I need a digital preamp (optical in, variable RCA out, volume control)

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So I'm pretty happy with my 2.1 system in terms of sound performance.

(see: https://hardforum.com/threads/anyon...eo-any-regrets.1981603/page-5#post-1044490735)

My issue is that the Headphone Amp I'm using is a little cumbersome to switch from HP Amp to Line Out (speakers)

Additionally, the relative volume of the speakers is much higher than the headphones and the volume knob is very slow.

Further, some EQ and sound settings work well for headphones, but not for speakers.

In short, while it physically works, there is a lot of friction and hassle.

I'm looking for a high quality, half width, DAC/Preamp - at a minimum, I want an optical in and a variable RCA out to my power amp.

If it has bluetooth input and supports Amazon HD, all the better.

From what I can tell, the Denon HEOS Preamp will do this:

https://www.amazon.com/gp/product/B00VKCGZNI/

The volume controls are unusual but I think they would be just fine for a desktop preamp:

1585340497082.png


It has a lot of features that appeal to me, but I'm not sure how good the sound quality is (guessing it's fine)

Another option is the Marantz HD DAC1:

https://www.accessories4less.com/ma...hd-dac1-headphone-amplifier-w/dac-mode/1.html

1585340625730.png


Finally, Yamaha has the WXC-50 which seems decent, but the reviews suggest some of the wireless features are fussy:

https://www.amazon.com/Yamaha-Audio-Component-Preamplifier-Silver/dp/B01EI6DQS4/

However, it can run vertical as well as horizontal.

1585340832827.png


Anyway, I'm going to run an optical switch to my current Monolith HPA and also to the Preamp so I can run them independently.

Anyone have any other ideas or suggestions?
 
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You need an optical DAC. The options are near endless, but if you start adding other stuff to the requirements, you're quite likely to arrive at something less effective.

Especially wireless if it isn't WiFi.

So I'd recommend stating your requirements a bit more clearly; the thread is good history, but we kind of need to see exactly what you're thinking, because there may be a better way to go about it.
 
You need an optical DAC. The options are near endless, but if you start adding other stuff to the requirements, you're quite likely to arrive at something less effective.

Especially wireless if it isn't WiFi.

So I'd recommend stating your requirements a bit more clearly; the thread is good history, but we kind of need to see exactly what you're thinking, because there may be a better way to go about it.

An optical DAC with a volume controlled line out. Most of these devices have a headphone jack.

My issue is that my Monoprice HP Amp is great for headphones but a pain for speakers. I need a device that works great with a power amp + speakers and it's fine if it has a crappy headphone jack (or no jack at all) because I just want DAC + variable RCA outs in a small (ish) form factor.

The Denon HEOS has some bad reviews regarding it's sound quality. It was on the list because it could do Amazon HD music, but it sounds like a kludge solution and the PC does it well enough

There are some Chi-Fi devices on Amazon, but it feels like a crap shoot.
 
Well, here's the thing: what are your sources? Is this primarily a PC thing?

Because that's the easiest means of switching. Just have two outputs.

However, I do have a product from Nobsound that I have used to switch between speakers and headphones; call it a passive pre-amp. It also has a volume control, and as it is a balanced design, it's clean.


As for Chi-Fi... most of these are industrial designs, many sourced from Germany, and most use Japanese and Taiwanese components. Topping and SMSL are a few of the best, but there are others. Note the Topping DX7 and DX7s in my sig; these are balanced headphone amps that include balanced line outs, but unfortunately, they do not control line out volume (they're not balanced pre-amps).

I use the Nobsound device as my 'passive pre-amp' for volume control of my studio monitors (the LSR-305s and studio sub wired in series).

In your case, I'd recommend a simple DAC with an in-line pre-amp for volume control.

Anything would do, but something with a decent DAC processor would be ideal, and you don't necessarily need optical unless you actually have two optical sources.

But understanding how that might work for you will require more knowledge of your overall setup and how you use it.
 
Well, here's the thing: what are your sources? Is this primarily a PC thing?

Because that's the easiest means of switching. Just have two outputs.

However, I do have a product from Nobsound that I have used to switch between speakers and headphones; call it a passive pre-amp. It also has a volume control, and as it is a balanced design, it's clean.


As for Chi-Fi... most of these are industrial designs, many sourced from Germany, and most use Japanese and Taiwanese components. Topping and SMSL are a few of the best, but there are others. Note the Topping DX7 and DX7s in my sig; these are balanced headphone amps that include balanced line outs, but unfortunately, they do not control line out volume (they're not balanced pre-amps).

I use the Nobsound device as my 'passive pre-amp' for volume control of my studio monitors (the LSR-305s and studio sub wired in series).

In your case, I'd recommend a simple DAC with an in-line pre-amp for volume control.

Anything would do, but something with a decent DAC processor would be ideal, and you don't necessarily need optical unless you actually have two optical sources.

But understanding how that might work for you will require more knowledge of your overall setup and how you use it.

All sources are optical - main source is PC. I don't want to switch PC outputs - I just want to use the optical out.
I have a matrix optical switch already, not using it at the moment because I only have one source and one target.

I agree I need a simple DAC / Preamp - I just don't know what my options are. The Marantz device would work, but it's kind of a lot and it's primarily a Headphone amp (which I wouldn't be using) so it's not feeling like the best value.
Re-reading that, I think you mean a DAC, then a volume control (like a Schitt Modi + Lyr) - that would work and the Schitt solution is cheap, but I'd really like to just get one device, not two.

This is my current setup and where I want to go:

1585409784019.png
 
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Re-reading that, I think you mean a DAC, then a volume control (like a Schitt Modi + Lyr) - that would work and the Schitt solution is cheap, but I'd really like to just get one device, not two.
This would probably be best. A 'stack' from Schiit would work well, be inexpensive, and you could use double-sided tape or other means to keep the devices in place.
All sources are optical - main source is PC. I don't want to switch PC outputs - I just want to use the optical out.
The main issue I see is that your headphone amp is unsuited for speaker line out pass-through in your use case. I believe I had a difficult time finding the line out on the Monolith previously...

Regardless, this means that you need to 'split' the digital signal at some point prior to the 588, convert to analog, provide a volume control, and output to speakers.

I'd recommend deciding on a balance of aesthetics, utility, and cost. Something like a Modi + SYS or Loki would fairly discretely and inexpensively get the job done.


I also want to head off any potential impression of combativeness I might be giving off -- I am genuinely interested in learning and helping you to find an acceptable solution, and the challenge I see that's nudging my line of thinking toward discrete devices is that on the one hand, devices that do multiple things at the audiophile level are more expensive and still not known to be highly reliable, and on the other hand, dialing back the budget is likely to result in something that really only does what you want on paper, like the line out on the Monolith amp. If we can, it'd be nice to find a solution that actually does what you want it to!
 
This would probably be best. A 'stack' from Schiit would work well, be inexpensive, and you could use double-sided tape or other means to keep the devices in place.

The main issue I see is that your headphone amp is unsuited for speaker line out pass-through in your use case. I believe I had a difficult time finding the line out on the Monolith previously...

Regardless, this means that you need to 'split' the digital signal at some point prior to the 588, convert to analog, provide a volume control, and output to speakers.


I'd recommend deciding on a balance of aesthetics, utility, and cost. Something like a Modi + SYS or Loki would fairly discretely and inexpensively get the job done.


I also want to head off any potential impression of combativeness I might be giving off -- I am genuinely interested in learning and helping you to find an acceptable solution, and the challenge I see that's nudging my line of thinking toward discrete devices is that on the one hand, devices that do multiple things at the audiophile level are more expensive and still not known to be highly reliable, and on the other hand, dialing back the budget is likely to result in something that really only does what you want on paper, like the line out on the Monolith amp. If we can, it'd be nice to find a solution that actually does what you want it to!

The Monolith "works" as a preamp, but yeah - it's not ideal to push1, rotate through 4 options, push2, push2, rotate, push1, push1 every time you want to switch from HP to Speakers or back again.

The Optical Matrix switch is my "digital splitter" - so that's handled.

I like the functionality of the Schitt stack - especially if I add the EQ, but I don't love the aesthetics and they don't go with the Monolith. I could hide the Schitt DAC as it doesn't have any controls I would need to access - I just wish they made a combo device with the DAC and Preout.

The Marantz HD DAC1 is very highly reviewed - it's $750-800 in most places but A4L has it for $450 (refurb, not returnable for refund) and extra warranties are like $35-45.

Here is where it gets nuanced:

I like the Monolith a LOT - it's extremely clear and clean but there is a decent chance that the Marantz would be just about as good with headphones so even though it's a bit higher in price vs other solutions, it could end up replacing the Monolith and allowing me to sell it. The Marantz has both a variable RCA out for an amplifier and a fixed RCA out for perhaps a dedicated headphone amp in case you don't like the one built in.

I prefer a system that lets me keep the headphones plugged in and use some kind of switch to go from headphones to speakers, but after living with this system for a couple months, the plug-in-to-switch scheme would be an improvement.

I do appreciate your help with this - I feel like there must be some solutions that I'm just not aware of.
 
Literally searching for anything that is both DAC and Preamp comes up with... nil.

So to me at least, it's an interesting problem.

On my gaming desktop (9900K in sig), this is solved because the DX7s outputs a line-level signal from the balanced outputs, which I then have a passive pre-amp for. Obviously the Monolith behaves differently.

On my living-room desktop, 8700K in sig, the DX7 (functionally the same) only works as a headphone amp, while the speakers use their own USB input. As the speakers have a quite respectable DAC / amp setup, and they will never be pushed hard, this works marvelously, and for this setup, I have no issue with using the Windows output switching functionality. It's two clicks.

Also, using Windows to switch has an EQ advantage: Equalizer APO recognizes different outputs and switches EQ profiles with output switching in Windows. This is something that has to be done manually on my gaming desktop.


In your case, looking for the capacity to add other sources in addition to your PC and looking to run a second DAC off of optical, this does present a different challenge. I'll keep thinking about it!
 
How about schiit ? a Modi 3 (or mb) with a Sys (or Saga S/+) to add volume control.

I love my bifrost/saga+ combo
IMG_20200318_192318.jpg
IMG_20200328_155705.jpg
That adcom is so tiny compared to my Harmon Kardon Citation 16a, I wouldn't mind that form factor at all ...
 
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How about schiit ? a Modi 3 (or mb) with a Sys (or Saga S/+) to add volume control.

I love my bifrost/saga+ combo
View attachment 233634
View attachment 233635
That adcom is so tiny compared to my Harmon Kardon Citation 16a, I wouldn't mind that form factor at all ...

The Schitt products would do the job, I would just end up with a big stack and a lot of unsightly cables. I could put them somewhere else, but even just adding one more device is pushing my threshold. If Schitt had a single product that was a DAC/Preamp, I'd bite.


Literally searching for anything that is both DAC and Preamp comes up with... nil.

So to me at least, it's an interesting problem.

On my gaming desktop (9900K in sig), this is solved because the DX7s outputs a line-level signal from the balanced outputs, which I then have a passive pre-amp for. Obviously the Monolith behaves differently.

On my living-room desktop, 8700K in sig, the DX7 (functionally the same) only works as a headphone amp, while the speakers use their own USB input. As the speakers have a quite respectable DAC / amp setup, and they will never be pushed hard, this works marvelously, and for this setup, I have no issue with using the Windows output switching functionality. It's two clicks.

Also, using Windows to switch has an EQ advantage: Equalizer APO recognizes different outputs and switches EQ profiles with output switching in Windows. This is something that has to be done manually on my gaming desktop.


In your case, looking for the capacity to add other sources in addition to your PC and looking to run a second DAC off of optical, this does present a different challenge. I'll keep thinking about it!

I get that EQAPO would benefit from different outputs, but the Monolith has extensive EQ, Parametric and DRC settings. I'm happy with just a clean signal to my speakers right now.

Thing I couldn't find out about the Marantz is whether plugging in headphones turns off the RCA outputs or not - the manual didn't say.

A new option is the Bluesound Node 2i - it's a little unconventional, but it has a lot of powerful music capabilities. They even have one with an amp built in - which is actually tempting, except that I would have to give up the crossover in my sub if I went that way - still, it's pretty interesting:

(this is the amp version, but the one I'm looking at is the same thing, just no amp section)
 
https://www.amazon.com/gp/aw/d/B07KG9P3X3/

This looks like a good one. Same dac as the monoprice unit...

Zeos likes it but it has what I would consider to be a fatal flaw. Misclick the knob and you switch it from preout to lineout (max volume).

That's a dealbreaker for me. Too bad.
 
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The Schitt products would do the job, I would just end up with a big stack and a lot of unsightly cables. I could put them somewhere else, but even just adding one more device is pushing my threshold. If Schitt had a single product that was a DAC/Preamp, I'd bite.

You could always get a schiit asgard (or jotunheim, lyr) with the one of the optional dac cards for a dac/preamp/headphone amp in one box but the preamp section only has 1 input and 1 ouput.
I'm not sure how ideal this would be as a solution for you because I feel like the bulk of the price is built into the headphone amps and I assume that your Monolith THX 788 is already great.

 
https://www.amazon.com/gp/aw/d/B07KG9P3X3/

This looks like a good one. Same dac as the monoprice unit...
Yup, as an 'all in one', it's one of the top recommendations. I did look at it earlier in the thread, but I was hoping to find something closer to $100 and I wasn't sure that it would do the preamp job.

Looking at reviews, it does appear to have a 'pre-amp' mode, so while it does more than you want, it's probably the best solution!
 
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Yup, as an 'all in one', it's one of the top recommendations. I did look at it earlier in the thread, but I was hoping to find something closer to $100 and I wasn't sure that it would do the preamp job.

Looking at reviews, it does appear to have a 'pre-amp' mode, so while it does more than you want, it's probably the best solution!

Except for the feature that makes it super easy to turn the pre-out into a max volume line-out and blow your speakers. :(

You could always get a schiit asgard (or jotunheim, lyr) with the one of the optional dac cards for a dac/preamp/headphone amp in one box but the preamp section only has 1 input and 1 ouput.
I'm not sure how ideal this would be as a solution for you because I feel like the bulk of the price is built into the headphone amps and I assume that your Monolith THX 788 is already great.



Yeah, still thinking about the Asgard 3....
 
Well, almost a month later and I still can't figure out which way to go.

There are actually a few 2.1 preamp / integrated amps that are pretty interesting, but everything is hard to get right now with very long shipping times.

Value Leader:
Emotiva PT-100 DAC/Preamp ($299ish) : https://emotiva.com/products/pt-100
1587159181223.png

Pro:
Best price
Excellent sound quality
Meets my minimum requirements

Cons:
Full size footprint
Basic digital and analog inputs only (plus phono which I don't care about)
No bass management


Digital Front End Leader:

SONCOZ CDG1 ($500ish): (https://www.audiosciencereview.com/forum/index.php?threads/soncoz-sgd1-audio-dac-review.10295/)

1587159329088.png


Pro:
Nice digital preamp with exceptional DAC measurments
BT 5.0 (aptx) RX + TX (very cool and rare)
Digital out (to feed my headphone amp)
USB-C input (also rare and cool - easy Note 10 connection)
Half width device
Remote
Available on Amazon

Con:
It ships from Shenzhen
Warranty service and reliability?
No crossover

More expensive units with better bass management:


Parasound New Classics 200 Preamp: ($850ish) https://parasound.com/200_Pre.php

1587159429576.png


Pro:
Analog Crossover / High Pass filter - full range or fixed 80Hz LPF to the sub, adjustable analog HPF to the preouts (very rare)
Good Dac
Assignable input names
Diode Ladder Volume (eliminates pot issues)
Remote

Cons:
Expensive
Full size footprint (17"x14"x2.5") but low profile (1U - 1.75" high w/o feet)
No BT, streaming or connectivity


Outlaw Audio RR2160 2.1 Channel Stereo Receiver/Integrated Amp ($999ish): http://www.outlawaudio.com/products/rr2160.html

1587159579198.png

Pro:
Highly reviewed receiver with excellent sound
Powerful Class A/B Amp
Full analog bass management and crossover (for both sub and mains)
Analog processing loop (to add EQ, etc)
Preouts
Record loop
Tone + defeat
A+B Speakers
Remote
Art Deco Aesthetics (I like them)

Cons:
No BT, basic (obsolete?) connectivity is DLNA and Internet radio (not a big deal to me)
Big (17"x15"x6.5")
It's pretty big
Aesthetics are not for everyone


I'm leaning toward the Outlaw - I'd sell my current power amps and just use it as an all-in one, but it's big and I've been really trying to simplify and shrinkify everything...
 

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Burson does a pre/dac combo with optical.. they are likely the route I will go soon. Good price ranges too from few hundred to thousands. Discreet components are common, roll op-amps, really function over form. Even has a molex on the back of some of their stuff. Enjoy!
https://www.bursonaudio.com/products/
Also worth checking Holton precision audio if you want some good and cheap amps to build up from kit. Usually they will smoke anything 10x the price you buy off-shelf.
 
Burson does a pre/dac combo with optical.. they are likely the route I will go soon. Good price ranges too from few hundred to thousands. Discreet components are common, roll op-amps, really function over form. Even has a molex on the back of some of their stuff. Enjoy!
https://www.bursonaudio.com/products/
Also worth checking Holton precision audio if you want some good and cheap amps to build up from kit. Usually they will smoke anything 10x the price you buy off-shelf.

Those do look nice, but I found a killer deal on an audio swap site for a Parasound Halo Integrated Amplifier - it's the previous gen, but a new one is out of my price range...
https://www.whathifi.com/parasound/halo-integrated/review
http://v2.stereotimes.com/post/parasound-halo-2.1

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I would not get the emotiva or soncoz but I wouldn't mind either parasound or outlaw audio units.
 
I would not get the emotiva or soncoz but I wouldn't mind either parasound or outlaw audio units.

I was this close to ordering the Outlaw RR2160, but saw a cluster of posts from people who had issues with the left channel amp and that made me skittish.

The Parasound was always my preference - it has almost the exact same feature set as the Outlaw, just a higher price point when new and I think it's the best looking of all of them.

The Emotiva unit was reviewed as "good for the price" but for me, it was just too big for what it does - there are tons of tiny 8x8" DAC amps for the same price.

The Soncoz feature set is great and they are loving it at ASR, but... China
 
How do you like it ? I'd assume it's a nice upgrade !?
Is it gonna replace the monolith head amp?
I'd kinda like to eventually upgrade to a high end integrated amp to only have one audio component on my desk.
 
How do you like it ? I'd assume it's a nice upgrade !?
Is it gonna replace the monolith head amp?
I'd kinda like to eventually upgrade to a high end integrated amp to only have one audio component on my desk.

It's fantastic and I'm blown away by how powerful it is. My thoughts, next to numbers...

1. I had heard the headphone section was good, but it's REALLY GOOD. Maybe not quite as good as the monolith, but way beyond what you get in most receivers. The Monolith is going up for sale (as well as my two power amps and my AVR)
2. I did want to simplify the system as much as possible - I was hoping to get something half or quarter size, but this unit is worth the footprint.
3. This amp is 160W into 8ohms, 240W into 4ohms. I can't turn it up past 2 or 3 or my family would revolt (I have a special needs kid who is very sound sensitive) Still, I think the reserve power is nice and the power and energy comes through. Maybe the HIFI crowd would call it dynamics?
4, It has tone controls as well as a sub level knob on the front. Super handy. The tone defeat has some huge relay inside, as does the mute button. Makes that massively satisfying relay sound.
5. I'm not one of those people that hears the differences in speaker cables - quite the opposite. I doubt I could dell the difference between two high quality amps or dacs, but the clarity and power here is startling - I was worried I wouldn't notice. I also worry that it's all in my head - maybe some of it is, but for me, it checks all the boxes - looks, sound, features - all in one.
 
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