Topping E70 randomly went to MAX volume..

[Trell]

These problems are not exclusive to Chinese DACs
Have a look at these. ADI-2 DACs aren't exactly perfect.
https://forum.rme-audio.de/viewtopic.php?id=31545
https://forum.rme-audio.de/viewtopic.php?id=29667
https://forum.rme-audio.de/viewtopic.php?id=27870
https://forum.rme-audio.de/viewtopic.php?id=29856

Nope, no manufacturer is perfect, but RME do take care of their customers when there are issues.

For the rotary encoder skipping RME did release a firmware update that fixed it, and users seemed to agree. As I recall corrosion could occur and thus giving a bad contact.

 

[Burns]

A DAC is not an amplifier, it's not a preamplifier. Why are you adjusting the volume with the DAC? Your amps don't have a volume control knob? The amplifier unscrewed to 45% of the DAC even with the explosion at 100% is still 45% volume amplification. What are you up to?

 

[Hapo]

Rotel RC-1572 MKII (Black)

Stereo preamplifier with built-in DAC and Bluetooth®

www.crutchfield.com

...this solved the issue for me...

 

[Trell]

A DAC is not an amplifier, it's not a preamplifier. Why are you adjusting the volume with the DAC? Your amps don't have a volume control knob? The amplifier unscrewed to 45% of the DAC even with the explosion at 100% is still 45% volume amplification. What are you up to?

It's really weird using a volume control on a DAC to adjust the volume level. What are manufacturers like RME thinking adding such a nice volume knob on my RME ADI-2 DAC FS!

 

[Roland68]

RME did release a firmware update that reduced/fixed that problem, as I recall, if this is your problem. Fortunately my ADI-2 DAC FS that I bought a couple of years ago never had that problem.

Another issue is with some units of the ADI-DAC FS that uses the ESS DAC IC have a high frequency tone (10 kHz+, if I remember correctly) that can be heard by some when the screen has a certain brightness. There is a simple hardware fix, so you'll have to send it back to RME or one of the distributors.

In any case, RME don't abandon their users to their own devices. All manufacturers have some issues and it's important how they deal with it.

Firmware Update ADI-2 DAC 66 / 47 and ADI-2 Pro 259 / 111 (Page 1) — ADI-2 & 2/4 Pro series, ADI-2 DAC series — RME User Forum

Firmware Update ADI-2 DAC 66 / 47 and ADI-2 Pro 259 / 111 (Page 1) — ADI-2 & 2/4 Pro series, ADI-2 DAC series — RME User Forum —

forum.rme-audio.de

>>>Encoder jumping and direction errors: This firmware includes a new logic unit that intelligently detects and eliminates encoder switching contact errors. In addition, there is a variable filter with levels 1 to 5. Default is 1, which is largely similar in feel to the previously used filter. Higher values lead to an attenuation of very fast changes. Strongly jumping or backward running encoders can in most cases be used normally again with the setting 3. Very fast, short rotations can be replaced by medium-fast rotations after a short period of familiarization.<<<

With the update, RME only fixes a control problem with the encoder/knob used. This is about the rapid change in volume with fast rotary movements, or incorrect interpretation of the position of the encoder/rotary control.

This has nothing at all to do with the problem of topping or other DACs, where the volume is only reduced via the DSP functions of the DAC chip.

 

[Deleted member 58722]

Is it not best to get a DAC with volume cvontrol on the analoge output? And turn it to zero when finished with?
As is good practice, when I have finished listening to my main system, both pre-amp and power amp are set zero before
turning off, and turned on before setting volume. As is my headphone DAC.
( Zero being fully off )

 

[Trell]

This has nothing at all to do with the problem of topping or other DACs, where the volume is only reduced via the DSP functions of the DAC chip.

I know as I was replying to his post about his RME.

 

[Smoey22]

I am worried that this could happen in my setup, especially with somebody else in the household using it and not knowing instinctively how to turn things off. However, I have never experienced my DAC doing a unsolicited full volume reset, even when intentionally switching between variable and fixed pre mode (although it states to turn down the amp volume when changing this setting).

Today I am running a DAC (SMSL DO300) directly (balanced) to an amplifier (Hypex NC252MP).
The DAC is usually fed by USB (PC) or OPT (TV), volume controlled by the DAC.

Running accidentally 250 W through my speakers yields theoretically about 115 dB, that gives less than 30 seconds of exposure before permanent hearing impairment occurs (ref. NIOSH, CDC, OSHA). Adding some room gain on top results in a not so favorable situation to be in.

Could installing a passive preamplifier between the DAC and the amplifier be a reasonable safety precaution, for example this Passive Preamplifier converter RCA to XLR / XLR to RCA Silver from Audiophonics? Would I introduce any significant sound quality degradation in my chain by implementing this equipment using balanced connections?

 

[Deleted member 48726]

I am worried that this could happen in my setup, especially with somebody else in the household using it and not knowing instinctively how to turn things off. However, I have never experienced my DAC doing a unsolicited full volume reset, even when intentionally switching between variable and fixed pre mode (although it states to turn down the amp volume when changing this setting).

Today I am running a DAC (SMSL DO300) directly (balanced) to an amplifier (Hypex NC252MP).
The DAC is usually fed by USB (PC) or OPT (TV), volume controlled by the DAC.

Running accidentally 250 W through my speakers yields theoretically about 115 dB, that gives less than 30 seconds of exposure before permanent hearing impairment occurs (ref. NIOSH, CDC, OSHA). Adding some room gain on top results in a not so favorable situation to be in.

Could installing a passive preamplifier between the DAC and the amplifier be a reasonable safety precaution, for example this Passive Preamplifier converter RCA to XLR / XLR to RCA Silver from Audiophonics? Would I introduce any significant sound quality degradation in my chain by implementing this equipment using balanced connections?

There are tons of threads discussing passive volume control. Try the search function.

 

[Mat]

A DAC is not an amplifier, it's not a preamplifier. Why are you adjusting the volume with the DAC?

DACs are pre-amplifiers.

 

[MaxwellsEq]

DACs are pre-amplifiers.

DAC stands for Digital-to-Analogue-Converter. There's nothing in the definition that suggests it's a preamplifier.

If you mean it precedes an amplifier in the chain, that's true, but that's not the definition of preamplifier. A preamplifier usually has analogue inputs at line level and phono level and outputs at line level; it has switching between inputs and level adjustment. It sometimes has tone controls.

 

[Mat]

DAC stands for Digital-to-Analogue-Converter. There's nothing in the definition that suggests it's a preamplifier.

If you mean it precedes an amplifier in the chain, that's true, but that's not the definition of preamplifier. A preamplifier usually has analogue inputs at line level and phono level and outputs at line level; it has switching between inputs and level adjustment. It sometimes has tone controls.

You're being mindnumbingly pedantic.

There's more to a "DAC" unit than just the DAC chip itself. In the case of this unit, it has a pre-amp stage integrated into it, as many DACs do.

 

[Burns]

You're being mindnumbingly pedantic.

There's more to a "DAC" unit than just the DAC chip itself. In the case of this unit, it has a pre-amp stage integrated into it, as many DACs do.

The car has a thermometer, then is it a self-propelled thermometer?
Still don't understand ? Watch Ifi DAC signature one!

 

[Roland68]

DACs are pre-amplifiers.

DACs aren't preamps, and they don't become preamps just because someone wants them to be.
A preamplifier works in the small-signal range, which is also where the volume control is located. This is a very big difference to the DACs discussed here.

There are a few exceptions where an analog preamp has been integrated into a DAC, but these are only a handful of devices.

 

[Mat]

the car has a thermometer, then is it a self-propelled thermometer?

Dumbest thing I've read all day, and I've been on twitter.

DACs aren't preamps, and they don't become preamps just because someone wants them to be.

There are a few exceptions where an analog preamp has been integrated into a DAC, but these are only a handful of devices.

Oh so the goalposts are now about analog pre-amps? Because its clear that this unit has a digital pre-amp section.

DACs can be pre-amps, they don't stop being pre-amps just because someone wants them to not be.

 

[Sokel]

Dumbest thing I've read all day, and I've been on twitter.



Oh so the goalposts are now about analog pre-amps? Because its clear that this unit has a digital pre-amp section.

DACs can be pre-amps, they don't stop being pre-amps just because someone wants them to not be.

View attachment 281613

Can you point me to the positive gain of the particular pre-amp?

 

[Burns]

Dumbest thing I've read all day, and I've been on twitter.



Oh so the goalposts are now about analog pre-amps? Because its clear that this unit has a digital pre-amp section.

DACs can be pre-amps, they don't stop being pre-amps just because someone wants them to not be.

View attachment 281613

and on Twitter they didn't explain what "+ preamplifier mode" means?

 

[MaxwellsEq]

Dumbest thing I've read all day, and I've been on twitter.



Oh so the goalposts are now about analog pre-amps? Because its clear that this unit has a digital pre-amp section.

DACs can be pre-amps, they don't stop being pre-amps just because someone wants them to not be.

View attachment 281613

They can call it whatever they want, but it's not a preamplifier. I bought my first preamplifier several years before CD, it had an MM phono input, line level connections for tape in and out and tuner and aux in. It had POSITIVE GAIN, as well as attenuation and output at line level into a separate power amp. The gain and buffers were all built with transistors with no op-amps or chips.

The oldest preamplifier I've worked on was all tubes from the 60s.

What you've shown there is not a preamplifier.

 

[Roland68]

Oh so the goalposts are now about analog pre-amps? Because its clear that this unit has a digital pre-amp section.

DACs can be pre-amps, they don't stop being pre-amps just because someone wants them to not be.

View attachment 281613

It is quite clear that this DAC does not have a digital preamp section. Topping didn't claim that either, they only talk about a preamplifier function.
He also has no volume control in the true sense, but only a dangerous volume reduction.

This manufacturer uses a DSP function in the DAC chip to reduce the volume. This happens digitally in the DAC chip, before the D/A conversion. This DSP function is controlled via registers and is set to 0dB on start-up, i.e. full volume.
Guess where this volume reduction stands for an error, malfunction, reset, etc.?
The users who have experienced the problem can surely tell you that. Otherwise this thread wouldn't even exist.

The bad thing is that such posts suggest to inexperienced users that it is safe to operate power amplifiers on DACs by using an alleged "preamp function".
Do you take responsibility in the event of damage? Do you compensate these users for the damage they caused?

- A preamp function is not a preamp section, especially if there are no components for it.
- A volume reduction via the DSP functionality of the DAC chip is not a volume control.
- A conventional electronically controlled volume control, whether analogue or digital, always starts at the lowest volume and returns to it in the event of an error.

If the difference between a real volume control (starting point lowest volume) and the volume reduction via the DSP functionality of the DAC chip (starting point full volume) is not completely clear to someone, their power amplifiers should never be operated directly on this or another DAC.

 

[Joel G]

I am worried that this could happen in my setup, especially with somebody else in the household using it and not knowing instinctively how to turn things off. However, I have never experienced my DAC doing a unsolicited full volume reset, even when intentionally switching between variable and fixed pre mode (although it states to turn down the amp volume when changing this setting).

Today I am running a DAC (SMSL DO300) directly (balanced) to an amplifier (Hypex NC252MP).
The DAC is usually fed by USB (PC) or OPT (TV), volume controlled by the DAC.

Running accidentally 250 W through my speakers yields theoretically about 115 dB, that gives less than 30 seconds of exposure before permanent hearing impairment occurs (ref. NIOSH, CDC, OSHA). Adding some room gain on top results in a not so favorable situation to be in.

Could installing a passive preamplifier between the DAC and the amplifier be a reasonable safety precaution, for example this Passive Preamplifier converter RCA to XLR / XLR to RCA Silver from Audiophonics? Would I introduce any significant sound quality degradation in my chain by implementing this equipment using balanced connections?

Hi @Smoey22 , I have bought exactly that passive preamp when I bought my Purifi power amp (no much budget left). It worked fine with a Topping E30 and with a Schiit Modi+ which both have unbalanced outputs, and then from the passive preamp to the power amp with unbalanced too. I tried then swapping the connection between the passive preamp and power amp with balanced, but I felt sound got more sibilant or harsh on the high frequencies, not sure if it was just placebo or if there is a real issue trying to convert unbalanced to balanced with the little passive preamp. I wish I had a balanced source to tell you if xlr in and out would work as good as rca-rca in and out. On a side note, nothing to do with functionality, the small transparent drop-like rubber feet are glued as my 4 year old daughter would have done, luckily this is not visible on a daily basis