 Hello everyone and welcome to Blackstar Potential. My name is Lee Fuge and I'm here with MGRMusic.com and today we're going to look at another Blackstar patent. This week we're going to check out the ISF. ISF stands for Infinite Shape Feature. This is a patented feature built into a lot of Blackstar amps so if your amp has this feature all of the principles we talk about in this video will apply to you. The amp I'm going to be demonstrating this feature on is the HT20 Mark II but the ISF is available on a lot of the Blackstar range. On the top panel of the HT20 Mark II we've got the overdrive equalization section. This contains bass, middle and treble as you typically expect to see on most guitar amplifiers. Then we've also got the ISF. The ISF works by shifting the whole tone stack response so when you move this control these three controls react slightly differently. We can break the ISF down in a nutshell in two main positions. If I set it all the way to zero this is the American position. This gives you a tight focused but cussive sound like all your favorite American amps and if I push this all the way around to 10 this will be more of a British voice. This is a warmer, woodier sound with a bit more of a mid-range crunch. We can blend these two sounds anywhere we want in the middle to create the best of both worlds. The ISF feature allows us to bypass the tonal limitations of specific amplifiers. The reason most big amplifier companies have their own specific sound is they use a variety of component values across the tone stack to give snapshots of what that EQ band can do. These signature sounds are limited by the fact that they are just a snapshot of the full tone spectrum. Because the ISF shifts the tone stack depending on where we set it we can actually recreate the snapshots of any brand we want but we can also blend them in the middle so we can create new tones that we've never heard before. It's a completely passive circuit and the ISF is very reactive with the existing three-band EQ built into the amp. So when it's set to the American side the bass middle and treble frequencies react more like an American amp and on the British side they react more like a British amp. In the middle we get this nice blend of the two. This is where you can start to create the sound in your head. So first of all let's take a look at how the ISF affects each of the bands. So currently I've got a very mild overdrive dialed in. I'm going to leave the EQ flat and I've got the ISF all the way in the American position. If I now push that all the way over to the British side we're going to get a slightly different tone response. And if I set that in the middle I'm going to get the best of both worlds. So like I said this also reacts with the three-band EQ so let's take a look at that. So start by turning the bass up to 10 and leaving the ISF in the American side. The British side we'll do the same with the mid control now so turn the mid up full and push the ISF all the way to the American side. And the same with the treble so push that all the way up and push the ISF to the American side. All right now that you know what the ISF does let's look at it from the perspective of a few classic tones. So for this I'm just going to keep the EQ pretty straight unless I need to tweak it for any reason so it's just going to stay everything up at 12 o'clock. I've got the overdrive quite low for the first tone and the ISF all the way to the American side. Coupled with a telecaster style guitar this is going to get us a pretty good Rolling Stones type rock tone. But if I now move the ISF all the way to the British side I'm going to get something in the ballpark of an early Led Zeppelin style tone because on the first Zeppelin album Jimmy Page used the telecaster. Now let's see how it reacts with humbuckers. So if I go straight back to the American side keep the gain nice and low I'm going to get a really great low gain bluesy American breakup tone. If we flip the ISF all the way to the British side we get a much more British kind of blues tone think 1960s British blues invasion. So you can dial in all of your favorite British and American blues tones there just by adjusting the ISF. I'm going to push the gain just a little bit more now and I'm going to bring the volume down just a touch. This is going to get us into a bit more of a classic rock ballpark so you think like your Led Zeppelins and your Aerosmiths all those big classic rock bands that had the big British guitar sound. If you want to go a bit heavier we can do that too. I'm going to bump the gain just a little bit more to about halfway and I'm going to push the ISF all the way to the American side. I'm going to bring the mids down to about three because now we're going to do a scooped American metal tone. So think of your early Metallica kind of tones that nice mid scooped punchy heavy thrash tone. We can go straight from heavy American thrash to British 80s metal so just push the ISF all the way back to the British side and bring those mids back in and we're straight into your sort of 80s Iron Maiden or Judas Priest kind of tones. So there you go there is a tonal journey through the ISF feature with a bunch of riffs that you can use as a reference point. Now that you know what the ISF does if you have one on your amp you can really start to dive in tweak all these tones and create the sound that's in your head. I gave a bunch of demonstrations there from extreme American to extreme British tones but if you like any of those tones you can play with the ISF and blend the best of both worlds in your own creations. Thank you all so much for watching I hope you've enjoyed this video and I hope you've enjoyed this Walkthrough the ISF feature. Don't forget to check out Blackstar Amps on YouTube for more video lessons just like this. We cover a bunch of other stuff from famous artist tones to other Blackstar patents and interesting ways you guys can use your Blackstar products to create the sound in your head. Let us know down below in the comments if there's any artists you want us to talk about the tones of or anything else you want us to cover to do with your Blackstar amp. If you're looking for a guitar teacher in your local area please check out MGRmusic.com we've got a network of great teachers all over the UK just waiting to help you guys release your full potential. Thanks for watching and we'll see you soon.