@mitch2 I have owned a few pieces of Steve’s equipment, including his original line drive unit ( which I understand was not buffered ). I still always preferred a preamp. Maybe I should try a device as you are suggesting. BTW, I always read your commentary ( which is again why I questioned the receiver / integrated amp thing a while ago on that thread ). I do not claim to be the smartest guy with this technical jargon as many of you seem to be, but I do have an understanding of much of it. I am, and have been, an audio guru to many, with my many years in this hobby, including professionally, and the ability and experience to use and trust my ears ( and thankfully, they are still working in my mid 60s ), and that is what I go by. Thank you, Enjoy ! MrD.
How much do I need to spend to get a preamp that sounds better than no preamp?
Hello all.
I'm using an Audible Illusions L1 preamp and I think my system sounds better when I remove it from the signal path. Oppo BD105 directly to SMC Audio DNA1 Gold power amp. I have read that there is level of quality you need to hit before there will be an improvement in sound. I can't seem to find what that level is. Any ideas?
Thanks in advance,
Ben
I'm using an Audible Illusions L1 preamp and I think my system sounds better when I remove it from the signal path. Oppo BD105 directly to SMC Audio DNA1 Gold power amp. I have read that there is level of quality you need to hit before there will be an improvement in sound. I can't seem to find what that level is. Any ideas?
Thanks in advance,
Ben
403 responses Add your response
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Regarding Steve’s McCormack amplifiers, I believe all of them originally had a 100K ohm input impedance, up to the DNA-500, which was designed with a 10K ohm input impedance.Yes these lower (10kohm) later amps will not be a good match for passives. But! as the OP used it, direct from a 100ohm source to amps, no problems so long as the input sens is still 0.8v or even 2v for full output, it will to many still sound better than any active preamp, with or without gain. Cheers George |
Yes Audible Illusions are a very good active preamps, I owned an AI 3A and loved it. They did run the tubes very hard in it though, you don’t get much life out of them, I’ve always believed that’s why it sounds as good as the best active preamps I’ve heard. But the OP and me, going direct sounds the best for transparency and dynamics, and to me and many others a well implemented passive comes in a very close second. To me any active stages add colouration's and cannot improve on the dynamics against a well implemented passive, they can only detract as they have no dynamic range expander circuit in them, and they wouldn't want to as they sound rubbish. Cheers George |
honashagen OPI would do it so the "master volume control" is around 3 o’clock for normal listening level. That gives you leeway up or down for louder listen or quieter recorded music. Cheers George |
Hi George You are making an assumption in your last statement: That an impedance value is all that matters. Unfortunately, the universe is not quite that simple. The type of output stage that provides the "100 Ohms" impedance (not resistance...) plays a huge role in the frequency domain performance, which is ultimately what we care about with music as the signal. At one single frequency, you may indeed measure 100 Ohms, like say at 1 KHz (a popular choice). But this value is made up of resistance, transistor gain effects, and parasitic capacitance, of which the latter two are extremely sensitive to frequency, and temperature, and are intimately tied to the circuit design and its parts. One of the goals of an amplifier designer is to minimize these effects through a combination of clever design techniques that have proven their mettle. However, not all output stages have the same frequency response (i.e., impedance at all frequencies). In fact, there are hundreds, if not thousands, of topologies and permutations, and they all have varying limitations. Some are good, some are ok, some are mediocre, and none of them are perfect. Which you get depends partly on design budget, but mostly on the engineer's design experience. But wait, there's more: it is the same story for the input impedance of the amp or preamp! Then, when you combine them together, they will interact in yet a third (new) way! Especially with complex signals like music. So, at the end of the day, it's a crap shoot. There really is nothing definitive in this crazy world we live in. With a preamp might better, might not, have to insert a human in the feedback loop and check. But then that simply becomes their opinion, and how definitive is that? |
“No preamp” is a straight wire. It will add no noise, no distortion, and in 99.9% of cases no frequency response anomalies. There is not a preamp made that has the same characterics. Thus, there is no amount of money that can be spent on a preamp that will sound better that a straight wire. There are reasons someone might prefer a preamp to a plain interconnect. These include gain, impedance matching, and pleasurable distortion. Personally, I have retired my preamps (I have three to choose from) and have my DAC connected directly to my amplifier. It is better. |
Hi OP The gain control is varying the tube's circuit gain. The volume control varies the level of the input signal. They are completely different animals. You can just put the gain control at some random point like 3:00, but is that the optimal point? Not clear. One would need to know a lot about the circuit design to make that call. I'm not surprised AI isn't getting involved in the answer, as it can be quite complicated. It's also why few amplifiers actually have gain controls (except for vintage ones, and that was because of the wide variety of speaker efficiencies back then). My suggestion is that you try a range of settings. There is likely to be one spot you prefer for a 'given volume level.' Most gain circuits have a sweet spot. It will still work outside of that range (since they made it available to you to adjust) but it won't necessarily work as well (e.g., less linear). What I do is listen one night with it turned all the way up. Then the next listening session, turn it most of the way down. Use the volume control to set the music at about the same level for both sessions. Then try turning it to the midpoint, then vary from there, etc. Trying the two extremes first will help you "frame" a reference point to fine tune the setting. My MC240 clearly sounds its best between 1:30 and 2:00, but your results could be completely different. |
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Replace your amplifiers with a wire and let me know how that works out for you.Since I listen to speakers, my DAC doesn’t have enough current output to make much noise, so I think I’ll keep my amplifiers (my speakers are bi-amped). My preamp wasn’t doing anything useful, as the DAC has enough output to drive the amps and the speakers to 100+ dB peaks. The preamp was only adding noise, distortion, and frequency changes. |
Hi Phomchick If you have enough gain, drive, and power bandwidth from one single amplifier stage, then that's great. Like I said, it's up to the human in the feedback loop to make the call. But to be fair, you most likely have more than one stage of amplification already built into your source and amp. They just didn't tell you it's there. |
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phomchick+1, But there are others that live in denial, even if they can do with good impedance and gain matching. A buffer or gain stage added to a passive with good impedance and gain match can only add distortions/colourations. Cheers George |
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There's no technical reason to conclude getting gain in a pre-amp stage won't sound better.Sure there is. Gain means an active circuit. And all active circuits add noise, distortion, phase and frequency distortions. If you don’t need the gain from the preamp, you can avoid these problems by eliminating the preamp. |
My point was that one way or another, you do need gain, no matter what you want to call it, or which box you think it should be in, or not be in. Most amps have 2 or 3 stages of gain, even if you think there’s only one. Also, a volume control will add noise, crosstalk, and phase error. You don’t need gain to screw things up. And some volume controls do more damage than multiple amp stages would. Ben - you’re welcome! Let me know how it goes. |
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You can just put the gain control at some random point like 3:00, but is that the optimal point? Not clear. One would need to know a lot about the circuit design to make that call. I’m not surprised AI isn’t getting involved in the answer, as it can be quite complicated. It’s also why few amplifiers actually have gain controls (except for vintage ones, and that was because of the wide variety of speaker efficiencies back then).I would have thought the least amount noise would come if the master is at or near full for loud listening, then the gain level if it is controlling the "tube gain" it’s then only increasing any noise to a minium level, as tube noise/distortion increases at the same rate as the gain will. Cheers George |
Just bought the McIntosh C47 preamp, very similar in performance to the C52 that was reviewed in the latest TAS. Very nice, much better than going straight from my dac to the Classe monoblocks. Plus I needed preamp since I also have a tt and a cd/SACD player. When Going straight from the dac into the amp, the sound seemed lifeless. The preamp has made the SQ come alive, more spacious and the instruments are more articulated/distinct. |
Keep in mind, there are no right or wrong solutions here but rather what the Op likes. We could give scientific measurements from now on (don't think for a minute they are not appreciated) but you already know it really comes down to what the OP perceives as the best sound, at least to his ears. Apparently he likes the dynamics of an active preamp ( like his L1) but again I would consider the McCormack passive preamps as an alternative for greater dynamics. The audible Illusions L1 offers a really good sound for the price and for some reason much of the competition in its price range don't come close. Yes they can be a bit hard on tubes. When I had mine I ran the same tubes for two years without failure but most of you know that many of the NOS tubes are not durable enough to last without premature failure. So it really comes down to using durable tubes or at least what is recommended by the mfg. Another thing to consider is that even though you might turn the power off the tubes are still lite at a lower voltage . |
I forgot to mention that when you purchase an Axiom passive preamp the mfg will ask you what power amp you will be driving so that it can be configured to deliver the best sound. When you buy a used one on the internet it may be designed for a different amplifier and you might not experience the best possibble sound and dynamics you would expect. Just a thought. |
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That doesn’t even make logical sense. Read again sunshine, maximum master volume with minimum "tube gain" for loudest listening level. Will give lowest noise figures I forgot to mention that when you purchase an Axiom passive preamp the mfg will ask you what power amp you will be driving so that it can be configured to deliver the best sound.That would be say a 100kohm passive for amps like many Rogue Tube amps which are 1mohm input impedance. Or at the other end maybe a 5kohm passive for amps with 20kohm input impedance. And then some in between these. |
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Maybe it's time to try an integrated? Audio is like religion and politics. The more I learn the less fun it seems to be. Back in the 70's when I had a Crown pre and a DC300 power amp and a graphic EQ and some kind of time aligned speakers with white woofers that looked like coffins, I remember be elated by the sound. I want that feeling again. |
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it will to many still sound better than any active preamp, with or without gain.This statement is false, on account of the word 'any'. "Some' would make it accurate. A buffer or gain stage added to a passive with good impedance and gain match can only add distortions/colourations.This is a common myth. The problem is that passive controls can do this too. So the trick is to figure out what works in your system- and the vast number of options is why this is so tricky. I would have thought the least amount noise would come if the master is at or near full for loud listening, then the gain level if it is controlling the "tube gain" it’s then only increasing any noise to a minium level, as tube noise/distortion increases at the same rate as the gain will.Most active tube line stages are not built in this manner, since the volume control has to be before the active gain stage in order to prevent overload. So the noise floor of a tube line stage if well-designed will be a constant. And just so we're clear about that noise floor, on speakers of 105db, to even hear a good tube line section's noise floor, you have to put your ear as far in the midrange horn as you can just to hear it. IOW its a non-issue, as most people don't use horns (which are the only speakers that are that efficient) anyway. Sure there is. Gain means an active circuit. And all active circuits add noise, distortion, phase and frequency distortions. If you don’t need the gain from the preamp, you can avoid these problems by eliminating the preamp.There are four functions that any line section/preamp should be able to do, and this includes passives except for the first point below:1) add any needed gain2) control volume3) select source4) control the interconnect cable between the preamp and amp Of these, point 4 is the least understood, even by preamp manufacturers. It is certainly misunderstood by all passive control manufacturers (unless they are in it solely for the money, and some are as we have seen earlier on this thread)! If you are wondering how a passive can have more coloration than an active, its due to point 4. This is because the interconnect cable can impose an artifact as we all know, since the cable industry is a multi-billion dollar/year industry in the US, and everyone reading these words has heard cables make a difference in their system. But if the preamp is properly designed this does not have to be the case. BTW, this is what the balanced line system was devised to do and it is very successful if one adheres to the balanced line standards. But a properly designed single-ended line section can reduce cable interactions quite dramatically as well. **No passive** can do that! The reason I quoted the latter post above is that most sources make no provision for cable control- and thus are subject to cable artifacts. If the manufacturers of source components had their act in gear, we would not be having this conversation! “No preamp” is a straight wire. It will add no noise, no distortion, and in 99.9% of cases no frequency response anomalies.It is now easy to see that the above post is false. Its based on the idea that cables have no artifacts, also leaves out the effects of capacitance and the like that are inherent in cables and makes the false assumption that a volume control is somehow the same as a straight wire, which it certainly is not! As a result, you can actually have an active line section with wider bandwidth that can indeed sound better than a passive and not due to 'pleasant distortions' either (since any properly designed active line stage will have vanishingly low distortion), but instead due to the additional transparency offered by cable control. The distortions created by amplifiers are far more significant! |
It’s always nice to have something to argue against, but in my case, you are setting up a straw man consisting of a passive volume control and a high impedance output to the next stage.“No preamp” is a straight wire. It will add no noise, no distortion, and in 99.9% of cases no frequency response anomalies.It is now easy to see that the above post is false. Its based on the idea that cables have no artifacts, also leaves out the effects of capacitance and the like that are inherent in cables and makes the false assumption that a volume control is somehow the same as a straight wire, which it certainly is not! As a result, you can actually have an active line section with wider bandwidth that can indeed sound better than a passive and not due to ’pleasant distortions’ either (since any properly designed active line stage will have vanishingly low distortion), but instead due to the additional transparency offered by cable control. The distortions created by amplifiers are far more significant! My volume control is the internal volume in the JRiver Media Center 64 bit DSP. My DAC has a volume control, but I keep it at 0 dB attenuation. The DAC has a low impedance balanced XLR output that goes directly into my amplifier. So while you can make good arguments against passive volume controls and uncontrolled cable interactions, these are not a factor in my system. Thus, in my system, my statement above that there is no amount of money that can be spent on a preamp that will sound better that a straight wire, is a perfectly true statement. I also think that the distortions caused by active circuitry are far more likely to cause audible problems than a passive volume control hooked up to a patch cord. Though that isn’t an argument that can be settled without specifics which are not available here. But I feel that I am on pretty solid ground in saying that anyone hooking their moderately well-engineered DAC up to their amplifier without any passive components between the two will get better sound than they would get by adding an active (or passive) preamp to the mix. This will be the case for most people, and was the scenario painted by the original post. |
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So while you can make good arguments against passive volume controls and uncontrolled cable interactions, these are not a factor in my system. Thus, in my system, my statement above that there is no amount of money that can be spent on a preamp that will sound better that a straight wire, is a perfectly true statement.@phomchick I agree on the first sentence 100%. But not on the last; most high end audio manufacturers don't support the balanced standard even though XLR connections are used (and to be perfectly clear, I'm not sure whether that includes Oppo). So if you were to add a buffer or active line stage that *does* support the balanced standard, you *may* find that it is an improvement. If you have to audition the cables to get it to sound right, that's a clue that the balanced standard isn't supported. |
"6 XLR Balanced Audio OutputSo while you can make good arguments against passive volume controls and uncontrolled cable interactions, these are not a factor in my system. Thus, in my system, my statement above that there is no amount of money that can be spent on a preamp that will sound better that a straight wire, is a perfectly true statement.@phomchick I agree on the first sentence 100%. But not on the last; most high end audio manufacturers don’t support the balanced standard even though XLR connections are used (and to be perfectly clear, I’m not sure whether that includes Oppo). So if you were to add a buffer or active line stage that *does* support the balanced standard, you *may* find that it is an improvement. "XLR balanced connection offers better common - mode noise rejection and improved signal quality over the RCA connection. If your preamplifier, power amplifier, or active speakers offer XLR balanced inputs, you may use a pair of XLR audio cables to connect the ******** DAC’s XLR Balanced Audio Output to the XLR input of your device." @atmasphere are you now willing to say that both my statements are 100% true? :-) |
Aside from some technical points made throughout this thread which I find educational, I think the overall conclusions drawn are based on an assessment ultimately made by the listeners’s ears which are subjective by definition. There’s also an an additional degree of confusion since the two different scenarios of source direct to amp and using a passive preamp in between the two seem to be used interchangeably. It would be more useful to just take a poll and tally the results. And I’m willing to bet my last dollar that most people including me will prefer an active linestage between the source and the amp vs. going direct from the source. |
XLR balanced connection offers better common - mode noise rejection and improved signal quality over the RCA connection. If your preamplifier, power amplifier, or active speakers offer XLR balanced inputs, you may use a pair of XLR audio cables to connect the ******** DAC’s XLR Balanced Audio Output to the XLR input of your device.@phomchick No, there is no way to tell from the above whether the unit supports the balanced standard or not. Here is the standard in a nutshell: 1) pin 1 is ground, pin 2 non-inverted, pin 3 inverted (the latter two are reversed in Europe) 2) the signal travels in a twisted pair usually within a shielded cable. 3) Ground is ignored by both output and subsequent input; it is used for shielding only. 4) The output is capable of driving low impedances of 2000 ohms or so without distortion or loss of bandwidth (in particular in the bass). Of these four points, the latter two aspects are generally ignored by high end audio. This causes the cables to exhibit artifacts where they otherwise would not. Here’s an easy test, which many balanced components fail. If you connect to an output XLR, using only pins 1 and 2 and get a signal with no hum or buzz, the standard is not being supported. This is because the return circuit for pin 2 is ground rather than pin 3. If the unit supports the standard, there won’t be a circuit between ground and pin 2 or 3, and with no circuit you get a buzz. |
Back to the original question from the op - The BD105 is sort of a streamer DAC plus a digital preamp right? I am curious what quality of digital music the op is playing? if its high res - perhaps the digital volume control is more forgiving to the overall sound quality? What if a lower resolution music like spotify or apple music is played on BD105->Amp setup? Just curious! As someone else mentioned - to a newbie this is all good learning for me - but ultimately its whatever his ears tell him thats the truth! |
since the volume control (THE MASTER!!) has to be before the active gain stage in order to prevent overload. So the noise floor of a tube line stage if well-designed will be a constant. So the noise floor of a tube line stage if well-designed will be a constant. This is total BS, yes the "Master Volume" is in front of the active gain stage and should be at or around 2-3 o’clock for normal listening, 5 o’clock or nearly full for loud, and 12 o'clock for low listening. If the active gain stage has a "gain control" as in this case, and has it’s gain increased so then the "Master Volume" is at 9 o’clock for normal, this will increase noise, distortion and whatever other non linear distortions the active stage has, sent to the amp, hence to the speakers. Cheers George |
Note: The words THE MASTER!! were added to my post after the fact.since the volume control (THE MASTER!!) has to be before the active gain stage in order to prevent overload. So the noise floor of a tube line stage if well-designed will be a constant. So the noise floor of a tube line stage if well-designed will be a constant. George, your post here is incorrect. Clearly you don’t work with active line sections or you would know that. If anything, turning down the volume will cause the gain stage to have less noise. This is because the input is getting closer and closer to a dead short as the volume control is turned down. And we all know that an active gain stage is at its least noise level with the input shorted... If you look at most active line sections, the balance and volume controls exist prior to the actual gain stage of the line section. It is very rare for the controls to be anywhere else! |
Note: The words THE MASTER!! were added to my post after the fact.I don’t care when it was added. As the "volume control" is always the "Master", just thought I’d drive it home to you. Clearly you don’t work with active line sections or you would know that.Of course I do, don’t be ignorant, if you increase the gain of an active stage you increase not just the signal what’s coming in but everything else including noise, rf ,hum any tube or transistor noise is also amplified when you add more gain to an active stage. Cheers George |