I've mainly been a Line 6 user for the last 8 years when it comes to guitar amps/fx. I've also tested out Amplitube 1/2 and GR2/3, but although they both had their strengths and were great in places, they didn't make me want to part with my money. TH1 on the other hand made me sit up and take notice as soon as I loaded up the demo and it wasn't long before I had bought it. It felt like a step-up across the board.
It's got a great collection of amps, rack fx and stomps - they are mostly modelled on real-life products but that's not shouted from the rooftops like it is in rival products. It's almost liberating to get away from that and just concentrate on creating the tone that is in your head, rather than trying to collection every virtual vintage pedal going! This is reinforced with features such as SLR, which lets you morph between amp models so you truly are creating your own sound. Mix a clean Fender-ish amp, with touch of a Marshall-ish amp and you give the amp a shimmering sound with a bit more bite. The possibilities here are endless.
I'm still to explore all the options, but using the amp which I believe is based on a Fender Twin Reverb I can get shimmering clean sounds. I've found pretty good clean tones before but when I compare them to these ones they seem a bit dull in comparison. Stick one of the overdrive pedals in front of the amp and you've instantly got great dirty tones with a bit of bite. Distorted tones are great too with the more modern amps, and I'm especially impressed with the dynamics you can get - palm muting sounds so much better with TH1 than other amp modellers. There is a range of great FX to create your tone and these will expand with future updates (such as the forthcoming 1.1 update). Add to this numerous cab and mic options (the mics are moveable in 3D around the cab and you can mix two together) and the ability to use the mixer to combine two different setups and pan and mix however you want - you can get seriously deep in creating the tone you are after. A special mention should also go to the reverbs in this, which come from Overloud's other big product - Breverb. They are probably the best reverbs I've heard in software and I'm sure they make a big contribution to the way this thing sounds.
The GUI is one of the things that really drew me to TH1 before I'd even heard it. It looked really intuitive and it is. Much more so than the way GR3 or A2 are designed. You build your rig just as you would in real life. It's all so easy - just drag and drop. Copy parts of your rig and paste into another channel. Swap parts around with one click and drag. It's a great way to quickly get going when you load up the software. The code seems rock solid too and works perfectly in ultra low latency. I've had no crashes running in standalone mode or as a VST. CPU usage is also very low - almost laughably so. Run a dual rig with loads of fx and on my Core 2 Duo it’s generally using around 3-4%!
A mention should also go to the control options. At the bottom of the screen you can set up your own switches, knobs or tap controls and with a couple of clicks you can link it to a dial or switch on one of the amps or fx’s. You can also easily dial in ranges (mix/max) and curves of each parameter. These can then be activated either with a click of a mouse (or using the scroll wheel) or via MIDI CC to link them up with an external controller. Some of the presets also shows how deep this can all get, with one button press switching multiple settings which activate another part of the rig and change the pan and level controls in the mixer. Awesome stuff.
So, what about negatives. I can't say there are any big ones - noise gates are currently universal and not saved per patch. However a noise gate pedal is being released next month which will remedy this. I'm not massively keen on the way the preset browser works - I can't put my finger on what exactly but it doesn't feel quite as intuitive as it could. If anything that's released me to create my own patches which can only be a good thing. I’d also say the documentation is a bit weak in that it presumes you know about each of the modelled amps/fx and how to use them. I’ve had to a bit of my own research to find out, for example what the differences with the overdrive pedals. Maybe I should just use my ears, but I do like to have some idea in my head what each one is best for so I can dive straight in. As I said, none of these are major negatives and none take anything away from how good this product sounds!
I would definitely recommend anyone who's in the market for a new amp sim (or currently using a rival one) to pick this up and give it a go. Things can only get better with the next update (2 more amps, more rack/stomp fx, more advanced routing options and most importantly you can use impulses!). I've also yet to explore using this on things other than guitar. Stick a bit of chorus and (b)reverb on a vocal and it would sound sweet. All hail TH1!