Across the Transom: December 2023
Against Lists, Pope.L, Sonic Varnish
Gahlord Dewald :: 12/04/23 :: Mānoa
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Learn semaphore for everyday line-of-sight communication, like hanging at the beach.
Thoughts on TX-6 to Genelec
Recent forum response re: connecting a TX-6 to a pair of Genelecs with the TE mini-to-XLR Y cable and minimizing noise issues.
This all might get more/better traction in the Improving the Signal Chain thread.
TX-6, nothing connected to the TX-6 at all except main out through the size adaptor to the Genelecs via the 1/8th to XLR. Genelecs plugged into a grounded power strip connected to a grounded outlet.
Still have your ground loop in the above situation? If so, my order of testing would be:
- Ground loop isolators have never helped me much with anything, remove any in the power situation. In your system, since the only thing connected to ground are the Genelecs, you actually want stuff to flow to the Genelecs because it’s the only path to ground. The OB-4 is also ungrounded so I don’t consider that test to be revealing of much.
- Different method of getting from main output to Genelecs (splitter/adaptor/etc.), remove the TE 1/8 to XLR from the system. My first go-to here would be a simple TRS to 2x TS Y cable (an insert cable, for example) into a pair of passive or active DI boxes (something like the ART stereo DI, for example).
- Check the path from the TX-6 to the Genelecs to make sure your audio cable is not running parallel to any power cables or computer cables of any kind.
- Confirm that the Genelecs are grounded and plugged into power strip that is grounded and that the power strip is plugged into an outlet that is grounded.
The main issue you are dealing with is that the main out of the TX-6 is an unbalanced stereo TRS signal.
The XLR your Genelec is expecting is a balanced mono signal. In that XLR plug it’s expecting one copy of the audio, one inverted copy of the audio, and one ground. I don’t think there are any electronics in your TE cable to create that inverted signal. And there are not enough segments on the plug to carry enough signals run 2 XLR cables (you’d need something with 5 segments to split into 2x XLR, like on stereo field recording mics). I doubt the TX-6 main out would work with a 5 segment plug either.
My guess, not having tried this configuration, is that the Genelecs are receiving a quieter total audio signal than expected; they are expecting to take the audio and the inverted audio, flip the inverted (and in the process invert any noise picked up along the way), and sum the two signals together. Since they aren’t getting the inverted signal they are summing the signal with nothing and thus operating with a higher noise floor.
I don’t know what those TE 1/8 to XLR are supposed to do, but I don’t see how they can generate a balanced audio signal because they just don’t have enough segments to carry the signals and it doesn't look like there are the electronics to generate the inverted signal.
I think you’re going to need an actual DI to run this system without a high noise floor and/or ground loop.
tldr; You are trying to match a piece of gear that has unbalanced output to a piece of gear that expects balanced input. You will most easily resolve this with a Y cable, stereo DI box of some kind, and some XLR cables to connect the stereo DI to the powered speakers. The DI box will have a ground lift that you can fiddle with if the connection between your Genelecs and ground is shoddy.
A collection of 25000 single-cycle audio files for wavetables.
Someone with an RME Babyface (one of my personal favorite little converter boxes) was asking about exploring microphone preamps. Their main use case involved guitars and synths, however. Here's what I suggested:
If you want to add color to your sound, then I would encourage you to look for colorful preamps. Your RME Babyface, as you note, has very nice clean preamps. Do not look for clean sounding preamps because you already have 2 in that Babyface.
Instead, look for 2 colorful preamps. For this, it is truly a matter of taste, what kind of color you want. Very very broadly speaking, preamps for color tend to come in two basic flavors:
- “British” (anything that looks or uses Neve-like words/1073 etc, maybe mentions the transformers as Carnhill) and
- “American” (anything that looks or uses API-like words, maybe mentions the transformers as Cinemag). Tons of great preamps in either style.’
There are of course other styles usually distinguished by the kind of transformer, use of tubes etc.
If you can’t hear the distinctions between these things then take the time to listen closely to examples, ideally in person if you have friends who own any kinds of preamps. Learn which you like and then get something in that flavor.
Mic Pres to listen to with the goal of hearing how they alter the body of the sound, listen just to hear them, don’t worry about whether you “like” the sound, just listen to hear the differences:
- UA610 – classic tube preamp/DI
- Electrodyne – one of my favorites in the Cinemag category
- Neve 1073 – very popular design
- Neve 88 – not very popular but an example something clean but with refined character
- Chandler TG2 – EMI clone
- AEA TRP or RPQ – this is an example of a clean mic pre, it’s designed for ribbon mics and has tremendous db on tap and a low noise floor; you don’t need this but use it as an example vs the others to get a sense of sound
The other things that distinguish mic preamps are what kind of boring features they have: pads, phase flips, DI (and where does the DI hit the transformer), some have EQ sections, some (like the 6176) have compressors, what’s the routing like, that kind of thing. Super boring but there may be some features that turn out to be really handy.
To complicate things: 3 of the 4 things you want to do are DI. And your mic isn’t terrible but if the vocals recording were the thing you want to make nicer then a mic purchase would have a larger impact than the pre-amp.
You may be better off getting a really great DI box instead of a mic pre.
Allen Farmelo's sonic varnish article has greatly informed my approach to recording and mixing with outboard audio gear. This article made the entire concept of saturation etc start to make sense for me.
Before that, I was prepped to take his lesson to heart by being a bassist. For bass it’s very common to give the track one pass of compression to get things generally into range (a “surgical” or “technical” compression) and one pass of compression for character. Stacking 1176s one after other on a bass track is just a super normal and obvious thing to do. From there, the leap to the varnish concept becomes very straightforward.
At this point I apply saturation to the point where I can jusssst barely hear it. Then dial it back a tiny tiny bit, knowing that as I do this across multiple channels and several passes in the recording, mixing, and mastering processes the whole thing adds up. This is double/triple/quadriple important for me when using tape (either one of my Nagras, which by design have practically “invisible” tape character, or a plugin or one of my cassette decks).
The things I mention below are based on investigating and learning about that concept over the past 12 years and in response to a friend wondering how to approach a 1073 clone in relation to a 1073 clone with a different input transformer.
For me, with all saturation devices (preamps, random analog circuits, transformer things, tape) the best outcomes are from a small amount applied across a wide number of channels. Or a small amount applied repeatedly to a single channel (once on the way in, once or twice during the mix for in/out to other analog gear, once during mixdown, once during mastering). Or ideally both: all the channels going through a process like above.
For something like a 1073 which was found on a mixing board, the idea is to have all the channels of everything hitting it. The music would hit the preamp of the board and then go to tape during tracking. Then the music would hit the preamp again going from tape to the mixing board for mixdown. Then the full mix might hit it once more as 2-channel tape was mastered.
In all of these instances, the engineer would have been trying to avoid distortion etc to get as clean a sound as possible. Certainly it’d be used for fun distortion now and then, but the default setting of the engineers would be trying to keep it fairly clean and the characteristics of a 1073 reveal themselves by being present on all the tracks of the mix.
Also, a lot of peoples’ love for specific circuits, like the 1073, is rooted more in their sense of nostalgia or the result of their personal identity as a specific kind of musician and so on. Which is absolutely cool. But you can’t hear nostalgia with your ears or see it on a meter. So it’s one of those things that you can’t really judge based on what you read in forums.
It could be that, for your personal hearing/nostalgia/identity and listening environment, the effects of the 1073 don’t produce much emotional response. And that’s ok and good for you to learn about, investigate, and strengthen your trust in your own ears and instincts.
It makes sense that they sound the same at low input levels as what you describe is that the difference is mainly the input transformer and if that isn’t saturating then they are very similar circuits.