New (Old) Amp Day: Sound City 100

[WhiteNinja]

Hey all!

So, I just required this old Sound City amp for a very nice price. It's an L100 Mark 3 Custom Built from 1969. I originally bought it for guitar, but since I don't have a decent guitar cab to use it on atm (still on the lookout), I thought I'd give it a whirl with my Ampeg 810 cab in the meantime. To my surprise it sounds REALLY good. Loud and raw, very vintagey, goes really loud before it breaks up. It doesn't have the thunderous low-end as the SVT or other all-tube bass amps, but it has it's own character that sounds sweet.

I really want to try it in a band context now to see how it holds up compared to the SVT. Maybe I could use the Rick-O-Sound on my 4001 to run BOTH amps at the same time, with the SC set to overdrive!

Any other guys here who have a Sound City amp, or use an old guitar amp for bass? Anyone want to share some info about the Sound City amps? I don't know too much about these, other than they are similar to Hiwatt, apparently.

Here's a pic of it sitting on my 810:

[coreyfyfe]

Congrats on the amp! I recently picked one up as well, a 75 Mk 4 L120 amp. Amazingly loud and clear. Just went through the process of recapping and cleaning mine up (album of pics here). I used mine at a gig the night it arrived and it was pretty awesome, albeit a bit noisy (given the state it was it, no surprise really). Either way, enjoy yours, they're pretty nice little amps!

[Downunderwonder]

Originally Posted by WhiteNinja

Hey all!

So, I just required this old Sound City amp for a very nice price. It's an L100 Mark 3 Custom Built from 1969.

I require you to send it to me.

[GreaserMatt]

^^^ LOL!!! I'm not sure which one to drool all over first; the head or the cab! Talk about a dream rig... I love that kind of stuff though...

[bertbass666]

A MK3 walks all over a MK4 in my opinion. Used them a lot in the late 60s early 70s. Great amps. If you need more bottom end just stick a graphic EQ in front.

[WhiteNinja]

Originally Posted by coreyfyfe

Congrats on the amp! I recently picked one up as well, a 75 Mk 4 L120 amp. Amazingly loud and clear. Just went through the process of recapping and cleaning mine up (album of pics here). I used mine at a gig the night it arrived and it was pretty awesome, albeit a bit noisy (given the state it was it, no surprise really). Either way, enjoy yours, they're pretty nice little amps!

*pic*

Awesome, love that cab and the way it looks... it definitely has a story or two to tell! Great stuff!

Originally Posted by Downunderwonder

I require you to send it to me.

Aquire, of course, silly me! Your request has been denied, though!

Originally Posted by bertbass666

A MK3 walks all over a MK4 in my opinion. Used them a lot in the late 60s early 70s. Great amps. If you need more bottom end just stick a graphic EQ in front.

How is a MK3 better than a MK4? Genuine question; I don't know too much about these, other than the association with Hiwatt... and that they sound awesome!

I don't use a graphic EQ, but I have a Phat Phuk B booster that gives me the bottom end that it lacks by itself, really makes it sound BIG.

[coreyfyfe]

Originally Posted by WhiteNinja

How is a MK3 better than a MK4? Genuine question; I don't know too much about these, other than the association with Hiwatt... and that they sound awesome!

The Mk3 and older were a simpler design. The Mk4 introduced an active pre-amp that can be a bit noisy and very sensitive to small changes so a lot of people don't like them. Running it clean, I don't feel like there's as much difference as if you're really cranking the amp. The 120's are loud as all get out before you get any distortion, helps that they have 6 EL34s.

[WhiteNinja]

Tried the amp at the rehearsal room tonight, and it was awesome. Really nice, middy vintage tone, with enough balls to make the whole room shake!
It totally slayed with a fuzz though. Damn, what a sound. Wish I had a recorded it, it was really fun.

There's just something about those old tube monsters... I don't think I could go back to SS stuff ever again. That view might change with me getting older though, who knows. :P

Originally Posted by coreyfyfe

The Mk3 and older were a simpler design. The Mk4 introduced an active pre-amp that can be a bit noisy and very sensitive to small changes so a lot of people don't like them. Running it clean, I don't feel like there's as much difference as if you're really cranking the amp. The 120's are loud as all get out before you get any distortion, helps that they have 6 EL34s.

Interesting. Didn't know about the active EQ thing. Was that an original design by Sound City?

[Mr. Foxen]

The Mark 4 active eq seems fairly unique to sound Scity as far as musical instrument amps go, like most things it probably came from a book. It is a pretty good eq, you just have to make sure it isn't broken. Because it has tons of gain, but not distortion, some noise gets quite loud, so you need to sort the noise, mostly from degrading carbon composite resistors, replace them with new ones. A full recap is as necessary as it is with any amp of that age too. Once that is done, absolute monsters, but for people used to setting passive valve amp eqs by eye, where you spin the knobs like a safe dial, it causes trouble.
Edit: thread on sorting a mark 4 Sound City B120 MKIV restoration

[godofthunder59]

I have a SC 200 Plus great amp paid 149 for it.

[WhiteNinja]

Originally Posted by godofthunder59

I have a SC 200 Plus great amp paid 149 for it.

Nice, how's that working for you? Is it similar to the Hiwatt Custom 200?