How important is the pre-amp?

WOW mikelavigne ! You’re in rarified air, or rather the stratosphere. Good on ya. I love the listening room you built.

https://darko.audio/2015/11/the-select-dac-ii-msb-technologys-90000-da-converter/

I used to run a well-regarded passive line state (whose name escapes me) with my McCormack DNA-1, with CD source only, and loved it. McC made their own passive line stage that is still coveted when upgraded by Steve McCormack.

My sources are all digital, and I have thought of either getting one of the Tortuga passive stages (straight wire, no gain) into a DAC and then my amp, or something like the Chord Hugo TT2 DAC using that as the preamp too. And then I think that maybe a tube preamp would be fun, as I’ve never had tubes. But my whole system costs less than an exotic set of speaker cables!

Good thread, but the frustrating part is not being able to mix and match the various options in auditioning pieces (within budget), and trying to dial in the synergy. I have a short list of amps and preamps I like, but I have no idea which ones would play well together if of different brands. Therefore, I wonder if going to an integrated (Pass 60, Levinson, Aesthetix Mimas, Simaudio 600i V2) would alleviate that frustration, and then the DAC becomes the main variable. Hmmm.

The preamp is as important as any other component in the system. If any one component is more important than the rest it would be the listener.

WOW mikelavigne ! You’re in rarified air, or rather the stratosphere.

Actually no, just a few miles outside North Bend, way below Snoqualmie Pass, not even 1200 ft, well within the troposphere.

I wont add too much redundancy to what has been said here. MillerCarbon made me chuckle.

But an overlooked fact is that in the majority of cases the volume and balance controls (essentially two sequential attenuators, so the distortions are doubled keep in mind) are one of the most non-linear and distorting parts of the preamp. Most are in fact pretty bad.

In fact, my current design project is a preamp that eliminates traditional volume potentiometers and replaces them with one of two technologies at different price-points, both are substantially better, and both lend themselves to very nice remote control.

Let’s put aside volume control in the digital domain which has an entire raft of issues, but under the right circumstances can be very good. 99.999% of people have never heard those right circumstances.

Your basic volume (or balance) control is a carbon powder strip with a wiper. It is noisy, prone to dust and moisture, and does not track evenly left to right.

The next step up are Noble/ALPS style, which are still carbon powder, but in a plastic carrier. They are smoother, largely sealed and less prone to issues. They are expensive and in doing so track better left to right. They are still very imperfect.

At the top of the food chain are pairs of discrete, precision, metal-film, low noise resistors. You switch in two matched pairs of these for each volume level - maybe 64 pairs. A smaller number suffice for the balance. Stepped attenuators can cost a HUGE amount due to the labor and the 128 position switches, and are large in size, don’t play well with remote control. BUT computers and relays can come save the day ( as i am doing).

In the middle are what boil down to chips with 128 pairs of resistors that can be switched in and out. They are chips resistors, so imperfect, but i speculated that they are better than the lousy alternative. They can be, but if you use them normally or per the data sheet they are truly awful. It took me many weeks to figure out how to us them correctly. (and a really great chip engineer at the fab firm that made me his fun project).  These are a little complex but overall can be cost effective in somewhat reasonably priced designs - the biggest cost being yet another very quiet power supply (or else.....).

So, the little things are way more complicated than you might imagine. Now that i have prototypes floating around, i can’t go back.

By the way, switches have their own issues, and a preamp does have an amplification stage. If its a Phono (RIAA) it has a very complicated amplifier with up to 2,000X amplification which makes noise a (expletive omitted) nightmare.

So yea, all you need to do is be perfect and it works great.

The preamp is the electrical buffer between yourpower amp and line stage components, volume control, and switch between components.  The separation of the preamp from the amplifier made theoretical sense when they contained phono sections for low output cartridges that needed separation electrical fields from the amplifier output.  Adding another another supply, chassis, and cables increases the cost and complexity.  Well designed integrated amps are plentiful, and popular.  Concerning dacs,  be sure that there is a true volume attenuators in the output stage, and not just truncated digital paths