[Guitarist’s Perspective] Equipment that is Thought to Improve Sound Just by Passing it Through Part 1 - Direct Boxes

“Passing it through makes the sound fuller,” “It makes the sound more prominent,” “It adds brilliance to the sound”
People use various ways of saying, but after all, it all comes down to changes in the waveform or spectrum. It’s nothing more, nothing less. What’s important to understand is that even if these changes make the sound seem better, it doesn’t mean the amount of information has increased.

In fact, the information tends to decrease. For example, once sound is cut by a filter, it can’t be restored even if boosted later. I believe audio equipment reduces the amount of information in the input signal while altering the balance to shape the sound. If the sound doesn’t change much, then I think it’s better not to use it.

Direct Box (DI)

I occasionally get asked, “Will the sound improve if I use a DI?”
A DI is a piece of equipment that converts the signal from a guitar or bass into a low-impedance balanced signal, improving noise resistance over long cable runs and allowing direct connection to a mixer or interface’s mic input.

Compared to running a long cable without a DI, using one can significantly reduce noise. You might be surprised by how degraded the high frequencies sound if you connect a guitar or bass directly to a mixer, but a DI can prevent that.
This might be why there’s a perception that “using a DI reduces noise” or “using a DI improves the sound.”

Sometimes, people consider using a DI even when their audio interface has a Hi-Z input, or they try to connect a mic to a DI.
If your mixer or interface has a Hi-Z input, impedance isn’t an issue, and the sound won’t degrade without a DI. Additionally, for cable runs of just a few meters, an unbalanced connection won’t pick up much noise, and mics are inherently balanced connections.

Gear is often romanticized, and it’s understandable to think that “just running the signal through it might make the sound better.” However, I encourage you to listen carefully and make judgments with your own ears. If you think the sound hasn’t changed much, it probably hasn’t improved!

If there were DIs that actually improve sound quality.
That being said, there are indeed some DIs that seem like they might improve sound quality just by using them...

Warm Audio / Direct Box Active (Active DI)

Rupert Neve Designs / RNDI

BAE / PDI Direct Box

Just by looking at these DIs, you might feel like they’ll make the sound better, right? Lol.

These DIs feature high-quality components and circuit designs that minimize the loss of information due to noise or distortion while actively altering the information balance. This change in balance is conveyed to the user as ‘color’.
While it doesn’t actually increase the amount of information, this color often leads people to perceive the sound as improved.

I’ve tried the BAE and Warm Audio DIs mentioned above, and I did notice a difference compared to using the Hi-Z input on an interface. The difference was very subtle, but I recall feeling that the sound became slightly clearer. I never compared them side by side, but that might have been even more interesting.

When testing gear, what’s important is:

• There should be some physical basis for the results.
• Don’t start with the preconceived notion that the sound will improve.
• Trust only the information your own ears perceive.

If anyone agrees with these points, I’d be glad.

I’m not sure how to wrap this up, but Sound House will continue delivering the romance of gear to music fans across the country, so please keep buying from us!