Both are audio interfaces, $299 against $199. This page puts them side by side on the only three things a maker can be held to — power, output impedance and noise — and then asks the question that actually matters: which headphones do they treat differently?
The PreSonus Studio 68c reaches 100 dB on 558 of the 567 models here, the Tascam US-2x2HR on 541.
| Specification | PreSonus Studio 68c | Tascam US-2x2HR |
|---|---|---|
| Power into 32Ω | 86 mW | 18 mW |
| Power into 150Ω | 56 mW | 17 mW |
| Power into 300Ω | 28 mW | 12 mW |
| Power into 600Ω | 14 mW | 7.3 mW |
| Output impedance | not published | 66 Ω |
| Output noise | not published | not published |
| Price | $299 | $199 |
| Headphones it reaches 100 dB on out of 567 | 558 | 541 |
A figure marked not published is missing from the maker’s own material, which is not the same as being good or bad. Where one of these two publishes a number and the other does not, the comparison on that axis cannot be made at all — and saying so is more useful than guessing.
| Load | PreSonus Studio 68c | Tascam US-2x2HR |
|---|---|---|
| 32 Ω | Derived | Published |
| 150 Ω | Derived | Derived |
| 300 Ω | Derived | Derived |
| 600 Ω | Derived | Derived |
Only one of these two columns starts from a power rating. Tascam US-2x2HR publishes one at 32 Ω; PreSonus Studio 68c publishes none at any of these four loads, so its column is worked out from power it published at other loads. Both are arithmetic on a maker’s own figures rather than guesses, and the method used for the PreSonus Studio 68c understates rather than flatters — but at 32 Ω is the only load here at which its maker can be held to a figure.
What each of these labels means, and why a derived figure is still worth printing, is set out in how this data was built.
17 headphones reach 100 dB on the PreSonus Studio 68c but not on the Tascam US-2x2HR — Abyss AB-1266 Phi TC, Audeze LCD-5, Dan Clark Audio AEON 2 Closed, 14 more.
541 of the 567 models here reach 100 dB on both. That is a power count and nothing more; whether either source suits a given headphone also depends on the two lines above.
The counts above say how many models the two treat differently. This says by how much. The same 8 headphones appear on every page of this kind, ordered from the easiest to drive to the hardest, so a row can be read across pages as well as across columns. Headroom is at a 100 dB SPL peak.
The widest gap on the list is the HiFiMAN Susvara: PreSonus Studio 68c has +4 dB of headroom there against -5 dB. 10 dB is about 9.1 times the power, which matters for peaks rather than for how loud the music sits.
The hiss columns are empty for PreSonus Studio 68c and Tascam US-2x2HR because neither maker publishes no output noise figure. That is a gap in the specification, not a quiet amplifier, and it is left blank here rather than filled with a plausible number.
| Headphone | Impedance | Needs | PreSonus Studio 68c headroom | Tascam US-2x2HR headroom | PreSonus Studio 68c hiss | Tascam US-2x2HR hiss |
|---|---|---|---|---|---|---|
| Shure SE846 | 9 Ω | 0.04 mW | +28 dB | +21 dB damping | not published | not published |
| Campfire Audio Andromeda 2020 | 9 Ω | 4.0 mW | +8 dB | +1 dB damping | not published | not published |
| Audeze LCD-2 Classic | 70 Ω | 0.79 mW | +22 dB | +13 dB damping | not published | not published |
| Beyerdynamic DT 1990 Pro (250Ω) | 250 Ω | 0.63 mW | +17 dB | +13 dB damping | not published | not published |
| HiFiMAN HE400se | 25 Ω | 7.9 mW | +9 dB | +2 dB damping | not published | not published |
| Audio-Technica ATH-R70X | 470 Ω | 1.6 mW | +11 dB | +7 dB damping | not published | not published |
| Sennheiser HD 600 | 300 Ω | 6.6 mW | +6 dB | +3 dB damping | not published | not published |
| HiFiMAN Susvara | 60 Ω | 50 mW | +4 dB | -5 dB damping | not published | not published |
The PreSonus Studio 68c costs $100 more than the Tascam US-2x2HR. Out of the 567 models here, that difference buys 17 more models driven to 100 dB.
Nothing runs the other way: there is no axis here on which the cheaper of the two does better.
Everything in this paragraph counts only figures the two makers published. An advantage on an axis one of them leaves blank cannot be counted, and is not counted — how often that happens is its own page.
Each has a page of its own with every power figure traced to what the maker published and a full headphone list: PreSonus Studio 68c and Tascam US-2x2HR. Or put either against your own headphones in the source comparison tool.