dB), rather than current.

If you want to do some more reading up about how a buffer works, then the technical term for one is a 'cathode follower circuit'. Note, you can also get non tube-based cathode followers/buffers too.

Putting it back into layman's terms again though, if the unit has a volume control on it, then it's not just a pure unity gain buffer and I would go back to the point that sending a signal through more than one volume control is probably counter-intuitive.
No. It's not that you have confused things as far as I'm concerned. Matter of fact, your posts have got me thinking and I'm very grateful for that, so don't put yourself down-- it's been enormously stimulating. I read your Tortuga link and sort of got it, but what I realised was that we find electronics so difficult because it's so abstract. For anyone not wishing to read the long screed that follows, I'd advise you to bail out now, okay? I won't be at all offended if you do. It's mostly about my understanding of electronics based on a simpler and more concrete analogy,

A very good analogue for electricity that isn't so abstract is water. I've heard it said that any electrical circuit can be modelled by a water circuit -- and that applies to everything from toasters through hi-fi to computers.

A modern desktop computer is very compact because its components have been miniaturised in the extreme, and very fast because of the inherent speed of electricity. But in principle one could build a water circuit that does everything that a computer can do. The fact it would be the size of a small planet and operate much more slowly is irrelevant to the principle of the thing.

Let's suppose that we have a very large storage tank of water. At the bottom of the tank is a hole through which the water can drain under gravity. The diameter of the hole represents a resistance, preventing the water falling out all at once.

We could use the water coming out, if there was enough of it, and at a high enough pressure, to drive a water wheel whose axle was attached in turn to to a stone wheel for grinding corn.

With more ingenuity, we could introduce a gearbox to vary the power being distributed to whatever device we might choose to employ.

If we think of mains electrical power, analogous to the very large water tank, every device we attach to it is analogous to a drainage hole (or more analogously an extended hole, or tube in other words). The narrower the tube, the more resistance we introduce and the less power would be drawn from the mains. We could have a valve that sealed off the tube, analogous to an electrical switch.

As long as the valve was open, the tube was securely attached, and its walls able to withstand the pressure, it would effectively control how much water runs through it, analogous to how much current is drawn. Very thick copper wires have appreciably less electrical resistance than very thin ones, right?

Water pressure is analogous to electrical voltage; its rate of flow to electrical current; and electrical resistance to the diameter of a connecting tube.

I see a capacitor as being analogous to a smallish water tank. Depending on where it is placed in the circuit, it can determine how much working current comes out the other end. If well-designed, it shouldn't overfill; when full, it will represent a block to the incoming current, i.e. will impede it (hence the term "impedance"?). It shouldn't under-fill, either, so that transients would empty it and the power it supplies drastically reduce for some period of time, however short.

Barring sudden power surges, everything should hold fast and nothing blow a gasket, so to speak. In an electrical circuit, we have an electrical fuse. In a water circuit, a "fuse" would act as an emergency valve and close off the main drainage tube.

What I think the guy is talking about in your Tortuga article is that we will get maximal power the less links we introduce into the sound reproduction chain. The maximum power possible in a hifi system is largely controlled by the preamp. It can never control more power than that maximum. If the power it does deliver is sufficient for the power amp to deal with, all well and good. A passive preamp will do the job.

If not, then we'd have to do something to boost the power, and for that we'd need an active preamp, which, in the water analogy, would be connected to the mains via its own supply tube. But we'd never get as pure a signal as we would if the power was good enough in the first place.

And that's why there's continual arguments about which (active or passive) is better. It all depends on how good the preamp is at delivering sufficient power. If good enough, fine. If not, well, not so good, and all the extra circuitry involved in boosting it is bound to result in a certain amount of degradation of the signal. Hence the aphorism that the best amplifier would be a straight wire with gain.

The product of pressure and current in a water circuit is a measure of its power. Analogously, the product of voltage (V) and current (I) = (VI) is a measure of power in an electrical circuit. And since voltage is itself the product of current (I) and resistance (R, hence V=IR), we can substitute IR for V and end up with Power (W in watts) = I^2R, as I mentioned in my earlier post.

What screws things up for me is what the dickens vaccum tubes have do with anything. It should be possible to use either those or solid state devices to the exact same effect. Indeed, some audiophiles insist that the best SSDs can match or even exceed the capabilities of vaccum-tubed devices when it comes to things like holographic imaging, smoothness, refinement and warmth.

IMHO, my set-up already has very good holography, and images extraordinarily well (but what do I know -- I've never lived with the very best of systems). Is it smooth and refined? Well, I think it is, anyway. Is it warm? Here I must confess I don't really understand what "warmth" means. When people talk about it, to me they often seem to imply there's a kind of trade-off between richness/lushness and detail. They tend to frown on too much detail, and may describe the sound as on the "cool" side and/or analytical, maybe with a tendency to brightness or shoutiness when pushed hard.

Occasionally, you will hear their astonishment at listening to a system that is both deliciously warm and incredibly detailed, usually with reference to very high-end equipment. But you know what? I find my system very engaging, don't analyse much, and just listen to the music.

I have no idea whether others would describe it as "warm" or "cool", or how analytical they would deem it to be. Perhaps mainly through good luck rather than good judgement, I've arrived at my long-term preferred set-up. For all I know, others might think it less than ideal, and they might be right in absolute terms. All I can say is, I'd not be bothered too much if they did.

It may be more a reflection of my inexperience than anything, but would I want to experience anything better knowing that It'd cost an arm and a leg? What would be the point of going beyond what for me is already hugely satisfying, spending money I know I'd be unwilling to part with?

I am, however, interested in spending relatively modest amounts on kit like the iFi just to see what refinements, if any, can be made to my existing system. Hence things like reasonable speaker cables and speaker jumpers, as well as Audiolab's DC Block for the power amp have already been attended to, and their welcome effects been noted. The last remaining niggle seems to be what the iFi will do for me, if anything worthwhile.

Screed over. Apologies if I've taken too much of anyone's time -- but I did warn you! :)
 
I'm interested in the Ifi Itube 2 buffer/preamp, but haven't been able to find it anywhere except where it's out of stock. Does anyone know anywhere where it is in stock? Has it been discontinued, or is there simply a dearth of supply at the moment?

If it has been discontinued, does anyone know of an equally capable tube buffer? And does anyone possess one who might have an opinion about it s/he'd like to share?

TIA
 
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