Volume Control between DAC and Power AMP

[gabrielb]

Hi,
I got Benchmark DAC3-B and recently I ordered Benchmark AHB2 Power Amplifier to replace my Roksan Caspian2 integrated AMP.
I'm using a single source a dedicated music PC running foobar2000->DAC3B->AHB2->Gamut PHI-5
I looking for an advice on how to control the volume:

1. Control the volume digitally with foobar (the vast majority of my content is 16bit so that leaves 8 bit to control the volume)
2. Resale my DAC3B and get the DAC3-L with a *digital* PRE function
3. Use my old Antelope Zodiac+ PRE function with XLR IN/OUT or use the Roksan Caspian2 PRE function (RCA IN / XLR OUT)
4. Get a dedicated PRO volume control like Goldpoint SA1X/SPL Vol2/Khozmo/...
5. Get a fully functioning PRE like Benchmark LA4

Currently I'm leaning towards the second option (selling my DAC3B and getting a new DAC3L with digital attenuation).
I don't expect to see a real difference between option 1 (foobar2000) and option 2 (Benchmark digital attenuation), but it is nice to have a physical knob to control the volume and I like having a remote to switch between digital sources (allowing a new digital in from a BT receiver).
It will also protect against full power system sounds (which are currently disabled) if something goes wrong ...

Can a dedicated PRO volume control from the PRO-AUDIO domain ($1000 or less) match or improve over the digital volume control?

I assume the best option is getting the Benchmark LA4 PRE, but it is almost $3000 and I don't have any analog input to justify it.
Will it be *significantly* better than the other options?
My current speakers are Gamut-Phi5 which will be upgraded sometime in the next few years...

Thanks
/gabriel

 

[gfinlays]

Were it my money, I'd resale the DAC3B and pick up a used DAC3L or DAC3HGC (these seem to be more commonly available to buy used).

The hybrid gain control will outperform any passive attenuator. Digital attenuation is performed in 32bit. That's a lot of signal attenuation before you get anywhere near affecting Redbook resolution.

A pro audio attenuator is a lot of cash for what is basically a few stepped attenuators, which will ultimately become noisy as the wiper contacts wear.

The "benefits" of the LA4 Pre over the DAC3L are properly splitting hairs. Barely measurable and completely inaudible. As you said, without any analog inputs needed, it's very hard to justify.

I have a DAC3HGC and HPA4. The latter was purchased to make it easy for my good lady to switch between music playback from Roon and sound from the TV, which is fed out from the TV's TOSLINK to a DSPMini which does a close facsimile of the room correction convolution filters applied in Roon. It's easy for her to see from the giant customisable display which source is selected. Source selection on the DAC3 is not obvious to the less technically inclined.

Expensive, but for the sake of marital bliss, it was money well spent!

 

[gabrielb]

Were it my money, I'd resale the DAC3B and pick up a used DAC3L or DAC3HGC (these seem to be more commonly available to buy used).

The hybrid gain control will outperform any passive attenuator. Digital attenuation is performed in 32bit. That's a lot of signal attenuation before you get anywhere near affecting Redbook resolution.

A pro audio attenuator is a lot of cash for what is basically a few stepped attenuators, which will ultimately become noisy as the wiper contacts wear.

The "benefits" of the LA4 Pre over the DAC3L are properly splitting hairs. Barely measurable and completely inaudible. As you said, without any analog inputs needed, it's very hard to justify.

I have a DAC3HGC and HPA4. The latter was purchased to make it easy for my good lady to switch between music playback from Roon and sound from the TV, which is fed out from the TV's TOSLINK to a DSPMini which does a close facsimile of the room correction convolution filters applied in Roon. It's easy for her to see from the giant customisable display which source is selected. Source selection on the DAC3 is not obvious to the less technically inclined.

Expensive, but for the sake of marital bliss, it was money well spent!

Thanks! This makes a lot of sense.
BTW, why did you need the HPA4 for switching between digital sources when you have the miniDSP which has a nice looking display?

 

[gfinlays]

My Roon endpoint (RPi 4B) connects to the DAC3 via USB. The mini DSP (2x4 HD, no display) takes the TOSLINK from the TV.

The HPA4 switches between the DAC's balanced output and the MiniDSP's RCA output. The DAC3 runs in calibrated HT mode with a fixed output to the HPA4.

 

[gabrielb]

I see, you are using the entry level miniDSP with analog out and no display.
I was thinking the miniDSP Studio or Flex-Digital with multiple digital IN/OUT, volume control and an LCD display

 

[aedagnino]

I use this:

DROK USB Volume Controller

My setting is different (Roon + JRiver with DIRAC plugin) but I'm pretty sure that it should work, as it's plug and play. I use a Beelink Mini S as the pc.
If you're single source then it's a no brainer. In my case I also have a turntable connected to Roon as a live Radio (you have to stream it through an internet caster/streamer) so I can control everything through that.

 

[gfinlays]

I use this:

DROK USB Volume Controller

My setting is different (Roon + JRiver with DIRAC plugin) but I'm pretty sure that it should work, as it's plug and play. I use a Beelink Mini S as the pc.
If you're single source then it's a no brainer. In my case I also have a turntable connected to Roon as a live Radio (you have to stream it through an internet caster/streamer) so I can control everything through that.

How does that unit work? Does it simply digitally attenuate what's coming in, or does it resample to a higher bit depth before attenuating to preserve dynamic range?

 

[gabrielb]

I use this:

DROK USB Volume Controller

My setting is different (Roon + JRiver with DIRAC plugin) but I'm pretty sure that it should work, as it's plug and play. I use a Beelink Mini S as the pc.
If you're single source then it's a no brainer. In my case I also have a turntable connected to Roon as a live Radio (you have to stream it through an internet caster/streamer) so I can control everything through that.

It seems like a copycat of the old Griffin PowerMate (https://en.wikipedia.org/wiki/Griffin_PowerMate) which is an alternative to the computer volume slider.
I don't think it will effect foobar2000 which is using the USB-DAC with an ASIO driver.

I wonder how hard will it be to write a foobar2000 plugin to use it as an external physical volume knob.
Even better, maybe write a plugin for a wireless knob like the one used by microsoft surface dial (https://www.microsoft.com/en-us/d/surface-dial/925r551sktgn)

Apparently, someone already implement it for roon - https://community.roonlabs.com/t/ro...b-for-roon-with-microsoft-surface-dial/134502

It is also supported by miniDSP SHD serie

SHD + Microsoft Dial

miniDSP is a leading manufacturer of Digital Audio Signal Processors for the HomeTheater, Hifi, headphone and Automotive market. Join our large community of Audiophiles, Engineers and DIYers using our innovative products.

www.minidsp.com

 

[gabrielb]

How does that unit work? Does it simply digitally attenuate what's coming in, or does it resample to a higher bit depth before attenuating to preserve dynamic range?

I don't think it does anything aside from sending increase/decrease volume commands to MS-Windows

 

[Kal Rubinson]

I don't think it does anything aside from sending increase/decrease volume commands to MS-Windows

When using it with JRiver, it should be controlling the 64bit VC operation in JRMC, not any MS-Windows operations.

 

[aedagnino]

When using it with JRiver, it should be controlling the 64bit VC operation in JRMC, not any MS-Windows operations.

Yep, when you have JRiver open it controls the volume, should happen the same in Foobar. However, with JRiver WASAPI as the default audio output for Windows it controls all audio (I have system sounds silenced in any case). It's a digital attenuator as GFinlays says, but with the 64 bit headroom you have it's kind of a moot point. I believe Foobar also has a WASAPI output support you can use? Thus, you can choose the Foobar WASAPI in windows as the default output.

 

[aedagnino]

https://www.foobar2000.org/components/view/foo_out_wasapi
There you have it! I don't use Foobar, but I'm guessing you just specify in Foobar what output you'll be using and with the wasapi component you'd be able to select it in windows sound settings, as per JRiver.

 

[Hear Here]

I'll be unpopular for suggesting this, but you've boxed yourself in by having too many boxes to handle a single source. I'd never consider a PC to handle any audio signal - leave these non-audio things for control only.

Have you home auditioned the AHB1 with your GamuT speakers? That amp is loved by many (it has some nice features such as measured accuracy, low noise, gain selection, good looks, compact design, reasonable price) , but it is particularly speaker dependent. It was drearily dull with my speakers so I auditioned several alternatives before ditching the BM (thankfully the dealer offered a full-value credit note with which I bought a truly great used GamuT amp) and moved on to much more musical satisfaction.

You ask about getting a stand-alone DAC, perhaps with volume control. With modern DAC circuits being the size of a matchbox, have you considered an amp (an integrated) with a built-in DAC? Saves a number of cables too. If you are using your PC for streaming as your single source (no CD or no vinyl), perhaps all you need is an audio-spec streamer / server. Where in the chain (hard drive music store (if used) > streamer > DAC > preamp > power amp) you introduce a cable is a moot point. There's a lot to be said for an all-in-one if well chosen. It's much more cost effective and all components are designed to work well with one another. Or break before the power amp, so a streaming-pre feeding it. These routes reduce the considerable cost of a pile of enclosures and power supplies if they share one - and of course there's a reduction in cables that never improve audio quality, however costly they may be. Food for though, or instantly dismissed? Good luck anyway

 

[aedagnino]

I'll be unpopular for suggesting this, but you've boxed yourself in by having too many boxes to handle a single source. I'd never consider a PC to handle any audio signal - leave these non-audio things for control only.

Have you home auditioned the AHB1 with your GamuT speakers? That amp is loved by many (it has some nice features such as measured accuracy, low noise, gain selection, good looks, compact design, reasonable price) , but it is particularly speaker dependent. It was drearily dull with my speakers so I auditioned several alternatives before ditching the BM (thankfully the dealer offered a full-value credit note with which I bought a truly great used GamuT amp) and moved on to much more musical satisfaction.

You ask about getting a stand-alone DAC, perhaps with volume control. With modern DAC circuits being the size of a matchbox, have you considered an amp (an integrated) with a built-in DAC? Saves a number of cables too. If you are using your PC for streaming as your single source (no CD or no vinyl), perhaps all you need is an audio-spec streamer / server. Where in the chain (hard drive music store (if used) > streamer > DAC > preamp > power amp) you introduce a cable is a moot point. There's a lot to be said for an all-in-one if well chosen. It's much more cost effective and all components are designed to work well with one another. Or break before the power amp, so a streaming-pre feeding it. These routes reduce the considerable cost of a pile of enclosures and power supplies if they share one - and of course there's a reduction in cables that never improve audio quality, however costly they may be. Food for though, or instantly dismissed? Good luck anyway

I agree, it makes you unpopular .
Jokes aside, I see your point. Going my route is more cumbersome and takes some tinkering. It is though in my opinion the most cost-effective way of having a high performance digital based system where you can perform DSP as well as the most future-proof system. I had a miniDSP based system before but I felt that I didn't want to tie myself into one company, plus I wanted to have the ability to upgrade my DIRAC system up to ART when the time came. Plus, didn't want my license to depend on a specific product which I could lose if that went kaput.
I know, I know, it's a variant of the integrated vs separates discussion, but given that our OP already has a PC based system, I thought that the USB Volume Controller is probably the cheapest (by far) option available for him right now, which with just a couple of other downloads and tinkering he could be enjoying as soon as he got the controller in the mail.
I control everything through my Roon Remote though, the knob is just there to control volume as all audio is passed through JRiver and its 64 bit engine.

 

[gfinlays]

Have you home auditioned the AHB1 with your GamuT speakers? That amp is loved by many (it has some nice features such as measured accuracy, low noise, gain selection, good looks, compact design, reasonable price) , but it is particularly speaker dependent. It was drearily dull with my speakers so I auditioned several alternatives before ditching the BM (thankfully the dealer offered a full-value credit note with which I bought a truly great used GamuT amp) and moved on to much more musical satisfaction.

I'd argue that the AHB2 isn't particularly speaker dependant at all. It has no difficulty with extreme loudspeakers that push it into sub 1 ohm EPDR values. The AHB2 lets you hear speakers as they truly sound, not how they sound with an amplifier whose output is electrically compromised by a load it isn't designed to handle.

The AHB2 doesn't sound drearily dull - it is transparent in extremis. It has no sonic signature whatsoever and has the measurements to prove it. As such it is ruthlessly revealing of everything else in the audio chain. If a speaker sounds dull with the AHB2, the speaker sounds dull. It's like shooting a portrait with a 100MP medium format camera with the finest glass. Every line, wrinkle and blemish is there to see in glorious detail. No retoucher's brush to beautify the subject.......

 

[Hear Here]

I'd argue that the AHB2 isn't particularly speaker dependant at all. It has no difficulty with extreme loudspeakers that push it into sub 1 ohm EPDR values. The AHB2 lets you hear speakers as they truly sound, not how they sound with an amplifier whose output is electrically compromised by a load it isn't designed to handle.

The AHB2 doesn't sound drearily dull - it is transparent in extremis. It has no sonic signature whatsoever and has the measurements to prove it. As such it is ruthlessly revealing of everything else in the audio chain. If a speaker sounds dull with the AHB2, the speaker sounds dull. It's like shooting a portrait with a 100MP medium format camera with the finest glass. Every line, wrinkle and blemish is there to see in glorious detail. No retoucher's brush to beautify the subject.......

I wasn't suggesting that the AHB2 has any difficulty with particular speakers, but that it's performance in terms of the musical enjoyment it delivered being speaker dependent. And judging by the reviews from respected sources, there is usually a caveat suggesting just that, despite its generally favourable reviews and excellent lab results.

With my own speakers, that must be just about the least problematic to any amp being 18 ohms and 107 dB, the BM turned out to be drearily dull, compared with the previous amps that I'd been using and compared with some (not all) of the many amps I bought or borrowed subsequently to find a better amp. If, while listening to music that one normally enjoys, the tendency is to reduce the volume, rather than to pep it up - this is the Kiss of Death as far as I'm concerned.

Musak is not what I buy an amplifier for and there was rarely an occasion when I wanted to play favourite music loudly with that particular amp. There were others that were no better, or were worse, but it really disappointed that the BM fell into that group, as my expectations were high after reading a particular forum thread praising it to high heaven. It was then a new product with no worthwhile reviews and I had to buy it unheard from a dealer 400 miles away - I'd been that convinced it would be fantastic - hence my suggestion that the OP tries this amp in his own system before committing.

 

[boxerfan88]

I wrote my own foobar volume controller web app.

If you want to try it out, you can download from here:

Read-only remote control using foo_beefweb API

Read-only remote control using foo_beefweb API

hydrogenaud.io

This may be suitable for your use case #1, and help you temporarily until such time you buy a DAC with volume control.

 

[gabrielb]

I'll be unpopular for suggesting this, but you've boxed yourself in by having too many boxes to handle a single source. I'd never consider a PC to handle any audio signal - leave these non-audio things for control only.

Have you home auditioned the AHB1 with your GamuT speakers? That amp is loved by many (it has some nice features such as measured accuracy, low noise, gain selection, good looks, compact design, reasonable price) , but it is particularly speaker dependent. It was drearily dull with my speakers so I auditioned several alternatives before ditching the BM (thankfully the dealer offered a full-value credit note with which I bought a truly great used GamuT amp) and moved on to much more musical satisfaction.

You ask about getting a stand-alone DAC, perhaps with volume control. With modern DAC circuits being the size of a matchbox, have you considered an amp (an integrated) with a built-in DAC? Saves a number of cables too. If you are using your PC for streaming as your single source (no CD or no vinyl), perhaps all you need is an audio-spec streamer / server. Where in the chain (hard drive music store (if used) > streamer > DAC > preamp > power amp) you introduce a cable is a moot point. There's a lot to be said for an all-in-one if well chosen. It's much more cost effective and all components are designed to work well with one another. Or break before the power amp, so a streaming-pre feeding it. These routes reduce the considerable cost of a pile of enclosures and power supplies if they share one - and of course there's a reduction in cables that never improve audio quality, however costly they may be. Food for though, or instantly dismissed? Good luck anyway

I am too lazy to audition multiple amplifiers driving my heavy floor standing speakers around town.
I had the benchmark dac3b which I liked so adding the ahb2 made sense to me.

At some point in the near future I will get new speakers so it will be much easier to audition speakers with me carrying the relatively small and light ahb2 together with the dac and my tinny nuk music server.
I like the fact that benchmark products are transparent as my foobar server giving me a lot of flexibility in selecting speakers.

 

[gabrielb]

I wrote my own foobar volume controller web app.

If you want to try it out, you can download from here:

Read-only remote control using foo_beefweb API

Read-only remote control using foo_beefweb API

hydrogenaud.io

View attachment 382890


This may be suitable for your use case #1, and help you temporarily until such time you buy a DAC with volume control.

I don't have a problem controlling foobar from my phone - I got foobar controller (https://foobar2000controller.blogspot.com/p/how-to-start.html) installed on my phone in addition to a few old phones used only as foobar remotes.

I was looking for a way to add physical knob volume control to foobar - I assume all of them send some kind of Bluetooth/Wifi packets to the system and should be possible to route the messages to foobar.
It might even be possible to use a smart light switch as a physical controller.
I saw that the Surface Dial has some kind of an API which might be possible to use.

Support the Surface Dial (and other wheel devices) in your Windows app - Windows apps

A step-by-step tutorial for adding support for the Surface Dial (and other wheel devices) to your Windows app.

learn.microsoft.com

Now, I just need to find the time for such a project and to see how annoying windows API can be ...

I just found about the discontinued NUIMO product which seems like a heaven sent (and like all good things was taken too early)

https://www.kickstarter.com/projects/802159142/nuimo-seamless-smart-home-interface

 

[gabrielb]

https://www.foobar2000.org/components/view/foo_out_wasapi
There you have it! I don't use Foobar, but I'm guessing you just specify in Foobar what output you'll be using and with the wasapi component you'd be able to select it in windows sound settings, as per JRiver.

I can change foobar output to use WASAPI, but I rather stay with Benchmark supplied ASIO drivers.

Just to be clear, the device doesn't perform any bit manipulation itself - it is merely an alternative to changing the volume with an attached keyboard (I guess it is mascarding as a keyboard) or did I missed something?
--Edit--
I checked the product spec and indeed it is registering itself as a keyboard and you can even configure which key sequence to send for each operation.
Assuming I leave foobar2000 in focus then all keystrokes will arrive to it so I can configure the gadget to send foobar key binding for vol up/down/mute and next/prev track easily.
Come to think about it, the same could be done with Microsoft surface dial...

I could imagine a bridge device acting as multifunction USB target and initiator- taking the USB audio stream, applying digital attenuation and sending the attenuated data downstream.
You could probably implement the whole thing in a small device embedded in the USB cable like some of the entry level DACs.
It should be powered by USB and can even have a BT receiver to allow controlling it with a remote knob like the surface-dial or something like nuimo (RIP)