Presonus Quantum Interfaces

[Larry Shelby]

https://www.proaudiostar.com/2024/introducing-presonus-quantum-es-and-hd-interfaces-pure-recording-excellence.html

 

[Soundwise]

https://www.presonus.com/en-US/quantum.html

[ALC]

Supposed to be low latency.  Would like to get actual numbers from RTL Utility.

[Heath Row]

3 hours ago, ALC said:

Supposed to be low latency.  Would like to get actual numbers from RTL Utility.

With the Quantum HD, the signal arrives before it's sent, so the actual numbers are negative. ?

[TheSteven]

5 hours ago, ALC said:

Supposed to be low latency.  Would like to get actual numbers from RTL Utility.

this has been previously discussed & documented... How about 1.6ms?

These stats were from the previous model, not sure what the current model's stats are.

or "At 1ms total round-trip latency, Quantum makes software based monitoring effectively on-par with hardware."
Here's the post to go with that quote (it's at the bottom of that post) but read all of page 3 on that thread to get the proper context.
It mentions that your computer must have the proper components such as having a properly spec'ed thunderbolt 3 port to get that kind of RTL.

The quoted articles were from 2020 and there may be other models or brands that can now get similar latency.
I haven't been following this area since I bought a used Quantum 2 and I'm happy with it, at the moment I see no need to get something else.

Edited May 9 by TheSteven

[Soundwise]

RTL numbers don't mean much unless they come with rock solid performance. E.g., on my laptop theoretically I can get 5.3ms of RTL, however, it's completely unusable.  9.8ms is where the usable range starts in my case. Still, it's not much, as it feels like being 9ft (3m) away from cabinet or monitors. 1ms would be much closer to using in-ear monitors than actual on-stage live band experience.

[ALC]

4 hours ago, TheSteven said:

These stats were from the previous model, not sure what the current model's stats are.

or At 1ms total round-trip latency, Quantum makes software based monitoring effectively on-par with hardware."
Here's the post to go with that quote (it's at the bottom of that post) but read all of page 3 on that thread to get the proper context.
It mentions that your computer must have the proper components such as having a properly spec'ed thunderbolt 3 port to get that kind of RTL.

The new products are using USB-C, and not TB3 (though TB3 uses a USB-C connector), so I don't expect the results to be necessarily identical.

[eaglepass]

To the best of my knowledge the new Quantum HD are USB 2 protocol interfaces while the older models were Thunderbolt.

It will be interesting to see real world latency results with the Quantum HD.

[Larry Shelby]

32 minutes ago, eaglepass said:

To the best of my knowledge the new Quantum HD are USB 2 protocol interfaces while the older models were Thunderbolt.

It will be interesting to see real world latency results with the Quantum HD.

These are  USB-C and Bus-Powered for desktop ones...and the HD are still USB-C

Edited May 9 by cclarry

[eaglepass]

Understood. The connectors are USB C but I believe the actual USB version is USB 2.0 . At least according to Sweetwater. I could find no reference confirming the protocol in any of the Presonus documentation released so far.

[Larry Shelby]

15 minutes ago, eaglepass said:

Understood. The connectors are USB C but I believe the actual USB version is USB 2.0 . At least according to Sweetwater. I could find no reference confirming the protocol in any of the Presonus documentation released so far.

This appears to be correct.  While it is using a USB-C Connector it's still using the USB 2.0 protocol

[Soundwise]

Not your next RTL champion, then. OK.

[TheSteven]

1 hour ago, cclarry said:

This appears to be correct.  While it is using a USB-C Connector it's still using the USB 2.0 protocol

I tried to find the USB-C spec on their devices and failed, other than verifying that they are indeed not Thunderbolt ports.
If they are indeed USB 2.0 that is disappointing as Presonus states on their web page What is USB-C™?
"It should be noted that the default protocol for USB-C™ ports on many Windows computers is USB 3.1"

Edited May 9 by TheSteven

[Moon OverSea]

1 hour ago, cclarry said:

This appears to be correct.  While it is using a USB-C Connector it's still using the USB 2.0 protocol

Yeah, most of the USB interfaces are using USB 2.0 to meet the requirements of all the computers(whatever new or old). The speed should be enough for the 48K 24bits(Daw's setting).

Edited May 9 by Moon OverSea

[Jim Roseberry]

The OG Presonus Quantum series (connected via Thunderbolt) are able to achieve 1ms total round-trip latency.

96k using a 32-sample ASIO buffer size

That won't be the case with any USB unit.

 

If you've got a fast well-configured machine (13900k, 14900k, 7950x):

• You can run ToneX (similar to Kemper but a plugin) at 1ms total round-trip latency
• You can run advanced sample libraries like The Grandeur at sub 1ms playback latency

 

[Technostica]

4 hours ago, TheSteven said:

I tried to find the USB-C spec on their devices and failed, other than verifying that they are indeed not Thunderbolt ports.
If they are indeed USB 2.0 that is disappointing as Presonus states on their web page What is USB-C™?
"It should be noted that the default protocol for USB-C™ ports on many Windows computers is USB 3.1"

From what I have read, most USB AI's are 2.0 because they use third party USB controllers and the manufacturers of those haven't seen the need to upgrade to 3.0.
Which begs the question, what do RME use?

[Starship Krupa]

8 hours ago, eaglepass said:

To the best of my knowledge the new Quantum HD are USB 2 protocol interfaces while the older models were Thunderbolt.

I find this a very interesting development.

I thought Thunderbolt interfaces were the future, due to performance.

I wonder what's behind this shift. I think it's true that there are still many desktop/tower computers that have no Thunderbolt port (yet even my 2017 Dell notebook has a full Thunderbolt port), but there are precious few that don't have USB 3 ports.

Does the difference between USB 2 and USB 3 really not make a difference from a latency standpoint?

I'm still a Firewire guy, was planning on leapfrogging USB2 and going straight to Thunderbolt when the time came.

[TheSteven]

1 hour ago, Technostica said:

From what I have read, most USB AI's are 2.0 because they use third party USB controllers and the manufacturers of those haven't seen the need to upgrade to 3.0.

Yes they probably use 3rd party chips, I think most computer and device manufacturers buy them in bulk. 
But I don't know if the USB-A chips can support USB-C as the interface was entirely redesigned...
https://connectorsupplier.com/usb-type-c-what-you-need-to-know/

• USB-C has bi-direction, rotational-symmetrical (no top/bottom) connections
• USB-C supports higher power delivery (up to 100W) and bidirectional power flow, making it suitable for charging laptops and other high-power devices.
• USB-C can have better data rates which can drive high-resolution monitors

There's a crapload of internal wiring & connections in a USB cable and most manufacturers do not support all features (use all connections) or support the USB 3.1 or 3.2 data speeds which is why you have to be careful buying USB-C cables.
 

 

[Starship Krupa]

22 hours ago, TheSteven said:

I don't know if the USB-A chips can support USB-C as the interface was entirely redesigned

There are no such things as "USB-A chips."

There are USB-A, USB-B, and USB-C connectors.

There are USB 1, USB 2, USB 3 and USB 4 protocols.

I know it's confusing as hell. I was baffled by the whole thing until I bought a nice Dell laptop that had a full Thunderbolt port on it and sat down and read all the Wikipedia articles and crap.

The way to remember USB specs is letters are for connectors and numbers are for protocols.

The US-A connector is still the most common USB socket/plug, it's the wide flat one. They're plentiful on the front and rear of tower computers and on the sides of laptops. USB-A cables usually have a USB-B, C, or one of Apple's proprietary ones like lightning on the other end.

USB-B has common variants like the Micro, which used to be the most common for Android devices (might still be). The full-size USB B connector is most commonly used for large stationary peripherals like printers and scanners. It's usually only used on the peripheral side, with the other end of the cable being USB A.

USB-C is the small symmetrical oval one. A USB-C cable can have either a USB-A or USB-C on the other end.

Now for the protocols.

USB 1 was the first and slowest. I don't know of any audio interfaces that used it, but I wasn't doing digital audio work during that time. I think when it was around, it was more common for audio interfaces to use Firewire. There may have been some MIDI-only USB 1 devices.

USB 2 cranked the speed up to the point where it could handle data fast enough for low-latency audio. USB 2's speed and ease of use kinda killed Firewire.

USB 3 made it even faster. I have not heard of any audio interfaces that use USB 3, maybe because USB 2 was fast enough. USB 3 also introduced SuperSpeed, which is indicated by a blue plastic "tongue" in the USB A jacks.

Okay, here's where things get confusing.

USB 2 can travel via USB A, B, or C connectors. I have a PreSonus Studio 2|4 interface that is USB 2, and has a USB C jack.

USB 3 can travel via USB A or C connectors. The only USB 3 peripherals that I've ever seen are external drives. The fast data transfer is good for that. If anyone knows of a USB 3 audio interface, I'd like to hear about it.

You can plug a USB 2 device into a USB 3 port and it will automatically fall back to USB 2 speeds.

With me so far?

Now we have Thunderbolt, which I think is where a lot of the current confusion comes from.

Thunderbolt is a specification for a type of port. Both physically and electrically. Physically, it uses a USB C connector.

Thunderbolt has gone through versions 1,2, and 3, but the first 2 were used chiefly in Apple products. We're only concerned with Thunderbolt 3, which is where we are now, and it was developed by Intel and released as royalty-free in 2019, at which point other manufacturers like AMD jumped on it.

If your system has a full Thunderbolt 3 port, which my laptop does, it will be a USB C jack marked with a lightning bolt ⚡. If it has that lightning bolt symbol, it means that you can connect Thunderbolt devices, USB 2 and 3 devices, PCIe devices, and video displays. If it's on a laptop, you can also charge the laptop using the Thunderbolt port.

(Not all Thunderbolt ports supply video, it depends on whether the computer supplies it. I think Apple systems and Windows laptops are more likely to supply a video signal via Thunderbolt)

So for instance, at my house, when I want to plug the Studio 2|4 into the laptop, I use a USB C-to-USB C cable and plug it into the Thunderbolt⚡ port and the smarts in the port know to connect via USB 2.

(I can also connect a port extender that has an HDMI jack, audio jacks, and USB A ports carrying USB 3. Right now, the laptop is charging through its Thunderbolt ⚡ port.)

When I want to use the Studio 2|4 on my main tower computer, I use a USB C-to-USB A cable and plug it into either a USB 3 port or a USB 2 port. Doesn't make any difference. It will only run at USB 2 speed because the Studio 2|4 is a USB 2 peripheral.

There is not yet a production USB protocol that will only work over a USB C connection. USB 4 has been released, and it will be USB C-only AND encompass everything that Thunderbolt 3 now has. Many current systems feature USB4 ports, but according to someone whom I trust to be in the know, there are no audio USB4 audio interfaces.

I hope this helps.

Edited May 10 by Starship Krupa
correction regarding USB4 from Jim Roseberry

[kitekrazy]

17 hours ago, Starship Krupa said:

I find this a very interesting development.

I thought Thunderbolt interfaces were the future, due to performance.

I wonder what's behind this shift. I think it's true that there are still many desktop/tower computers that have no Thunderbolt port (yet even my 2017 Dell notebook has a full Thunderbolt port), but there are precious few that don't have USB 3 ports.

Does the difference between USB 2 and USB 3 really not make a difference from a latency standpoint?

I'm still a Firewire guy, was planning on leapfrogging USB2 and going straight to Thunderbolt when the time came.

I was thinking maybe it's not mature on a Windows PC compared to Apple.  Plus it doesn't seem to be priced for the average consumer.