Ray Tubes FAQ

The vacuum tube market is based on the false dichotomy of choosing between cheaper, easy-to-buy but lower quality new production tubes, or better quality but more expensive and rarer (sometimes much rarer) New Old Stock (NOS) tubes. We don’t believe in that dichotomy. New production can perform just as well or better than NOS, and we’re putting in the work to make it happen. Our vacuum tubes combine the ease and accessibility of buying new production with the consistency and reliability you expect from NOS.

If you don’t want to take our word for it, you can check out our reviews, many of which feature a direct comparison between our tubes and NOS tubes. We haven’t come up short yet!

Here’s the breakdown:

The CORE Collection is great for people looking for a simple upgrade from the stock tubes that came with their amp. Have you ever bought a new production tube and been pleasantly surprised by how good it sounds? The CORE Collection is like being pleasantly surprised every time.

The SELECT Collection is for those looking to get the most out of their existing systems. These tubes offer more immersion with better clarity and detail. If you’re considering an upgrade but don’t want to commit to a new amp quite yet, the SELECT Collection is perfect for you.

The RESERVE Collection is designed specifically for high-end systems. These are the very best tubes we make. They offer exquisite vocal realism and extended bass. They’re not for everyone—but they might just be for you…

As with most questions of this kind, the answer is "it depends" - on your setup, the tubes you're currently using, and what you're hoping to get out of your system. To help you decide what's best for your system, let's run through the changes you can expect when upgrading each of the three types of tubes.

Pre-amp tubes provide much of the warmth and tonality of tube audio during the pre-amp step, when weak audio signals are boosted to a usable level. For this reason, upgrading your pre-amp tubes tends to produce an immediate change in the character of the sound. Pre-amp tubes also require less break-in time than power tubes. Overall, upgrading your pre-amp tubes is usually the quickest and easiest path to noticeably better sound.

Power tubes can also have a large effect on the sound, but in their case it is much more dependent on the device your power tube is driving. Headphones, for example, are not particularly demanding, so upgrading the power tubes in a headphone amp won't produce as much of a difference as upgrading the tubes in an amp that's driving a pair of loudspeakers. Power tubes need more break-in time than pre-amp tubes as well, and require more patience for optimal performance.

Rectifier tubes are relatively rare in contemporary tube audio, but when they are present, they are critical components which power the amp itself. However, despite their importance, they are not usually a part of the audio signal pathway, and their effect on the sound is therefore relatively muted compared to pre-amp and power tubes.

Whatever you decide, we recommend upgrading all tubes of the same kind at the same time with the same product. For example, if your tube uses eight KT88 power tubes, we recommend replacing them with eight KT88s from the same product line, such as our RESERVE KT88 vacuum tubes. Tubes are a bit like batteries that way—it's not good to mismatch them.

You can buy our tubes through our extensive network of retail partners.

Two reasons. First, our mission is to make reliable and consistent vacuum tubes accessible across the board—not just to end-consumers, but to amp manufacturers, repair shops, studios, listening spaces, and so on. Selling directly to consumers is a different operation, so leaving that part to our partners allows us to serve everyone more effectively.

Second, and more importantly—we want to support local audio retailers as much as possible. Hi-fi retailers are the heart of their local audiophile communities. They’re best placed to help you with your purchase, and often they’ll have listening rooms where you can demo equipment you’re interested in. With all due respect to our copywriters, no written description can replace the experience of hearing our tubes in person!

If you're looking for a tube we don't make, let us know at help@raytubes.audio. We’re always expanding our lineup.

Okay, no one is actually asking this, but they have names and we want to tell you about them. The dark green is Forest Green. The yellow is Tube Ray Yellow. (Let us know if you spot the references.)

For the same reason that people still collect vinyl and still take photos on film. In fact, those things are only getting more popular. It’s like we all spent a couple decades enamoured by digital media and its ability to replicate sound and images almost perfectly, but now we’re remembering that there’s more to art than replication. Analog systems like tube audio provide a warmth and emotionality that digital systems can’t match.

Vacuum tubes are devices that control the flow of electrons between two electrodes. They’ve been around for well over a century, and depending on their design, they have all sorts of functions, like rectification and amplification. They used to be in absolutely everything (including early computers!) but with the advent of transistors in the mid-20th century, their uses have become increasingly niche.

In audio, they’re mostly used for their amplification properties. (Hence, you know, the word “amplifier”.) Although solid state amplifiers have been around for a while, many musicians, and increasingly many audiophiles, still prefer vacuum tube audio systems.

They’re also (fun fact!) the things that make microwave ovens work.

It depends on the tube in question. We work with manufacturing partners across Europe and Asia, because no one manufacturer covers the full range of tubes we offer. That’s a good thing—if a factory has been making 12AU7s for decades, it doesn’t really make sense to ask them to make 300Bs for us too. For each tube, we choose the best manufacturer for the job. Needless to say, regardless of where they’re made, all our tubes go through the same quality control.

Good news! We love this topic so much we wrote a whole blog post about it. The short version: we burn in all our tubes, we measure a bunch of electrical properties to match our tubes, and we check for things like microphonics. At the end, a sound engineer listens to the tube to make sure it sounds like it should.

No, but these terms are often confused because they refer to a similar concept. To make matters worse, people sometimes use them interchangeably. Here’s how we use them.

Burn-in is what we do as part of our quality control process. We put our tubes through 24 hours of use to allow electrical components to settle and to identify any faults. This is an efficient way of preventing tube failures later on, because if a tube is going to fail, it usually does so early in its life.

Break-in is what you do when you receive our tubes and start listening to them. It refers to the period when the tube’s sound hasn’t quite settled yet and you may notice it developing from day to day. It’s a normal part of tube audio. Most people report that tubes reach their peak after about 100 to 150 hours of listening, at which point their sound remains consistent until they reach the end of their usable lifespan. So when you buy new tubes, give them the benefit of the doubt until they’ve been broken in!

Tubes are a bit like tires—they’re often used in pairs or quads, and for the best performance, you want them to match as closely as possible. Otherwise you’ll get issues like inconsistent sound, distortion, or poor mileage. Matching is the process of identifying pairs (or quads) of tubes that have the same value, within a given range of tolerance, for certain electrical properties (usually plate current and transconductance).

The reason this is necessary in the first place is because vacuum tubes are analog devices. The specification for each type of tube defines what its plate current (for example) should be, but minor deviations are normal. (Major deviations make them fail our quality control.) Amp manufacturers know this, so most amps are able to adjust for this minor deviation (this is usually called the “bias” setting). But the bias adjustment applies to every tube in the amp, so if your tubes don’t match, you’ll only ever have one tube properly calibrated. Hence: matching.

Yes, but you’ll need to take care with how you install the tubes.

The purpose of matching is to ensure that the left and right channels of a stereo amplifier match. Otherwise you’ll run into issues like inconsistent volume and distortion. With a matched quad, you don’t need to worry—you can install the tubes however you like. With two matched pairs, you’ll have to pay attention to which tube goes where.

Let’s run through a simple example. Suppose your amp requires two 6SN7 tubes per channel, for four total, and you have two matched pairs of 6SN7s. The exact configuration of the tube sockets will depend on your amp, but for the sake of this example, let’s represent them like this:

L1 - L2 - R2 - R1

You’ll want to make sure that the left channel mirrors the right. Use one tube from each matched pair per channel, and make sure that the pairs are occupying the same socket. In other words, one matched pair should be in sockets L1 and R1, and the other in sockets L2 and R2. If we label your two pairs A and B, it would look like this:

A - B - B - A

(feel free to insert your own joke about 70s europop here)

OR

B - A - A - B

This will ensure that the left and right channels are balanced, and you should experience no issues.

The same principle applies to amps that need six or eight tubes. So long as you make sure to mirror them, you can use three or four matched pairs in those amps. (Or, in the latter case, two matched quads.)

Microphonics are what happens when something that isn’t a microphone makes like a microphone and transforms mechanical vibrations into electrical signals. If that something is a vacuum tube in an amp, the electrical signal manifests as an unpleasant noise. You can reduce this in two ways—by minimizing the amount of vibration your equipment is exposed to (say, not bumping into it all the time) and by using vacuum tubes that are less prone to microphonics to begin with.

We can’t do anything about the first thing, but you better believe we have the second one covered. Ray Tubes vacuum tubes are minimally prone to microphonics.

No, they’re not solid gold. That’s a little rich even for our blood. They’re coated with gold because it’s corrosion-resistant and durable.

Our Magic Coating is a layer of monocrystalline carbon that helps keep the tube cool and blocks out interference. Because applying it is a tricky process, we only use it for our very best tubes—it’s the opaque grey coating you’ll see on our RESERVE Collection. It makes the tubes rather stylish, too, if we do say so ourselves.

Yes! All of our products come with the Ray Tubes One Year Warranty. No exceptions.

The Ray Tubes One Year Warranty covers manufacturing defects.

The Ray Tubes One Year Warranty is good for, uh, one year.

Yes! As long as you have the original sales receipt, you can make a claim under our warranty, even if you weren’t the original buyer—so if you’re planning to give Ray Tubes products as a gift, make sure to include the receipt. (They do make a great gift.)

Warranty claims are handled by our retail partners. Get in touch with your place of purchase and they’ll guide you through the process.