Converters


#1

I came across a “studio grade” converter on someone’s bit of used eurorack kit. The machine is almost 20 years old, but the expired retail listing on sweetwater was almost $3000 US.

It’s a Lucid 88192, with 8-channel, analog to digital/digital to analog, multi-format converter – 4x ADAT-optical. The price is $650 CAN.

So a few questions if anyone cares to comment. For one, I am not in the market for this. But I might be in the market for it one day or something like it. Right now I am using either the converters on the ES-8, the converters on the elektron Analog 4 mk1 or the converter on my Apogee Jam 96k.

I like the idea that I can expand the inputs on the ES-8 with ADAT, but I am curious how having something old but industry grade compares to having something contemporary but home studio grade. I suspect that something like the Lucid 88192 would be worth something, but I am suspicious because of how much digital technology has advanced in the last 20 years, especially in terms of music production equipment.

I imagine that this is actually a very nuanced topic as the focus leads closer to the point at which the analog to digital conversion is made. Are there drawbacks to these older machines? Do the latest ADAT preamps out perform by miles, or is it a matter of taste? I am not sure where the ‘taste’ would be located on a converter.


#2

You would need to investigate an older unit like this very carefully before purchase. As you mention, standards change over the years and something that was state of the art then may not be very usable now. Support for an older piece of gear is always questionable. The user’s manual I found was copyright 2009 so it’s probably closer to 10 years old rather than 20, but even so, I would be careful. In this case, the unit only has line level inputs so it would need a preamp to be used with a mic or instrument. The digital outputs other than the ADAT are in a format I’m not familiar with but definitely not USB. You could buy a pretty nice interface for $600 that would probably perform just as well with more flexibility.


#3

That’s the thing. That’s really the heart of it. I am not entirely convinced that that is the case. That would be the view for many.

‘State of the art’. I own a 1991 Toyota 4Runner. I like to work on it, I like the shape of the grill, the matte patina on the old red paint, etc… The new 4Runners go for a lot of money. I prefer how my old one looks; just as I am happy with my A4 mk1 since, as @robertsyrett pointed out, the form factor is nice.

Obviously in this case ‘form factor’ is not an issue. One thing I really appreciate about the modular synth community is that there are enough people who know one chip from another enough to now what certain boards are worth.

Is the converter in my economic 1 channel 96k Apogee Jam ($129US MSP) better than the converter in this Lucid 88182 ($2,729US MSP)? The Jam 96k was out in 2014, I believe. While this Lucid beast was out in 2009, you mentioned. That’s 5 years, 1/20th of the price.

I like my through hole fuzz pedal, but I don’t know how one judges converters. I think it is a very interesting topic that I would like to know more about.


#4

It wouldn’t surprise me if in a studio environment the Lucid would outperform any of the mid-priced interfaces on the market. I’m not arguing that the Apogee or something similar would be equal, only that given that there are limitations in the rest of the gear, you would be hard pressed to hear any difference between the Lucid and another $600 dollar interface which would provide more capabilities. For example at $699 the Focusrite Clarett 4pre has better specs and offers a USB connection, 4 line ins, 4 mic preamps, 4 analog outputs, 2 headphone outs, SPDIF in and out, MIDI in and out and 8 ADAT inputs. Of course it all depends on what you need and I’m sure the Lucid would be a good unit if it meets your needs. Beware of anything that requires drivers, my son had a perfectly good interface on his Mac until an O/S upgrade when it stopped working. No new drivers and the company no longer supports it. Now it’s just a piece of junk.


#5

What a shame. One of the reasons I deal with Mac is because the whole Windows drivers thing just kills me. I didn’t know it was also a problem with Mac hardware. We could really use some kind of a stamp like ‘fair-trade’ or ‘gluten-free’ but for electronics. Some kind of standard in which, if you really want to, you can keep running old stuff. It should be the same thing for cars. All these cars we make are absolute junk – even the plastic cars for rich people are often slapped together with the same materials, by the same automotive workers, on the ‘lexus line’, which is about 10 feet over from the cars for blue/white collar people.

It’s hard to say. I am thinking of plugging something into the ES-8 that will increase the amount of inputs. But I am also just really intrigued by converters.

For the pre’s, I think you could deal with pre-amps as a separate concern, no? Makes me wonder what pre-amps are all about. I mean usually they are instrument specific. Like I would get a preamp for my bass, right? So then what is going on with preamps built into interfaces? What does it have to do with gain staging?

The usb connection I don’t quite understand what I would need that for. I don’t need the headphone outs, probably not SPDIF, and I am not sure what I would need midi for. The way I see it, my audio interface is the ES-8, and I thought that the ADAT connection might be a good way to introduce some amazing converters that many people wouldn’t even know to check out.

Feel free to ignore most of the post here. It is such new territory, but also fun to try and get my head around.


#6

I agree wholeheartedly regard Windows, particularly with regard to audio. It basically sucks. For USB devices we now have a pretty good standard. In the bad old days Macs required audio drivers just like Windows, but now if a USB device is “class compliant” (which means it conforms to the standard for its class), it should work with the Mac as well as iOS devices with no drivers. (at least for audio and MIDI) Maybe someday this will also apply to things like USB storage for iPads although I think Apple favors the “store it in the cloud” approach.
In your particular case I can see the appeal of something like the Lucid. My point wasn’t that the Clarett was a good fit for your needs, only that $600 can buy something pretty nice. What about a second ES-8? I’m not sure if you can connect them via ADAT but @robertsyrett would certainly know.
Instruments often benefit from specific pre-amps (e.g. bass, piezo acoustic pickups etc. The preamps on devices like the Clarett are really more aimed at microphones, although they will also accept instruments and line level inputs. They aim to provide impedance matching and gain with very low noise and an even frequency response. Instrument specific pre-amps generally also provide some frequency shaping. The Fishman pickup on my dulcimer has a 3 band equalizer, and a notch filter and phase inversion switch to help suppress feedback. These days I think it’s more common for instruments to feed a pedalboard that includes a pre and deal with line level out of the board. If you don’t need a mic input then a straight converter might be a better option.


#7

Attaching an ADAT-based converter to your ES-8 seems like a solid idea. No drivers required so the setup will be compatible for a long time.

As to whether the Lucid is worth it, I would try to check the repair costs.

FWIW, I have a Focusrite OctoPre which works fine and includes mic pres.


#8

I’ve been real happy with everything I’ve gotten from Focusrite.


#9

I was just playing a guitar that my dad built and he put a Fishman pickup in there. I was very impressed. This particular model was able to crossfade between two sound sources – the saddle and a mic, I think. It made a world of difference. So in that example I don’t see the need for the extra preamps. Maybe it is a matter of getting more headroom so that the sweet spot ranges are greater, so easier to mix everything at the correct levels?


#10

Thought I would add this video to the thread here. I found it gave some fast insight for someone with little knowledge of the ADC procedure.


#11

Really with the Fishman or another active preamp, you should have enough gain that another preamp wouldn’t add much. I guess it depends on what you’re feeding. As long as you have enough gain to get a decent recording level without too much noise, you should be alright. I prefer to do most of my eq, reverb, etc. post recording, but that’s just a personal preference.


#12

Just wondering about how the ES-8 works. Does it send the audio through the chip in the Macbook to do the ADC work their? When I looked at the sheet on the ES-8 I didn’t see mention of an ADC. However, the Disting sheet mentioned this:

X & Y inputs, A & B outputs:

  • ADC: 24 bit, THD+N -93dB, Dynamic range 99dB, SNR 99dB
  • DAC: 24 bit, THD+N -94dB, Dynamic range 105dB, SNR 104dB
  • Sample rate: 75kHz
  • Z input sample rate: 75kHz

CPU: Microchip PIC32MX at up to 50MHz, hackable , open source code framework available.

The ES-3 mentions this:

  • D/A conversion: 24 bit, 113dB SNR typical

I am now looking at the Digitakt and wondering what the ADC/DAC setup is there. I am glad I started looking at this because I think it is good to know where you are building an analog world and where you start to introduce conversions. I would like to someday be able to do sampling. However, I hadn’t really thought about converters for that use case.


#13

The DAC/ADC would have to be in the ES-8. There’s no way to send an analog audio signal over USB.


#14

okay. so then the ADC/DAC nodes are directing signal flow more than doing any hard math – or, rather, Audulus makes use of the chips? Forgive me I am not a computer science kid, nor a recording engineer. But if I am this deep I should know some of this.


#15

All the conversion is done within the ES-8. Tthe ES-8 generates an internal clock and samples the inputs at the selected clock frequency and converts the samples to 24 bit integers and sends them serially to the host via USB. Likewise the outputs are received via USB, converted from digital to analogue signals and output from the ES-8. With an active ADAT connection the clock can be sourced from the ADAT signal, but otherwise operation is the same. From looking at the user manual, it looks like connecting 2 ES-8s via ADAT would work, giving you 16 outputs and 8 inputs.


#16

Thanks for the rundown. I really don’t have room for another ES-8. Still makes me wonder about the ADC/DAC quality. Obviously the ES-8 is not intended for high end conversion.


#17

I guess it boils down to how good is good enough? The ES-8 supports sample rates to 96K which should be fast enough for anyone. The noise and THD specs are also pretty good. A dedicated audio-only interface might outperform it, but how would you judge? You can objectively measure noise, distortion, phase response etc. using very expensive lab equipment but the end user has no choice but to use the signals they have access to. If you use Audulus for example to compare two units, how would you know which one was the more accurate? You could use a microphone and compare the output to the original source, but now you’ve introduced several more elements into the mix. A $3000 Neuman mic is definitely better than a $80 Shure. The same is true of mic preamps. Personally I believe that particularly with respect to digital electronics you rapidly reach the point of diminishing returns. The quality of the analog circuitry front-ending the converter is obviously important and clock jitter can introduce unwanted artifacts, but once the analog to digital conversion has taken place it’s all just numbers. There may be some justification in a studio situation where you may be dealing with a large number of channels, but IMHO the high end consumer DAC/ADC market is more about separating the gullible from their money than any actual performance gains. It’s the same impulse that drives the high-end audio market in general. I once had a Best Buy salesperson try to sell me a $80 HDMI cable on the basis that it was very low noise, but HDMI is a digital signal and noise isn’t really a factor. As long as the cable meets the HDMI specs for bandwidth etc. it will work.


#18

These are obviously valid points and I trust your judgement on most of it.

To cut to the heart of it…If I ran my analog signal through just the ES-8 (remember, I have a ‘pure’ path right now), then I ran everything through this Lucid converter and A/B’d the two I am willing to wager that there would be a perceivable difference. Side by side perceivable. But I think the difference would be hard to detect without the A/B. But I don’t really know.

There is a video I wanted to post but I didn’t because I post too much here on the forum anyway. I found the whole video useful and entertaining in many ways. It fits well with this topic and I am sure someone will get something out of it.


#19

If there is any difference sonically, it would be most detectable on acoustic instruments, not synths. Synths don’t have as complex harmonic content as stuff like the human voice or guitar does. You’re not using the ES-8 to send audio in and out of a $20k compressor in a mastering studio - it’s more than adequate for any synth recording stuff.

Remember too that a lot of great hits were made back in 16-bit days - it still sounds good now. Has much more to do with recording technique and composition than it does the equipment.


#20

Not so sure. Depends on the patch. I am also a user of acoustic instruments.