MINIDSP Adept ADC & Phono Preamp Review

[rocksteady]

There's anecdotal evidence that a phono preamplifier with good headroom makes LP surface noise seem quieter.

That has certainly been my experience, as I've progressed through several Phono stages over the last the 3 decades. A sobering realisation was that Price didn't necessarily correlate with that progression. The basic conclusion is that one doesn't have to spend Mega bucks to obtain top performance, especially so with MMs, of course...

 

[Soniclife]

There's anecdotal evidence that a phono preamplifier with good headroom makes LP surface noise seem quieter.

Does that apply to stages using adc?

 

[somebodyelse]

Does that apply to stages using adc?

It probably depends which bit is overloading and what its recovery is like. If we ask nicely then some Adept, Puffin and Waxwing users might do some tests so we can see how they react to the same input at different gain levels. I don't know about the Adept, but IIRC the Puffin and Waxwing have indicators to show if you've clipped at input or output so you can adjust gain and processing accordingly.

 

[MaxwellsEq]

Does that apply to stages using adc?

Hopefully they have some amplifier with a bit of gain or attenuation ahead of the ADC. Overloading an ADC is a very bad idea.

 

[Soniclife]

Hopefully they have some amplifier with a bit of gain or attenuation ahead of the ADC. Overloading an ADC is a very bad idea.

I've always heard that, but would love to see a measurement showing what happens, with modern kit. When my DSP phone stage shows clipping its not obvious.

 

[MaxwellsEq]

I've always heard that, but would love to see a measurement showing what happens, with modern kit. When my DSP phone stage shows clipping its not obvious.

It's very easy, if you have an ADC, to demonstrate how bad clipping is. The whole basis of Nyquist sampling assumes peak signals are always below 0 DBFS.

Unlike analogue electronic devices or tape recorders (which have compression or limiting behaviours), overloading an ADC (even a 2025 model) is a mess

 

[Loz]

I’ve not tested my Adept with measurement software, but I’ve ripped perhap a dozen albums to Audacity via the USB connection. I’ve really been happy with its performance via USB and have not noticed any glitches in the waveform (which I review critically for clicks and pops when I digitally “clean” the recording.) It acts like a conventional USB device.

My previous solution for this was Philips GA 212 turntable -> Schitt Mani pre -> Swissonic 24/192 ADC (S/PDIF) -> Hifime S2 digi (S/PDIF to USB). The Swissonic was fixed at 24/192k which would occasionally cause my computer to drop samples and which was unnecessary for my 24/96k Flex 8. The Hifime would tend to randomly throw off 1 bit wide clipped, noise spikes which was disconcerting. I assumed it to be a timing or power supply issue, and they were easily removed as just another click but that took time.

There are no such issues with the Adept. Also, I’ve found the High Pass Filter to be a better solution than attempting to filter out low frequency noise post-recording. Getting the gain set properly for the cartridge took a little experimenting but generally it is set and forget. I compared Turntable -> Mani -> Adept -> USB vs. Turntable -> Adept -> USB and I saw no reason to keep the Mani in the sequence. The Adept phono preamp seems at least as good as the Mani. I have been incredibly pleased with the Adept’s ability render exactly what’s on the vinyl to digital without audibly leaving its own mark and to transfer it via USB for recording.

Could you elaborate on your experimenting to get the correct gain? Were you clipping? I've just got my Adept and have it setup as out of the box ATM, no clipping issues. I'm just wondering how much tinkering may be required to optimise.

Unrelated FYI, I'm in the UK where the cheapest I could get it from a dealer was £399 I think. I got it direct from minidsp delivered for £250. It took 3 days from ordering. I was expecting FedEx to send me a VAT invoice to pay before it was released to be delivered, but it never came. Yay! I'm hoping it doesn't come retroactively. In any case, still much cheaper.

 

[deercreekaudio]

Just a heads up for those that have products such as the MiniDSP and are considering the Adept, the remotes do not have unique codes. For example, turning off the MiniDSP, turns ON the Adept!

The miniDSP ADept infrared remote can be disabled with the procedure below. This is for user convenience when using the ADept with another miniDSP processor.

To disable the remote:

1. Press and hold down the encoder button.
2. Wait for ten seconds until the currently-lit front panel LEDs briefly flash off, then turn on again.
3. Release the encoder button.

From then on, the front LEDs will flash off and on again when the ADept detects a command from the remote, but the command will be ignored.
To enable the remote again, repeat the above procedure.

 

[deercreekaudio]

This is easy to explain.
The $299 is a net price ex works in China, not the USA. This does not include any taxes or customs duties in your country, nor does it include shipping, handling, etc.
If a dealer offers the device in your country, they bear the entire risk for warranty and other claims, as well as all risks and shipping and handling costs.
Of course, a dealer doesn't do this for free.

Otherwise, no one is stopping you from ordering the device directly for this price. However, the entire responsibility then lies with you, and you would have to return it at your own expense for the warranty.

Excerpt from the shipping conditions:
For shipments to the rest of the world:
- Shipping costs advertised on the miniDSP website are for shipping costs only. The customer is responsible for paying all taxes and duties, including country, provincial, government, state and local sales, use, goods and services, value-added, privilege and similar levies/taxes. Please contact your local customs office to learn of your country's import fee structure.
- The customer is responsible for clearing, filling and submitting any document or process required by the destination authority such as custom, shipping carriers.

Import duties from Hong Kong (now classified as China) are constantly changing, with new tariff threats coming and going daily. To accurately research the current import duties you need to know:

• Harmonized Tariff Schedule (HTS) Code: 8519.89.3000
• Country of Origin (COO): Hong Kong

Deer Creek Audio is an authorized US miniDSP ADept dealer.

 

[dziemian]

I wish it had AES/ EBU output

 

[morillon]

I wish it had AES/ EBU output

Do you need to manage a long distance of cabling?

(ps otherwise there is the solution of an active adapter or sut etc spdif to aes...)

 

[dziemian]

I need to cover a distance of 20m to my AES/EBU digital input in OKTO Dac.

 

[morillon]

I need to cover a distance of 20m to my AES/EBU digital input in OKTO Dac.

You're saying that's not a very standard case... ;-)

The idea of active adapters seems like a good option to consider... ;-)

 

[markstein]

That is my understanding as well. Mine outputs an average 4mV, therefore "safe", based on your assessment...

I would assume a headroom of about 20dB on top of your output voltage at 5cm/s to be on the safe side regarding clipping, even with hotter cuts.

 

[dziemian]

You're saying that's not a very standard case... ;-)

The idea of active adapters seems like a good option to consider... ;-)

Hosa CDl-313 is ok?

S/PDIF Coax to AES/EBU - Digital Audio Interface | Hosa Cables

The CDL-313 Digital Audio Interface by Hosa Technology allows simultaneous transfer between S/PDIF coax and AES/EBU digital audio formats.

hosatech.com

 

[morillon]

Hosa CDl-313 is ok?

S/PDIF Coax to AES/EBU - Digital Audio Interface | Hosa Cables

The CDL-313 Digital Audio Interface by Hosa Technology allows simultaneous transfer between S/PDIF coax and AES/EBU digital audio formats.

hosatech.com

In first ..try just... not expensive... like 25 dollars etc actif... from toslink...
if your receiver is good..should be enough.... ;-)

 

[dziemian]

Another minidsp product which ticks some boxes and lacks others and you still end up with extra adapters/ converters. I dont get this spdif output. People who want to digitize theirs LPs would use usb. Audiophiles would probably stick to analog side and those who use studio interfaces still need another converter.

 

[Yorkshire Mouth]

Another minidsp product which ticks some boxes and lacks others and you still end up with extra adapters/ converters. I dont get this spdif output. People who want to digitize theirs LPs would use usb. Home users would probably stick to analog side and pro still need another converter.

I am left scratching my head that some people don’t get it.

There are a lot of digital preamps (and ting) out there with great EQ, room correction, subwoofer/bass management all done in the digital domain, but with poor or poor-ish) ADC stages.

I have a WiiM Ultra. I love the flexibility of the digital processing, but the ADC stage doesn’t measure too well - in many ways it’s the Ultra’s weakest link. This would (potentially) change that.

It’s just something for digital devices with poor ADC stages.

Once you’ve figured that out, it all makes sense.

 

[nothingman]

Another minidsp product which ticks some boxes and lacks others and you still end up with extra adapters/ converters. I dont get this spdif output. People who want to digitize theirs LPs would use usb. Home users would probably stick to analog side and pro still need another converter.

Maybe it’s just my bias, but I’d best most people are using this as a simple digital phono preamp where having both spdif and toslink is common and helpful for managing I/O capacity of the next device in the chain.

Your case of a 20m AES-EBU cable run is not the norm (think of the tiny percentage of users where that’s happening). SPDIF to AES conversion is easy and usually just a matter of single cable with RCA on one end and XLR on the other, but not at your distance. You have to accept that’s extremely rare and adapt accordingly.

 

[Roland68]

Another minidsp product which ticks some boxes and lacks others and you still end up with extra adapters/ converters. I dont get this spdif output. People who want to digitize theirs LPs would use usb. Audiophiles would probably stick to analog side and those who use studio interfaces still need another converter.

However, it doesn't make much sense to make a device €100 more expensive if this feature is of interest to at most 1% of buyers, or less. It would definitely jeopardize the device's success, or the device would have to be at least two to three times more expensive.

If you have DIY skills, you can build a very good SPDIF converter with two ready-made boards for €60, plus a case and power supply, capable of outputting AES/EBU, SPDIF coax, Toslink, and I2S over LVDS (HDMI connector).
For an additional €20-50, you can add a USB input and switch between the inputs.
You can also set up the whole thing as a powerful SRC for an additional €50.