Fosi GR70 Review Recap by Nick’s Listening Space

Introduction: Exploring Tubes Without Breaking the Bank

If you’ve ever been curious about tubes but didn’t want to dive straight into high-priced gear, the Fosi GR70 tube headphone preamplifier might be the perfect starting point. At just $200, it offers a real taste of tube flavor, warmth, and immersive sound—all in an affordable package.

Nick from Nick’s Listening Space recently shared his in-depth impressions of the GR70, and his verdict was simple:

“I’m really loving this thing… probably one of the better listening experiences I’ve ever had at this price point.”

Let’s walk through Nick’s thoughts on the GR70—its build quality, tube performance, headphone experience, and why he thinks it’s one of the most fun budget amps out there.

Build Quality & Features: Solid for the Price

Nick starts by saying the build quality is completely adequate for $200—and actually more impressive than you’d expect at this budget.

Here’s what you get:

• Front panel controls: Volume knob, tone controls with tactile feedback.

• Impedance switch: Low (16–120Ω) and High (120–300Ω).

• Headphone outputs: Both 6.35mm and 3.5mm jacks.

• Rear panel: High-quality RCA input, 12V/3A power brick.

The tubes included are:

• 5654W tubes (common and easy to source).

• 6AC7 military-spec novel tubes (9-pin, not to be confused with the more common 8-pin 6CA7).

Nick notes the unusual metal housing and worn lettering, suggesting they might be new old stock.

Overall? The GR70 feels more serious than its price would suggest.

As a Preamp: Tube Flavor on a Budget

Nick tested the GR70 both as a headphone amplifier and as a dedicated preamp in his system.

Compared to his Schiit Freya+ ($1,000+ with tubes), the GR70 held its own surprisingly well:

“This is so close to my Freya+. Going back and forth, I’m not quite fully getting a sense of difference… if anything, this might actually give me more tube flavor.”

What does that mean? The GR70 adds:

• Bloom and euphonics often associated with tubes.

• A more colored but musical sound compared to Freya+’s clarity.

• Strong synergy with Fosi’s V3 Monos and Topping D53 DAC.

He pointed out that the D53, being transparent and resolving, paired especially well with the GR70 because the tubes added body and character to the sound.

Tone Controls: Simple but Effective

The GR70 includes bass and treble knobs, which Nick appreciated for fine-tuning:

• There’s a 12 o’clock “click” where the tone controls flatten out.

• Out of the box, it seems to have a slight bass boost.

• For bass-light gear (like his FLS50 speakers), that extra low-end helps flesh things out.

• If the bass feels too much, it’s easy to dial it back or brighten the treble.

Nick felt this flexibility made the GR70 fun and versatile, especially at the entry-level.

Headphone Performance: Pure Tube Enjoyment

Nick tested the GR70 with his HiFiMan Sundara and Sony MDR-7506 headphones. The results shocked him:

“With my Sundaras, this was nothing short of one of the better listening experiences I’ve ever had.”

The sound was lush, immersive, and expansive. The bass boost added body, while the tube character created a larger sense of scale and space.

GR70 vs. Niche PID

At a similar price point, Nick compared the GR70 to his Niche PID ($189), which is often said to have a “tube-like” sound.

• Niche PID: A solid-state amp EQ’d to sound warm, but not true tubes.

• GR70: Real tubes, more authentic bloom and euphonics.

Nick summed it up:

“The Niche PID is trying to mimic this. The GR70 is the more pure experience.”

For him, the GR70’s soundstage lushness and scale made it clear which one was more enjoyable.

A Special Listening Experience: Immersed in Space

One of Nick’s most powerful moments with the GR70 came when listening to “La Segunda Noche” by Chesky Records—a live album recorded in a church.

The GR70 created such a convincing soundstage that he repeatedly took off his headphones, thinking his speakers were playing.

“The scale and space were so palpable. I was so immersed… it transported me to that room on the day the recording was done.”

As an architectural designer, Nick connected this to his passion for space:

“Music has the ability to etch a room… great recordings with tubes transport you into that space, with depth, width, and height.”

That kind of immersion is what tube gear does best, and the GR70 delivered it beautifully.

Handling Poor Recordings

Not all music is recorded in a grand hall. Some tracks are close-mic’d vocals in a studio booth with little natural space.

Here too, the GR70 helped:

• Added bloom and warmth to otherwise flat recordings.

• Gave intimacy a bit more space and presence.

• Made even low-quality mixes more listenable and fun.

For Nick, this versatility made the GR70 even more appealing.

Tube Rolling Potential

While the GR70 does allow for tube rolling, Nick cautioned that options may be limited:

• 5654W tubes: Plenty of affordable choices (Mullard, Telefunken, etc.).

• 6AC7 (9-pin novel): Less common, not as many variations available.

Still, with tubes costing under $20 each, rolling remains inexpensive if you want to experiment.

Value & Fun Factor

At the end of the day, Nick calls the GR70 a “great budget tube amp” and a fun device for anyone curious about tubes.

“For $200, you can buy this and start exploring the realm of tubes… it’s not for perfectionists, but for people who want to play around with color and have fun.”

He even suggested it might replace his Niche PID as his go-to “fun amp.”

Conclusion: Nick’s Final Thoughts

Nick’s Listening Space made it clear: the Fosi GR70 punches far above its $200 price tag.

• As a preamp, it brings tube bloom and warmth close to gear 5x its price.

• As a headphone amp, it delivers lush, immersive sound—especially with open-back planars like the HiFiMan Sundara.

• It’s fun, flexible, and forgiving, making even poor recordings enjoyable.

His verdict?

“I’m loving this thing… one of the greatest listening experiences I’ve had at this price point. Probably going to replace my Niche PID as my fun amp.”

For anyone looking to dip into tubes without spending thousands, the Fosi GR70 is an easy recommendation.