Drop THX AAA789 vs Schiit Jotunheim 3 Review

If you're deep enough into headphone audio to be shopping for a dedicated amplifier, you've almost certainly encountered both of these names. The Drop THX AAA 789 and the Schiit Jotunheim 3 sit at a fascinating crossroads in the mid-fi amp market — one is a clinical, measurement-obsessed benchmark machine, the other is a flexible, feature-rich desktop workhorse with a distinctly American personality. One Reddit user put it plainly: they upgraded from the 789 directly to the Jotunheim 3, pairing it with a Modius DAC and running Focal Elex and HD6XX headphones. That real-world upgrade path tells you a lot about where each product sits in the food chain.

This isn't a battle between a bad amp and a good one. Both are genuinely capable pieces of gear. The question is which one is right for your setup, your headphones, and how you listen.

Drop THX AAA 789

The Case For It

The 789 built its reputation on one thing: measurements. When it launched, it posted distortion and noise figures that embarrassed amplifiers costing three to five times as much. THX's Achromatic Audio Amplifier technology essentially eliminates audible distortion, giving you a signal path that's about as transparent as solid-state gets. If your headphones are good, the 789 gets out of the way and lets them do their job.

It's also a balanced amplifier with both 4.4mm pentaconn and XLR outputs, meaning it can fully exploit balanced headphone cables — a feature that used to cost significantly more. At its price point, that's genuinely hard to beat on paper.

For planars like the HE-400i or any moderately sensitive dynamic driver, the 789 delivers ample power with a noise floor so low it's essentially inaudible. Audiophiles chasing objective performance metrics have praised it consistently since its release.

Where It Falls Short

Here's the honest truth: the 789 is a one-trick pony, and that trick is "measure well." It has no DAC section, no EQ, no Bluetooth, no modular expandability. You buy it, you plug it in, you listen. That's the entire feature set.

The form factor — a flat, horizontal slab — is divisive. It was designed to be racked or stacked rather than used as a standalone desktop piece, which means if you want it at a comfortable listening height, you'll need to plan your desk layout around it. The volume knob feel and overall build quality are functional but uninspiring at the price.

Perhaps most critically: as the Reddit upgrade thread makes clear, many users treat the 789 as a stepping stone rather than a destination. It's excellent for what it is, but listeners who develop their tastes — especially those running high-impedance dynamics like the HD6XX or HD800 — often find themselves wanting more body and dimensionality than pure transparency provides.

Schiit Jotunheim 3

What Makes It Special

The Jotunheim 3 is a different animal. Where the 789 is a single-purpose tool, the Jotunheim 3 is a modular desktop hub. It features a swappable internal DAC card slot — you can run it as a pure amp with your own external DAC, or install one of Schiit's multibit or delta-sigma DAC cards and have an all-in-one unit. There's even a phono stage card option, which makes it a legitimate vinyl-friendly solution.

Power output is generous, with strong current delivery that handles demanding loads — think Audeze planars or 300-ohm Sennheisers — without breaking a sweat. The balanced architecture runs throughout, and the build quality reflects Schiit's reputation for sturdy, unpretentious American manufacturing.

Users who made the jump from the 789 (like the Reddit commenter running the Focal Elex and HD6XX combination) consistently note more presence and authority in the low-end, and a sense of "effortlessness" with demanding material. The Jotunheim 3 doesn't chase the same neutrality crown as the 789 — it has a character, and for many listeners, that character is exactly what they were looking for.

The Trade-offs

The Jotunheim 3 costs noticeably more than the 789, especially once you factor in a DAC card if you want the full integrated experience. If you already own a strong external DAC like the Modius, that modularity becomes less relevant — you're essentially paying a premium for features you won't use.

Listeners who genuinely prefer the clinical, ruler-flat response of the 789 may find the Jotunheim 3 adds a coloration they didn't ask for. It's a subtle thing, but it's real — this is not a "set and forget" transparent amp in the THX sense. Some audiophiles see that as a flaw. Others call it musicality.

Side-by-Side Comparison

Feature	Drop THX AAA 789	Schiit Jotunheim 3
Price	~$220–$250	~$399 (amp only)
Topology	THX AAA solid-state	Fully balanced solid-state
Balanced Output	Yes (XLR + 4.4mm)	Yes (XLR)
Built-in DAC Option	No	Yes (modular card)
Phono Stage Option	No	Yes (modular card)
Sound Signature	Neutral / transparent	Slightly engaging / musical
Best Pairing	Planars, sensitive dynamics	High-impedance dynamics, planars
Upgrade Path	Dead end (single function)	Expandable via Schiit cards
Overall Rating	4/5	4.5/5

Verdict: Who Should Buy What

Buy the Drop THX AAA 789 if you're building your first serious balanced desktop system, already have a strong external DAC you love, and want the absolute best measurements for the money. It's the right call for listeners who prioritize technical transparency and are running efficient, sensitive headphones. Just go in knowing it's a great starting point — not necessarily a forever amp.

Buy the Schiit Jotunheim 3 if you want a system that can grow with you, if you're running demanding cans like the HD6XX, HD800, or Audeze planars, or if you want the flexibility of an all-in-one solution without sacrificing real amplifier quality. The modular DAC system is genuinely useful, and for listeners who've "graduated" from the 789 — as the Reddit upgrade thread demonstrates is a common path — the Jotunheim 3 is a satisfying, long-term landing spot.

The gap in price is real, but so is the gap in versatility. If the budget allows, the Jotunheim 3 is the more mature purchase.

Frequently Asked Questions

Q: Is the Drop THX AAA 789 still worth buying in 2024?

A: Yes, for the price it remains one of the best-measuring balanced amplifiers available. It's an excellent entry point into serious headphone audio, though many users do eventually upgrade to something with more personality or versatility.

Q: Does the Schiit Jotunheim 3 need an external DAC?

A: Not necessarily. You can install one of Schiit's optional DAC cards into its modular slot, making it a fully self-contained unit. If you already own a DAC like the Schiit Modius, you can run it as a pure amplifier instead.

Q: How does the Jotunheim 3 pair with Sennheiser HD6XX headphones?

A: Very well. The HD6XX is a 300-ohm headphone that benefits from amplifiers with strong voltage swing, and the Jotunheim 3 handles it with authority. Reddit users running this exact combination report a satisfying, full-bodied sound.

Q: Can the Drop THX AAA 789 drive planar magnetic headphones?

A: Yes, the 789 delivers enough power for most planar magnetics. It's particularly well-regarded for planars that don't require extreme current delivery.

Q: Is the Schiit Jotunheim 3 worth the price premium over the 789?

A: For most listeners who plan to stay in the hobby long-term, yes. The modular design, better handling of demanding headphones, and the real-world upgrade path documented by community users make it the more future-proof investment.

— Tech Lead Editor 3, CPrice