The setup takes about four minutes. Interface into the USB-C port, guitar into the interface, open Logic, drop an Amp Designer on the track, hit record. Everyone says a modern Mac is a professional guitar rig now, and on paper that is true.
Then you play a chord and it sounds like a wasp in a biscuit tin.
Thin. Buzzy in the top end, hollow in the middle, no weight behind it at all. So you cycle through presets, and they are all bad in slightly different ways. You start reading about which third-party amp plugin is worth the money, on the assumption that the stock one is the problem.
It is almost never the plugin. Guitar tone is a chain, and a recorded tone is the end of a chain that had a specific guitar, a specific input stage, and a specific speaker in it. Change any link and the same settings produce a different result — which is why preset packs and settings lists from records transfer so badly, and why translating a recorded tone onto the gear you actually own is a different job from copying the numbers. On a Mac, three or four links in that chain are set wrong by default, and none of them are the amp model.
Here is the order I would check them in.
1. You are probably plugged into the wrong input
This is the big one, and it is invisible. Most interfaces have a small button marked Inst, Hi-Z, or a guitar icon next to input 1. If it is not engaged, your guitar is going into a line input, and a line input is the wrong shape of hole.
Passive guitar pickups are a high-impedance source. They want to see something around a megohm of input impedance. A line input is typically in the region of ten to twenty kilohms, which loads the pickup down, drops the output level, and rolls the treble off before the signal has got anywhere near a plugin. You end up with something quiet and dull, and then the amp sim amplifies the quiet dull thing.
Press the button. On a lot of setups that single change is most of the problem, and people spend a hundred pounds on plugins instead of finding it.
Active pickups are the exception — they have a buffer built in and are much less fussy. If your guitar takes a 9V battery, this section matters less to you.
2. The plugin is expecting a level you are not giving it
A real amp responds to how hard you hit it. Amp sims model that, which means they have a right answer for input level and you can be well off it in either direction.
Too quiet and the modelled preamp never breaks up, so you compensate with the plugin's gain control and get fizz instead of saturation. Too loud and everything is mush before the tone controls have a say.
Set your interface gain so that hard strumming peaks somewhere around −12 to −6 dBFS on the track meter, and leave headroom. Digital does not have a sweet spot the way tape does; you are not trying to get close to zero. You are trying to arrive at the plugin at roughly the level it was voiced for.
Worth knowing: a lot of factory presets were built around a hot humbucker. If you play a Strat with vintage-output single coils, every preset will feel gainless, and you will overcompensate. That is not you doing it wrong.
3. Buffer size changes how you play, not just how you hear
Latency is discussed as a comfort issue. It is really a performance issue. Above roughly ten milliseconds of round trip you stop playing with the timing you meant to, and you can hear the hesitation on the take even after you have forgotten why it felt awkward.
In Logic, Settings → Audio → I/O Buffer Size. A 128-sample buffer at 48 kHz is about 2.7 ms in each direction, and with converter latency you land somewhere around 6–8 ms round trip. That is comfortably playable. 1024 samples is not, and it is a common default.
Apple Silicon deserves credit here. Recording at 64 or 128 samples with a couple of amp plugins running used to mean crackles and dropouts on an Intel machine. On an M-series Mac it is unremarkable. Track at a low buffer, then raise it before mixing when the plugin count climbs and you no longer care about playing latency.
4. The cabinet is doing most of the work
If you learn one thing about amp sims, make it this: the speaker cabinet is the strongest tone control in the chain, and it is the part people leave on default.
A guitar speaker is not a hi-fi driver. It rolls off hard above about 5 kHz, which is precisely why an amp does not sound like a wasp in a tin in real life. That roll-off is what a cabinet impulse response reproduces. Swapping the IR while leaving every knob untouched will change the sound more than switching amp models does.
If the tone is harsh, the fix is usually the cabinet, the mic model, or the mic position — not the treble knob. Moving a virtual mic from the centre of the cone toward the edge is the single most useful adjustment in most amp plugins, and it is the one nobody touches.
5. One guitar track will never sound like the record
This catches everyone. You get a genuinely good tone, record the part, play it back, and it still sounds small next to a commercial mix.
That is because the commercial mix almost certainly has two performances, panned hard left and right. Not one take copied to a second track — that is phase-identical and just gets louder. Two separate performances of the same part, with the tiny human differences between them, which is where the width comes from.
Record the part twice. Pan them out. The difference is not subtle, and no plugin substitutes for it.
A related trap: a guitar tone that sounds enormous in a finished mix often sounds thin and mid-heavy on its own, because it was carved to leave room for bass and vocals. If you are judging your tone soloed, you are judging it against something that was never recorded.
What about the iPad?
Better than most people expect. A class-compliant interface works over USB-C without drivers, GarageBand for iOS has usable amp models, and AUv3 plugins run inside it. For writing and demos it is genuinely fine.
The same rules apply, with one addition: check what sample rate iOS has actually settled on, because it will quietly follow whatever else is connected. Bluetooth headphones are not an option for tracking — the latency is far past playable, and no amount of buffer adjustment fixes it. Wired, always.
The short version
Engage the instrument input. Set a sane recording level. Drop the buffer to 128 while tracking. Change the cabinet before you touch the EQ. Record it twice.
None of that costs anything, and it will get you closer than another amp plugin will.
Written by the team at ToneMirror.
