(Advice, please) Balanced DAC/Preamp with Safe Volume Control – Preventing Sudden Volume Spikes

[Toni71]

Dear members,

For the time being, I'm looking for a good DAC/preamp with a physical volume knob, remote would be nice. I currently use a Topping DX3 Pro+ (unbalanced), which does have volume control, but I’m hesitant to rely on it as a preamp.

My speakers are KEF Reference 5 Meta, a serious investment (let’s just say it involved selling a kidney ) and I’ve read horror stories about digital volume controls failing or resetting, potentially blowing tweeters. Since my technical background isn’t strong (I studied law), I’m erring on the side of caution.

Would it be wiser to invest in a separate preamp? Ideally, I’d like something with (real?) balanced outputs and a good analog volume control.

Any recommendations would be greatly appreciated!

( I don't need an AV-receiver or processor).

 

[Roland68]

Dear members,

For the time being, I'm looking for a good DAC/preamp with a physical volume knob, remote would be nice. I currently use a Topping DX3 Pro+ (unbalanced), which does have volume control, but I’m hesitant to rely on it as a preamp.

My speakers are KEF Reference 5 Meta, a serious investment (let’s just say it involved selling a kidney ) and I’ve read horror stories about digital volume controls failing or resetting, potentially blowing tweeters. Since my technical background isn’t strong (I studied law), I’m erring on the side of caution.

Would it be wiser to invest in a separate preamp? Ideally, I’d like something with (real?) balanced outputs and a good analog volume control.

Any recommendations would be greatly appreciated!

( I don't need an AV-receiver or processor).

Personally, I would never use a DAC's volume control unless it's independent of the DAC chip. The problem with volume control via the DAC chip is that the default setting in the DAC chip is always 0 dB, i.e., full volume. It should be clear what can happen if something goes wrong.

A budget would be helpful.
Most DACs with independent volume controls are quite expensive, e.g., RME ADI-2 devices or Topping DX9.
Separate devices are cheaper, e.g., Topping L70 with E70, E70 Velvet, or D50 III, and also more flexible.
An inexpensive and good preamplifier would be the Fosi P4.

For a recommendation, the amplifier used would also be useful.

 

[Toni71]

Thank you, Roland.

'Personally, I would never use a DAC's volume control unless it's independent of the DAC chip. The problem with volume control via the DAC chip is that the default setting in the DAC chip is always 0 dB, i.e., full volume. It should be clear what can happen if something goes wrong.'

Exactly this. I won’t go down that path. The DX3Pro+ is dedicated to headphones in my setup.

Budget: The price of the Topping DX9 or the RME ADI-2 is within my range, that's roughly my budget. I’ll look into both options in more detail. There was a mention on the forum that the output impedance of the Topping L70 is too low, which might not be ideal for use as a preamp. Is this better on the DX9?

Power amp: Rotel RB-1582 MKII. I want balanced connections, it helps minimize issues with the power circuit here (HTPC setup). But that’s a different story.

 

[sergeauckland]

The only really safe way to avoid the 0dB problem is to have a physical pot as a volume control. Then, no amount of software glitches will ever cause full volume output. Even just a remote volume control using a motorised pot could theoretically end up at 100%.

Although I've never had the problem in over 20 years, even a digitally controlled analogue volume control as I have could theoretically go 100%.

S.

 

[Roland68]

The only really safe way to avoid the 0dB problem is to have a physical pot as a volume control. Then, no amount of software glitches will ever cause full volume output. Even just a remote volume control using a motorised pot could theoretically end up at 100%.

Although I've never had the problem in over 20 years, even a digitally controlled analogue volume control as I have could theoretically go 100%.

S.

Almost every AVR has digitally controlled analog volume controls. I've never heard of this problem with RME either, but they don't use the DAC chip either; they have their own digital volume control.

In addition, the initial setting isn't 0 dB like with DAC chips, but rather the lowest volume.

Human error (e.g., putting your butt on the remote, children, animals, etc.) is difficult to rule out.

 

[Roland68]

Thank you, Roland.

'Personally, I would never use a DAC's volume control unless it's independent of the DAC chip. The problem with volume control via the DAC chip is that the default setting in the DAC chip is always 0 dB, i.e., full volume. It should be clear what can happen if something goes wrong.'

Exactly this. I won’t go down that path. The DX3Pro+ is dedicated to headphones in my setup.

Budget: The price of the Topping DX9 or the RME ADI-2 is within my range, that's roughly my budget. I’ll look into both options in more detail. There was a mention on the forum that the output impedance of the Topping L70 is too low, which might not be ideal for use as a preamp. Is this better on the DX9?

Power amp: Rotel RB-1582 MKII. I want balanced connections, it helps minimize issues with the power circuit here (HTPC setup). But that’s a different story.

Yes, it has a very low output impedance, 20 ohms RCA and 40 ohms XLR. That's a good thing, because it can drive absolutely anything perfectly. One of the reasons I bought the L70 is because it can handle any power amp. I've also used it with a variety of power amps without any problems.
The Rotel RB-1582 MKII should drive perfectly with it.

Are you perhaps confusing that with the low input impedance of 2 kOhms? Together with a Topping DAC, you get a ratio of 20:1, also perfect.

With the relay-based volume control, you have perfect channel balance, as well as very little interference with the signal. The L70 is also very transparent, both as a preamp and as a high-performance amplifier.

I ordered it just out of curiosity to test it. But it ultimately won out over preamps that were many times more expensive, and the Topping Pre90 has been on my shelf ever since. A great device, and not just in terms of price/performance.

 

[aikofan]

A couple of years ago, after my MiniDSP Flex assaulted me with full blast noise several times (thankfully after one of their major firmware updates, this hasn't happened again), I bought a DACT clone stepped attenuator from a Chinese seller for around $50 and added it inline between my Flex and my amp.

With my Flex at full volume playing classical music, I slowly turned up the volume pot on the attenuator to the maximum level that I would ever use. I also adjusted my sub's onboard level control to match, both by ear and also with the help of a REW sweep measurement.

Now with this setup, I can continue to use my Flex remote volume control for convenience, but with the reassurance that even if I have another unexpected 0dB blast, the volume might still be loud but won't damage my eardrums or downstream gear.

 

[Esque]

A couple of years ago, after my MiniDSP Flex assaulted me with full blast noise several times (thankfully after one of their major firmware updates, this hasn't happened again), I bought a DACT clone stepped attenuator from a Chinese seller for around $50 and added it inline between my Flex and my amp.

With my Flex at full volume playing classical music, I slowly turned up the volume pot on the attenuator to the maximum level that I would ever use. I also adjusted my sub's onboard level control to match, both by ear and also with the help of a REW sweep measurement.

Now with this setup, I can continue to use my Flex remote volume control for convenience, but with the reassurance that even if I have another unexpected 0dB blast, the volume might still be loud but won't damage my eardrums or downstream gear.

Sounds like a great fail save, would you mind sharing a link to the product?

 

[aikofan]

Sounds like a great fail save, would you mind sharing a link to the product?

Unfortunately, the eBay product listing no longer exists. It was the one linked in this post, so you can see the poster and description there. https://audiosciencereview.com/foru...mp-with-stepped-attenuator.43381/post-1536779

There are other listings on eBay for passive preamps, some that use the same housing, but I'm not seeing many DACT clones, except as parts. Many of the current listings seem to be using Alps clones.

 

[Toni71]

After some thought, I've ordered a Topping DX5 2 and will await the Fosi ZP3; I believe this combination should fulfill my preamp needs.

 

[rdaow]

After some thought, I've ordered a Topping DX5 2 and will await the Fosi ZP3; I believe this combination should fulfill my preamp needs.

But the ZP3 does not have a "physical volume knob", so it does not meet your requirement "Preventing Sudden Volume Spikes". I'm asking because I'm kind of looking for the same thing, so far was looking at Schiit Saga 2F.

 

[Toni71]

The big orange knob is not a volume control? Is that incorrect information or am I misunderstanding something? Your insight is greatly appreciated.

The Kara could be a solution, but in the EU it's not really a bargain, the Fosi is. And for much less, I could even include a DX5 II in the setup.
The Kara costs nearly €1000 in the Netherlands, and I’d still be missing a balanced DAC.

The RME is not an option. I have analog sources and the Topping pre is more expensive for the same usage.

Post edit: I mean the Kara Preamp.

 

[Roland68]

But the ZP3 does not have a "physical volume knob", so it does not meet your requirement "Preventing Sudden Volume Spikes". I'm asking because I'm kind of looking for the same thing, so far was looking at Schiit Saga 2F.

You're probably confusing the ZP3 with another device. It's a classic preamplifier with analog small-signal technology and analog volume control.

 

[rdaow]

Based on what I read here https://www.audiosciencereview.com/...fier-should-be-like.47481/page-9#post-2299715 I have the impression it's not a physical volume control.
EDIT: By "physical" I mean that it has a start and an end and cannot be changed by software, therefore can be used to set an upper limit on the volume.

> The Saga costs nearly €1000 in the Netherlands, and I’d still be missing a balanced DAC.
I can see it for 399 EUR in schiit-europe.com.

 

[Toni71]

Ahem, sorry, I meant the Kara in my post. The Saga doesn’t have a balanced input. If you don’t need that, it’s definitely an option as a preamp.

The 'free' spin from the volume knob from the ZP3 is again something to think about. Thank you.

 

[rdaow]

I don't need balanced input at the moment (Wiim Ultra is my source), I don't even need the preamp I'm currently running this one but was thinking to upgrade.

 

[Toni71]

Why an upgrade if this works for you?

 

[AaronJ]

A couple of years ago, after my MiniDSP Flex assaulted me with full blast noise several times (thankfully after one of their major firmware updates, this hasn't happened again), I bought a DACT clone stepped attenuator from a Chinese seller for around $50 and added it inline between my Flex and my amp.

With my Flex at full volume playing classical music, I slowly turned up the volume pot on the attenuator to the maximum level that I would ever use. I also adjusted my sub's onboard level control to match, both by ear and also with the help of a REW sweep measurement.

Now with this setup, I can continue to use my Flex remote volume control for convenience, but with the reassurance that even if I have another unexpected 0dB blast, the volume might still be loud but won't damage my eardrums or downstream gear.

This is what I do as well. Slightly different arrangement since I have the Flex in the pre-out/main-in loop but there is an analog pot after the Flex to protect the speakers. I’ve had my Flex go to full volume after running a Dirac Live calibration. Not sure if it was my fault or software’s fault but the volume pot protected the speakers from potential damage. I use the Flex for volume control.

 

[rdaow]

Why an upgrade if this works for you?

This site is an upgrade trap

 

[Esque]

I don't need balanced input at the moment (Wiim Ultra is my source), I don't even need the preamp I'm currently running this one but was thinking to upgrade.

With the Wiim Ultra and its volume limit + output voltage setting. Do you still find It a risk to run it directly into a power amp?