Pros and Cons of Tube Phono Preamps
I recently upgraded the phono preamp I use with my Rega Planar 2 Turntable on my home stereo.
And in the process of researching and finding the best preamp for my setup that wouldn’t break the bank, I looked quite a bit into affordable vacuum tube phono preamps.
Personally, I have a preference for the silky smooth, warm and pleasant sound characteristic that is the big selling point for vacuum tube amplification. As opposite to a brighter and more analytical sound that is on the other end of the spectrum.
At last, I did however choose a Rega Fono Mini A2D phono preamp. Which is not a vacuum tube phono preamp.
But I thought I should share what I found to be the pros and cons of an affordable vacuum tube phono preamp in this article. And why I personally choose to go for a regular solid-state phono preamp at last.
I have also included a short review section where I discuss the most popular and affordable tube phono preamps I found on the market today.
Update: I have now invested in a Pro-Ject Tube Box S2, which is a tube phono preamp. You’ll find a link to my review in the end of this article.
So, what are the main the pros and cons of a vacuum tube phono preamp?
The main pros of tube preamps are their ability to reproduce sound with a warm and pleasant character and their vintage look and feel with the tubes glowing as music is played. The main cons are the higher cost, the required warm-up time and the need to replace the tubes at certain intervals.
That was the short answer. We’ll go much more in detail on each advantage and disadvantage in the coming sections.
What are the differences between tube preamps and solid-state (regular) preamps?
A tube preamp uses vacuum tubes to increase the amplitude or power of a signal.
While a regular (solid-state) preamp use transistors and operational amplifiers to do that job.
The signal that is coming from the turntable’s cartridge is very tiny. Usually around 5mV for a standard MM cartridge. And therefore needs an additional stage of amplification before it reaches the same signal level that is outputted from for example a CD player or a digital streamer.
And this need for extra amplification is half the reason why a turntable needs a phono preamp, while other signal sources (CD players, etc.) does not.
The other half of the reason for why a turntable needs a preamp is the RIAA correction. When records are produced, the bass (lower tones) is heavily reduced before the music is carved into the record. This is done to reduce the physical space each and every song needs on a record. To be able to fit more songs on each side. So the other important task of the phono preamp is to significantly increase the bass and reduce the treble to correct this process so the music will sound right again.
In a tube phono preamp the circuitry needed to amplify and RIAA correct the signal is built around vacuum tubes. While this circuitry is built around transistors (or operational amplifiers) in a regular solid-state phono preamp.
Tube amplifiers respond differently from transistor amplifiers when signal levels approach and reach the point of clipping. In a tube amplifier, the transition from linear amplification to limiting is less abrupt than in a solid state unit, resulting in a less grating form of distortion at the onset of clipping. (Source: Wikipedia)
And this is the main reason why so many studio musicians, guitarist and home stereo enthusiast prefer tube amplification. The softer clipping that tubes provide results in a warmer and more pleasant sound character.
The PROS of a Vacuum Tube Phono Preamp
1. Silky smooth warm pleasant sound
A home stereo that uses tube amplification will usually have a much warmer and more pleasant sound character than regular solid-state transistor based amplification.
This is provided by the softer clipping and transient characteristics of the tubes.
And to break this down even further, tube amplification is often preferred by home stereo enthusiasts for two specific reasons.
The first being that they just have a strong preference for warm and pleasant sound overall. And want to “color” the sound character of their stereo in that direction as much as possible. The warmer the better.
The other reason is that they have other stereo components (speakers, cartridge, etc.) that are on the brighter/cooler side of the sound spectrum. And they want to balance that out by including a warmer sounding tube preamp or amplifier to achieve a good sound character balance between the different stereo components. This is often called “balancing” in the world of Hi-Fi and home stereo.
2. Looks really cool
The other and more minor reason for selecting tube preamps is their cool and retro look and feel.
It is really something special when you turn down the lights and listen to some nice relaxing music while the tubes are glowing in the dark.
This is however not a feature that we can take advantage of on all tube phono preamps as the tubes sometimes is hidden inside the chassis. It is also dependent on the type of tubes. Some tubes glow more than others.
The sound of a tube preamp is to a large degree determined by the type and quality of the tubes. (As long as it is an authentic tube design.) So there is always an option to upgrade to different and better tubes to change and improve the sound character and sound quality down the line.
The CONS of a Vacuum Tube Phono Preamp
As a guy that doesn’t have a huge budget to spend on stereo equipment (hopefully in the future), the biggest con I found with tube preamps is their cost.
The tube enthusiasts don’t seem to be at all interested in gear below $1000. And frankly, there is not a lot of tube preamps to choose from below $1000. And below $300 or so it is really hard to find anything that seems to be worth buying for someone that is passionate about sound quality.
There are some budget ones that can be bought for less than $300. But they don’t seem to always be authentic tube designs and they generally don’t get a lot of love and praise from the vinyl community.
Some of the cheap tube preamps frankly seem a bit gimmicky. Like a regular solid-state design with a tube thrown into the middle to make it appear like a tube design… Just an observation, I might be wrong…
In my opinion, you can buy a good regular solid-state phono preamp for less than $200. At the time this article is written. Like the award-winning Rega Fono Mini A2D we talk about a lot on Vinyl Restart.
But for a tube phono preamp, it doesn’t seem like $200 is enough to buy a good one. A larger budget is needed.
2. Warm up time
As opposed to a solid-state phono preamp, that can be switched on at the very moment you want to listen to music, tube preamps need time to warm up for they will sound their best.
The warm-up time is usually around 30 minutes.
So a stereo that uses a tube phono preamp and tube amplification in general, needs a little planning in its daily use. Like turning it on 30 minutes before you start spinning vinyl to give it time to heat up.
3. Tubes wear out
As oppose to transistors that last for decades, tubes wear out and need to be replaced at certain intervals.
So in addition to the higher purchase cost, there are running costs as well.
And tubes can be quite expensive. So the running cost might be significant.
This gets even worse if you are the type that sometimes forgets to turn things off. Forgetting to turn off a tube preamp after use will make the tubes wear out even quicker.
The Best Affordable Vacuum Tube Phono Preamp
In my opinion, you can buy a decent solid-state (non-tube) phono preamp for $50 to $100. And a good one for $100 to $200. Two favorites of mine are the Pro-Ject Phono Box MM and the multi award-winning Rega Fono Mini A2D that I use myself (Amazon links).
So this will be our frame of reference when we’ll discuss the value for money of affordable tube phono preamps in this section. A decent one for less than $100. And a good one for less than $200.
Vacuum tube phono preamps get expensive quite quickly, so there aren’t many to choose from in the $50 to $200 range. Of the four vacuum tube phono preamps I’ve found to be the most popular below $500 right now, only one is priced comfortably below $200.
Please let me underline that I am no guru on tube phono preamps. So please do your own research as well. With that said, my findings are based on lots of research in communities and forums where people really are gurus on these things. So there should be a lot of value to take home in this after all.
Let’s look at the 4 tube preamps I found to be the most popular below $500. Starting with the cheapest one based on the pricing at the time this article is written.
1. Nobsound Little Bear T7 ($)
The only one on this list that costs way below $200. Unfortunately, it has received really mixed reviews. It seems like it has been designed with too much emphasis on low cost. At the expense of sound quality. But if you want a tube phono preamp as cheaply as possible, this seems to be the best choice. In its favor, it looks really cool and the sound quality is reported to increase quite a bit if you buy a set of better tubes to replace the originals right from the get-go.
Click here to read reviews and check price on Amazon.
2. Bellari VP-130 ($$)
Just like the Nobsound Little Bear T7, the Bellari VP-130 also receive mixed reviews. Some claims that it is not a real tube preamp, but rather a solid-state preamp with a tube thrown into the circuitry to make it appear like genuine tube preamp. I have seen pictures of the internal circuitry that indicate some truth in that. But a lot of users seem to love it as well.
Click here to read reviews and check price on Amazon.
3. Nobsound Little Bear T11 ($$)
Unlike the two tube preamps we have discussed so far, this one seems to get a bit of love and praise in the vinyl community. Even among the tube enthusiasts. For my money, this is one of two tube phono preamps I would consider buying to use with a decent turntable. The other one is the Pro-Ject Tube Box S2 that is next on the list.
Click here to read reviews and check price on Amazon.
4. Pro-Ject Tube Box S2 ($$$)
The Pro-Ject Tube Box S2 seems to be regarded as real quality item by the vinyl community and a very good option to consider for an affordable tube preamp that will deliver a good sonic performance.
This is made for people that are passionate about by sound quality. No gimmicks reported here.
For a good YouTube review of the Pro-Ject Tube Box S2, please check out Techmoan’s review by clicking here.
It is hard to compare it to the Nobesound T11 without being able to test and compare them directly. But all the bad reviews I read about the Nobesound T7 got me hesitant about the Nobesound T11 as well. Might be irrational thinking, but anyway.
So the affordable tube phono preamp I consider as the best candidate for my Rega Planar 2 is the Pro-Ject Tube Box S2.
Click here to check price on the Pro-Ject Tube Box S2 on Amazon.
This article summarizes the main pros and cons of (affordable) tube phono preamps.
And from what I found, the main con for normal vinyl enthusiasts with a regular budget to spend on home audio gear is the cost associated with buying a good quality tube phono preamp.
I good regular solid-state phono preamp can be bought for less than $200. In my opinion.
The multi award-winning Rega Fono Mini A2D is a good example.
To get an authentically designed tube phono preamp with equal sound qualities you will need to spend a bit more.
So going for a regular phono preamp is the safest bet if you have $200 budget.
If you can up the ante to $400 or so, and want the warm smooth sound of a tube phono preamp, the Pro-Ject Tube Box S2 is what I have found to be the best and safest choice.
Update: I have now invested in a Pro-Ject Tube Box S2. Read my review here.