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Are pre-amps necessary

MattHooper

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I've tried passive pre-amps before, and also some DACs that offered volume control (e.g. an old Meitner DAC and my current Benchmark DAC).
Whenever I ran a DAC directly in to my amps (monoblock tube amps) instead of whatever pre-amp I had on hand, I was always struck with the sense of clarity and smoothness...the impression of very "direct, uncolored" sound going straight in to the amps to my speakers. Problem is I always gravitated back to an active pre-amp because for whatever reason the direct signal to my amp from a DAC seemed to lack the same body/density of sound and I found it unsatisfying after a while.

Problem is that just remains subjective anecdote and there was no easy way to blind test between the DAC using volume control directly in to the amps vs using my pre-amp.
 

March Audio

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Hello Burning Sounds,

Very nice to see you here again. I highly appreciate your above post since your system design is quite similar to my current project;
https://www.audiosciencereview.com/...oftware-crossover-and-multichannel-dac.12489/

It is very nice of you giving us info of "Roon doesn't have this functionality and one of the reasons I rejected it when I had a long trial". As I informed you several days ago, I use mainly JRiver and Roon, and after hearing your comment here, I should be much careful when I would use Roon in my trials.

You would please let me ask your thoughts regarding possible "bit loss" in digital processing, especially in case of "low gain" situation.
Its true it doesnt have a "start up" volume setting but it has never restarted with anything other than the previous volume setting in my experience. So a bit like an analogue volume pot. If you left it at full blast then thats what you will get ;) It also has volume limit controls so you can set a maximum.

1587265218123.png
 

Puska

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yes it does have tubes. based on some advice I had in the past I thought it was the cool thing to do. I had also been looking for tube preamps a few weeks ago.
hence finding this site and reading more about the "tube" effect. I decided to scrap that idea. So thank you.

I had some money to spend so I was looking at the matrix x-sabre. Call it a delayed present. I just cant decide if i need the MQA version and yeah I have read multiple opinions on mqa already.

I was also looking at the RME ADI-2 that was mentioned in the next post. Which is much cheaper. And cant decide between the 2. I presume they would both work well as a combined pre/dac option.

Paying less is obviously better but I am just trying to decide if an extra 500 bucks will get me something worth that extra coin. My budget range seems to be in the 1k-2k range. and skipping the preamp upgrade now free's up more money for a better dac.
Is topping d90 + Schiit Freya S better then topping d90 alone?
 

Tks

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Is topping d90 + Schiit Freya S better then topping d90 alone?

How could it be? The D90 is virtually the best known DAC currently on the planet (aside from potentially the Stereo 8 Okto Research DAC being teased). Any addition to the D90 in the digital signal chain is going to be a bottleneck to it if it doesn't have better performance than the D90, which the Freya doesn't unless it's being used in passive mode.

Aside from connectivity.. I honestly don't even know what the point of pre-amps are in the modern day with the sorts of DACs we now have. Just seems like something passive speaker setups find convenience with.
 
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T

thejck

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does the d90 function well as a preamp for volume control? i dont have any other inputs I care about
 

RichB

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Its true it doesnt have a "start up" volume setting but it has never restarted with anything other than the previous volume setting in my experience. So a bit like an analogue volume pot. If you left it at full blast then thats what you will get ;) It also has volume limit controls so you can set a maximum.

View attachment 59379
Power on volume is a useful feature for any digital controlled volume control. Oppo did it on their UDP-20x players and even on their analog pot in the HA-1.

- Rich
 

mocenigo

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Digital attenuation is less about loss and more about noise floor. A 16 bit stream can represent a dynamic range of 96 db, hence it has a noise floor of -96 db.

Wrong. Google (or search here) what proper dithering can do. Otherwise DSD would have a dynamic range of 6 db.
 

Fluffy

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Wrong. Google (or search here) what proper dithering can do. Otherwise DSD would have a dynamic range of 6 db.
I know what dithering does, what's your point? do you deny that that effect of lowering bit depth is increased noise floor? DSD works because it's at incredible sample rates. No amount of dithering would make 1 bit audio at 44.1khz sound good.
 

Burning Sounds

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Its true it doesnt have a "start up" volume setting but it has never restarted with anything other than the previous volume setting in my experience. So a bit like an analogue volume pot. If you left it at full blast then thats what you will get ;) It also has volume limit controls so you can set a maximum.

Yes, you are absolutely correct about the settings in Roon - in the days of using an analogue pot I would always turn it down before turning off so that I knew the system was like that at switch on. It was a habit you got into. You can turn Roon down before you switch off too, of course and it will be at that setting when you turn it back on. With JRiver you don't have to. I guess after many years of JRiver doing this automatically I found it a bit of a surprise that Roon didn't do this.

When I gave Roon some feedback they did say they would look into this feature and I've noticed on their forum that other users have commented that they would like the application to do this.

@dualazmak I'll respond to your query about gain on your mutlichannel thread so as not to clutter up this pre-amp thread. As I'm sure you are already aware getting gain staging correct on software DSP is critical to avoid digital clipping.
 

mocenigo

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I know what dithering does, what's your point? do you deny that that effect of lowering bit depth is increased noise floor? DSD works because it's at incredible sample rates. No amount of dithering would make 1 bit audio at 44.1khz sound good.

I am speaking of 16 bit 44.1khz.
 

majingotan

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I've tried passive pre-amps before, and also some DACs that offered volume control (e.g. an old Meitner DAC and my current Benchmark DAC).
Whenever I ran a DAC directly in to my amps (monoblock tube amps) instead of whatever pre-amp I had on hand, I was always struck with the sense of clarity and smoothness...the impression of very "direct, uncolored" sound going straight in to the amps to my speakers. Problem is I always gravitated back to an active pre-amp because for whatever reason the direct signal to my amp from a DAC seemed to lack the same body/density of sound and I found it unsatisfying after a while.

Problem is that just remains subjective anecdote and there was no easy way to blind test between the DAC using volume control directly in to the amps vs using my pre-amp.

Seeing an extra box gives you a false sense of "better sound" due to extra distortion to the signal that active preamp is adding. It's the same reason subjectivists add a tube preamp to the chain as those distortions can provide a sense of "fuller" sound. Nothing wrong with preferring the distorted sound (I do as well as I use my OG Saga tube preamp) though claiming that the sound is better is definitely fooling themselves. A big caveat, however, is to perform a 19/20 correct choice DBT volume matched test to ensure that we have objective proof that those distortions added to the chain are audible, and if we don't pass the test with 95% confidence then it's all psychoacoustics warping our sense of hearing (I believe the latter is 100% the case)
 

Fluffy

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I am speaking of 16 bit 44.1khz.
Still, there's nothing wrong with what I said. A normal undithered 16 bit signal has a noise floor of -96 db, that's just the maths. You can push it lower if you must using dithering, but what's the point really? Just use 24 bit if you need the extra headroom, Any hardware today can handle that effortlessly. Not that there is any practical need for a dynamic range larger than 96 db.
 

mocenigo

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Still, there's nothing wrong with what I said. A normal undithered 16 bit signal has a noise floor of -96 db, that's just the maths. You can push it lower if you must using dithering, but what's the point really? Just use 24 bit if you need the extra headroom, Any hardware today can handle that effortlessly. Not that there is any practical need for a dynamic range larger than 96 db.

You said “A 16 bit stream can represent a dynamic range of 96 db, hence it has a noise floor of -96 db.” you were not specifying “undithered signal”.
 

MattHooper

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Seeing an extra box gives you a false sense of "better sound" due to extra distortion to the signal that active preamp is adding. It's the same reason subjectivists add a tube preamp to the chain as those distortions can provide a sense of "fuller" sound. Nothing wrong with preferring the distorted sound (I do as well as I use my OG Saga tube preamp) though claiming that the sound is better is definitely fooling themselves. A big caveat, however, is to perform a 19/20 correct choice DBT volume matched test to ensure that we have objective proof that those distortions added to the chain are audible, and if we don't pass the test with 95% confidence then it's all psychoacoustics warping our sense of hearing (I believe the latter is 100% the case)

Have you tried a DBT with your tube gear?

(BTW, if we are talking about audible addition via tube gear, I wouldn't say one would have a "false sense of better sound" if that is what "sounds better/is preferred" to the individual. I haven't DBT's my tube gear, but if it is altering the sound as I perceive it, to me it "sounds better" than when I used SS gear. In any case, I enjoy owning the stuff and if my perception is influenced by knowing my tubes are in the system, I'm ok with benefiting from the effect :))
 

majingotan

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Have you tried a DBT with your tube gear?

(BTW, if we are talking about audible addition via tube gear, I wouldn't say one would have a "false sense of better sound" if that is what "sounds better/is preferred" to the individual. I haven't DBT's my tube gear, but if it is altering the sound as I perceive it, to me it "sounds better" than when I used SS gear. In any case, I enjoy owning the stuff and if my perception is influenced by knowing my tubes are in the system, I'm ok with benefiting from the effect :))

Not possible with the Schiit Saga (unless I have two units) because tube mode and passive mode have different volume levels on the same pot position. The tube mode is slightly louder and that louder volume helps with the psychoacoustic effect of perceiving the sound as more engaging. The tube may or may not alter the sound but it will alter it in a way that is never objectively better (just look at measurements). Just to my subjective preferences, louder = more engaging and the active tube output certainly delivers that compared to the transparent passive mode. Hypothetically, if there are two Sagas in my system and are playing at the exact same volume, I definitely would fail DBT test with random guessing results
 

Mnyb

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What kind of Tube power Amps ? Do they provide the benign easy to drive input impedance you see in most SS power Amps . The preamp may be needed .

Don’t forget if the equipment is “audiophile” enough the normal “rules” may not apply
 
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