Re: H&K 5 watt OR Blackstar HT-5 head for my Randall 4 X 12 cab....
Do you plan to use it to play with other people? Or to practice at home? I'm going to have to advise against it in either scenario, lol.
I have a Randall RD5 combo that I can plug into my Marshall 4x12. Even though the 4x12 has two efficient Vintage 30's, the 5-Watt Randall is nowhere near loud enough to jam with a loud, busy rock band with a heavy-hitting drummer even if you crank the volume to 10, IME. Now let's say the drummer hits his drums moderately and it's a smaller band: you still have to turn the amp's volume pretty high, and, at that point, these amps don't sound their best. If you're going for the "amp on the verge of meltdown" kind of tone, I guess it's ok, but even the thinner low-end a tiny 5-watt power section can put out is farting out at this level. And forget about cleans, which is a big deal since you plan on using processors and pedals... and then again, if you're going for that kind of brown sound, you're probably not the kind of dude who likes the sound of drummers to hit their drums like they're afraid to ruin their manicure.
For bedroom or home jamming by yourself or with a couple of other guitarist dudes... I mean, 5 watts at low volume barely tickle the speakers on a 4x12, so expect slighly fizzy, stiff kind of tones... at least compared to a full-on 50 or 100watt amp. I mean, even if you're going to be using the amp mostly for recording, this is going to be the case, which might or might not be workable, depending on what kind of tone you're going for and the style of music you play.
So... honestly, I hate to be a naysayer, but I'm going to have to.
