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Yes, unless you dedicate yourself to researching and investigating really compatible components… I mean way harder than just high end audio… or you simple love the sound of one companies products together. Then the answer is a good preamp is the heart of a great system. Many people have tried, many people have given up. By the way in general, tone controls don’t perform the function to which they are designed, note high end audio equipment do not have them, and digital processing has basically the same problem. You want equipment that does a very minimum very very well and nothing else. Low end equipment comes with all sorts of buttons and functions. I am sure some day great preampless systems will common… but honestly not for a long time. |
@vanson1 My Benchmark
HPA4 preamp improved the sound of my Benchmark DAC3 HGC. This DAC has a volume control for DAC direct to amp. The preamp improved on the DAC direct to amp on low level volume listening. I used to do a lot of that late at night when the baby was sleeping. You could hear all of the music at low volume with the preamp. Without the preamp there was music missing at the low volume. A rather frustrating listen. I have another preamp that is very interesting for those that want a straight wire with gain. It is the Topping pre90 for about $700. Unfortunately it is incompatible with my current office amp but if it matched I would keep it and sell a 10x more expensive preamp. The only amp that I got it to match was the Benchmark AHB2 amp. However, other people have had more success than me matching amps to that preamp. So if you have a lot of sources, for relatively low cost, you can try this invisible preamp to see if a preamp makes a positive difference. I have Room Correction via ROON Core Convolution files. No need for that in a preamp with a fixed and weak processor. So I have s computer to do the number crunching for DSP. I am not using DSP at the moment but it served me well in the past. |
No surprise the Benchmark pre elevated your system's performance. I have had a few DACs with volume and always thought a good preamp was the heart of a great sounding system Very shortly I will be receiving a new amp, it has two inputs which will allow me to A/B two sources... or two preamps or a source direct vs preamp... I will give direct connection another shot but I think it will still sound better with preamp in the chain..... |
^ This will only inform you as to how it works in your system(s). Not necessarily as a general rule. Ideally you’ll have a DAC with extra available bits for volume attenuation, with a voltage output that matches the input sensitivity of your amplifier(s) for full output. Such a combination will allow for full power output capability of the amp(s) and full range of the volume control without the risk of bit stripping from the DAC. Appropriate interconnects are also needed. |
@twoleftears Yep. All you need is a straight wire with gain and a potentiometer. Amazing that no one figured this out sooner. well i had thought of that ages ago, but what has deterred me is done this way, i can’t easily get an extra $4,000 directional fuse in the signal chain -- and you know how those just make or break a system, ya???? 🤭🤭 |
An excellent preamp is the heart of a system. I went preampless for a while (dac direct to amps; berkley alpha dac and others). NOTHING sounded as good as when I added a Jefff Rowland Criterion preamp. It gave the wood winds wood wind; it gave brass the brass... It basically gave flesh to the musical bones. |
more seriously folks, i will quote @mikelavigne's response in the prior thread on the subject that i referenced earlier if this place had 'stickies' on this subject as posed in the op's question, mike's post would have my vote as the definitive and 'straight to the heart of the matter' reply 09-30-2021 3:19pm you cannot generalize about the importance of preamps as the contribution of preamps to the system performance is all about context and the resolution of the system. |
A lot has to do with your amp. With my Gryphon Mephisto directly from my Emm Labs DV2, too edgy. To much of everything. With the Gryphon Pandora Pre, a much more refined presentation. Call it texture, more musical, all the familiar adjectives. For me in my system it was an easy call. Believe me, I wanted it to work directly from the DV2. I can see in some systems where directly can work but it depends on several factors. |
As mentioned, this has had a lot of coverage here. Assuming you are talking about a line stage and not a preamp with phono, then there are several functions.
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IME this always comes down to cables. I used to know this guy named Robert Fulton who, more than anyone else in the world, founded the high end audio cable industry. He had his special RCA cable that sounded better than the average Radio Shack cable at the time. It was a bit of a revelation... Here we are 43 years later and cables are still a thing. When you run passive controls you are more subject to the coloration of cables. But there was a tech that was developed to eliminate cable colorations. That is the balanced line system, which has a set of standards that have to be met. Most manufacturers in high end audio ignore those standards. So we have audible differences in balanced cables too- sparking the question of whether balanced line cables are even better at all. If the standards were being met this would not be a question! But to meet them, you'll need an active preamp to drive them. You can't do it properly with any passive volume device made. |
Different sound for sure. A dac straight to amp seems to be the most pure way to go. I always found my way back to an active preamp. Just sounded more relaxed dynamic and everything comes in place better. Certain music or even most sounds very good dac straight if a little thin. Detailed for sure though. Rock with lots of cymbals just sounded jumbled in comparison. Is it added distortion? Probably. Don’t care as long as it sounds good. |
Passive preamps do offer resolution but after that, not much else in my experience especially with the BeSpoke passive preamp ($10K). It cannot compete with layering of the sound (vocals - instruments), no space between the instruments & vocals, placement within the sound stage, etc. It just offers a flat sound stage by comparison. Happy Listening. |
Many believe having no active preamp or linestage in the signal path is the “purest” appproach to home audio. However, the electrical parameters of the cables themselves can result in colorations. The balanced line standard Ralph often discusses provides benefits in reduction of common-mode noise and in cable drive abilities (due to noise cancellation) but must meet certain requirements, which would be difficult to meet when using components from different manufacturers, because of differences in impedance and because not all equipment that has balanced connectors is actually a differential balanced design. Some additional information for anyone who is curious. A balanced transmission line consists of two conductors of the same type, each of which have equal impedances along their lengths and equal impedances to ground and to other circuits. |
jasonbourne521,167 posts10-15-2021 10:31amPreamps can look real cool - like my Audio Research SP6! However a passive pot works just as well since most all DACs output 2 volts - enough to drive most all amps into clipping (1 volt needed). Jason is correct here, a little more elaboration below. Many amps are 1.5v or less input sensitivity for full output, and most dacs today are well over 2v output these days, so there’s no problem with being able to voltage drive. And most dacs today have very low output impedance output stages, that are equal to or better than many solid state preamps to drive any capacitive interconnects with, especially bettering most tube preamps. So it’s a furphy to say a preamps drive better than dacs can direct. And like I said if a passive pre has no voltage or impedance issues then it is the next best way. Sure balanced has it’s place in over 3mt interconnect runs, for noise cancelation only, below that there is no need for it. As single ended is just as good, and better in many cases better, as the balanced inputs of many poweramps are just a "balanced opamp" then leading the into the real single ended input of the amp which will sound better. Cheers George |
Not when many poweramps use opamps as their balanced inputs, and then it routes to their single ended input.OK George, by this comment I have to assume that opamps are not a thing with which you are familiar. Opamps (operational amplifiers) have very high gain open loop. Their gain structure is thus defined by the feedback resistance vs the input resistance. When both values are the same the opamp has unity gain. This is a lot of feedback, and most opamps today can support that amount of feedback such that at any frequency in the audio band they will be entirely neutral. And unity gain is how such at thing would be set up, since the amplifier in question would have no need of additional gain when using the balanced input. At any rate, if the designer did execute the opamp input in a substandard manner (and I have seen that), such a thing does not reflect on balanced operation nearly so much as it does on that designer! Take this from someone who made their career in tube electronics, OK? So the sound quality will be unaffected although I do concede that using an opamp solely for this purpose is a poor execution of the amplifier design; better if the amp simply has differential inputs used for either balanced or single-ended operation (and many in high end do exactly that). McCormick and Pass Labs being two examples off the top of my head... |
Preamps are a dinosaur left over from the phono days, when sources had very low outputs and far higher output impedances. They are not needed these days with nearly all of todays sources, except maybe with weak tube output sources. As I and many others say, in nearly all cases they are worse than going direct or using a passive, and a waste of big money for the higher end ones. https://forum.audiogon.com/posts/2262469 Cheers George |
They are not needed these days with nearly all of todays sources, except maybe with weak tube output sources.Sheesh. It was nice when george was off. Now we have rehash this again and again. Tape is still very much with high end audio as is the LP. These media are not served by any DAC I know of. Plus there are active line stages that have better volume controls than I'm used to seeing in DACs. Line stages first started showing up in the early 1990s when the idea of an all-digital system became a thing. Rather than a relic, it seems as if they are not going away anytime soon. If you are going to run a passive control, the best place for it is built into the power amplifier. That way the impedances involved can be far better controlled. But if you have monoblocks it gets tricky. My front end with preamp has 30 feet of interconnect between the amps and the output of the preamp, which also drives a subwoofer amplifier. In this way I keep the front end of the system at a lower level of vibration and I can run a Distributed Bass Array. These are the sort of things you can't do with a passive control. At best, to make those work you have to run short cables- 30 feet is out of the question. If you need dual outputs, you'll instantly be in trouble, and if you want to be finally rid of that pesky standing wave in your room (causing a loss of bass at the listening chair), you'll need a distributed bass array to do it. |
FWIW, and at the risk of appearing wishy-washy and probably not satisfying parties at either end of this discussion, I think both those opposing ends are both right. On the one hand, for some active line stages are liking rolling down hill with one foot on the accelerator and the other foot on the brake. Yet others are grateful that the accelerator is there at all. IMHO, most with existing systems will probably benefit from an active line stage. But, for those building systems, it would probably behoove them to seek out compatible gear that can do without an additional active stage. I’ve tried both ways in the past, and had a very slight preference for an active stage. But, I have confidence that with the more current available products that my future might very well be without an active stage, and I shop accordingly. |
@unsound. Exactly . The problem today is that it adds yet another compatibility issue in an already very difficult matching problem. One more variable can just make a misstep too easy. Assembling a high end system is too challenging for many people already, adding one more level of complexity can be too much. If you have a lot of money and are ok committing to a single product line, or you like the challenge, it can be done. It will become much easier in the future. Especially as analog dies out as a popular pursuit… which at some point it will… but look how much longer that has taken than anyone thought. |
but look how much longer that has taken than anyone thought.About 40 years so far and still counting... And now tape is back after a long hiatus. And we're already to the point where the industry doesn't want to make CDs anymore. For digital, streaming is rapidly becoming the thing; if you're into digital you might have a CD player, a streamer and a mulit-terrabyte drive with DAC... all with different output impedances. Even if the LP dies, which I'm thinking might be about ten years (although there are still advances occurring in that field), active line stages seem to have their work cut out for them. Now if you have a DAC with multiple inputs and a volume control on it, designed to drive an amp directly, the simple fact is you have a line stage with a DAC built in. But like it always works when you integrate things like that, if you want to improve the DAC, you'll be changing the line stage too... |
For the vinyl guys, as many of my customers have found. That even many stand alone phono stages these days, and there are many of them with low output impedance, and enough gain to drive the poweramp via a passive pre directly, that don’t need the extra gain of a mega dollar active preamp in the signal path, with it’s extra distortions, colorations and cost, and their systems sound better for it. EG: just one is, PS Audio’s Stellar phono stage, it has a 72db!! of gain and lower than 200ohm output impedance, https://www.psaudio.com/products/stellar-phono-preamplifier/ this would be great for direct to poweramp via a $39 2 x switchable input 10kohm passive-pre like the Schiit Sys https://www.schiit.com/products/sys Or if you want some tube or ss coloration, and still be able to use it passive as well, the $599 Schiit Freya https://www.schiit.com/products/freya-s Cheers George |
Now if you have a DAC with multiple inputs and a volume control on it, designed to drive an amp directly, the simple fact is you have a line stage with a DAC built in. But like it always works when you integrate things like that, if you want to improve the DAC, you'll be changing the line stage too.I have owned a DAC with a passive VC, but do not remember seeing one with an active stage. I am surprised manufacturers of those DACs with VC don’t provide a unity gain buffered output. Could be a second pair of output jacks, or maybe switched, passive/buffered. The passive crowd wouldn’t see the need, but some might be surprised with the outcome of a direct comparison. |
That’s because most dac’s with VC’s do it in the digital domain, yours was a rare one to have a passive VC on it’s output inside the dac, and that would have had to have been after an active buffer anyway, as if not, then it would have had to be after the I/V (current to voltage converter stage) and that would not have been a good idea.. The ones that have VC’s in the digital domain, all have active output buffers, unity or with gain, as did yours, but it was before the passive VC on the output, what brand model was it?? Cheers George |
mitch2 Interesting, it has to quote: "The clever implementation of the volume control by lowering or raising the reference voltage "in the converters" is something I have never seen before and works flawlessly." " And, its volume control is neither conventional analog nor lossy digital." This to me means you would definitely have an I/V (current to voltage converter) stage after the R2R dac chip set, and then also an output buffer with or without gain. It’s output impedance is <100ohms SE at 2v output, which means it has an output buffer, and is a great candidate for direct to amp connection, and no problem with your SMc monos 10kohm input impedance, they only need 1v in, for full peak wattage output So Mitch, get rid of all those preamps you have
Cheers George |
