USB interface recommendation needed to digitize open reel tapes

[CtheArgie]

Hello everyone. I need your assistance. I have an old and well kept ReVox B-77 two track open reel recorder. I have a few tapes recorded at 7.5 ips that are very valuable to me. They are of a live band where I sang. Not very good, but it is the only record existing of this. There are other also unique recordings on tape.

I would like to digitize them and planning to use garageband in my Mac as I don't think the quality of the recording requires anything better than the 24/44.1 that the software allows.

I would like to have a "transparent enough" USB driven ADC to convert the signal for the Mac. It MAY be used also if I ever decide to digitize vinyl by connecting as phono preamp to it. Again, SOTA fidelity is not required as vinyl is the miming factor. Lastly, I will use it for a Neumann MA1 EQ for my 750/310 monitors.

I don't think I need a RME Babyface or something so high quality, but something that will get limited use and has sufficient ADC transparency.

Many of you have enormous experience with this and will probably help me. Budget is clearly much less than a babyface. It will be probably defined by the degree of transparency needed for my tasks. Thanks!

 

[ZolaIII]

Read carefully about limitations and software/requirements hire and elsewhere!

E1DA Cosmos ADC

@IVX kindly sent me a sample of the new Cosmos ADC to try out. Here are my impressions of it so far. The Cosmos is housed in a compact metal case with rubber feet, USB Type C connector on one and dual XLR inputs on the other. Power is over USB only. Beside the USB connector is small LED that...

www.audiosciencereview.com

 

[staticV3]

Software limitations: none really on macOS. The Cosmos ADC is plug and play there.

Hardware limitations:
-highest gain clips at 1.7Vrms. Preamplification may be required depending on signal amplitude.
-low input impedance. 1.7Vrms gain has just 640Ω. Increases to 3.48kΩ at 10Vrms gain. Your signal source must be able to work with these impedances.

Before you ask: Yes, the Cosmos ADC's XLR ports can be used for both single-ended sources and balanced ones. Here's what an RCA to XLR adapter would look like for example:

Note that Shield and Cold must be tied together at the RCA end, not at the XLR end.

 

[DVDdoug]

There are lots of good USB audio interfaces with switchable mic/line inputs starting at around $100 USD. Most have combination XLR/TS/TRS input jacks so you'll need the correct adapter/cable.

Lots of people are happy with the much cheaper Behringer UCA202, but it doesn't have a recording-level control and I think it's 16-bits. (But, 16-bits has more dynamic range than analog tape.)


...Note that digital recording levels are not critical as long as you avoid clipping. You can boost (or normalize/maximize) digitally after recording. You probably remember that with tape you wanted a "hot" signal to overcome tape noise but with digital you have a lot more dynamic range and no tape noise. Also, tape is more forgiving if you go occasionally "into the red" where it starts to soft-clip. The analog-to-digital converter is limited to 0dB and it will hard-clip if you "try" to go over.

 

[CtheArgie]

Thanks! I have to say that the E1DA discussion was (is) way over many head!
I know that I'l have to make a few test transfers before I find the right level. I also know I will need a RCA-TS adapter. My Revox has only unbalanced connections.
I did use a little garagaband with a Lyra to record my wife's voice part for a "remote" master chorale group. We shall see with this projects!
I was originally thinking I would need a Focusrite Clarett or something around $500 but I guess much less is sufficient given the inherent quality of tape (and vinyl).

 

[JaccoW]

I plan to record from and to an Akai GX-635D reel to reel when it comes back from an overhaul so I'm curious to see what you're going for. From what I can tell most of the cheaper Focusrite models should be more than fine for it.

I have my eyes on the €250 ($286) Scarlett 8i6 but that's because my compact setup requires a digital out to feed into the rest of my system. It offers 24-bit 192kHz recording so plenty of quality there.

 

[Apesbrain]

The two reasonably-priced USB audio interfaces that seem to get it right are the MOTU M2 and Focusrite Scarlett 2i2. Both under $200, but you'll also need RCA-to-TS cables.

 

[CtheArgie]

Thanks @Apesbrain . Those seem to be "finalists". I know about the RCA (female) to TS adaptors.

 

[digitalfrost]

I've been recording a lot of vinyl with the Scarlett 2i2. While the independent volume pots are an advantage since they allow you to center the stereo in the middle depending on other factors (LP quality, cartridge/stylus asymmetry) it's also a problem, since by default you'd like both channels to have the same volume yes?

I helped myself with TRS loopback cables, so I played a signal and recorded it at the same time and I tried to get both channels to -12dB I think. The thing is, the dials on the Scarlett are not exactly super-precise, so going for 0.2dB or 0.1dB between both channels is kinda hard.

I still like the card and you could always fix channel imbalances in software later, but the thing is, as much as it is an advantage to have this possibility on the audio interface, I sometimes wish I had a device that would just treat both channels the same.

A stepped attenuator would be the best solution.

Focusrite drivers have been not so good in the past, but I have to say since some update a couple of years ago, this thing just works.

 

[Blumlein 88]

https://www.sweetwater.com/store/detail/KompAudio2--native-instruments-komplete-audio-2-usb-audio-interface

I'd suggest the Native Instruments Komplete 2 audio interface. Why it rather than a Motu or Focusrite? Because for the same pricing it just looks twice as cool as those others according to my opinion. Any of these should do what you want.

Julian Krause review of Komplete 2.

and the 2i2

and the M2 which probably has the best measured performance of the three by just a little.

 

[Blumlein 88]

I've been recording a lot of vinyl with the Scarlett 2i2. While the independent volume pots are an advantage since they allow you to center the stereo in the middle depending on other factors (LP quality, cartridge/stylus asymmetry) it's also a problem, since by default you'd like both channels to have the same volume yes?

I helped myself with TRS loopback cables, so I played a signal and recorded it at the same time and I tried to get both channels to -12dB I think. The thing is, the dials on the Scarlett are not exactly super-precise, so going for 0.2dB or 0.1dB between both channels is kinda hard.

I still like the card and you could always fix channel imbalances in software later, but the thing is, as much as it is an advantage to have this possibility on the audio interface, I sometimes wish I had a device that would just treat both channels the same.

A stepped attenuator would be the best solution.

Focusrite drivers have been not so good in the past, but I have to say since some update a couple of years ago, this thing just works.

That is a very good point. It would be better if you have an interface that gives a read out of gain levels in db in discrete steps instead of infinitely variable knob control. As well as being able to get a match between inputs you also can go back to the exact setting later if you wish. But you would have to pay extra for an interface with that as far as I know.

 

[staticV3]

That is a very good point. It would be better if you have an interface that gives a read out of gain levels in db in discrete steps instead of infinitely variable knob control. As well as being able to get a match between inputs you also can go back to the exact setting later if you wish. But you would have to pay extra for an interface with that as far as I know.

Well, the Cosmos ADC has eight fixed gain stages that you switch between using DIP switches on the bottom of the unit. That's the only form of gain control.
Ergo you have repeatability, perfect channel match, but also a lack of flexibility.

 

[MCH]

The advantage of the scarlett is (at least here in central EU) that there are always dozens in the second hand market, and if you don't mind getting gen 2, you can regularly find it for as low as 60 eur. The Motus are not so easy to get cheap, at least over here.