Sonaro question - weirdness abounds

[EdBass]

There is something strange going on with your SVT. Preamp tubes can normally last several years, even decades, even with hard use.
 

[JoeArthur]

There is something strange going on with your SVT. Preamp tubes can normally last several years, even decades, even with hard use.
 

+1.

[basiklybass]

There "WAS" something strange going on with it...haven't had it for many, many years.....Oh no....yep...it really was 30 years ago...dang...I'm getting a bit old.

Just a bit though.

[mratcliffe]

You said that this was labeled as a 190B but the sticker was peeled back? Interesting. Did they also do this on Sorados and 200s as well?

[urbanspaceman]

Ok, so I've tried it out at a few practices and the strange noises return once the amp has been on for a while and the tubes are good and hot. Looks like I'll have to replace them. My bandmates have insisted that I not try the KT-88's for fear of their eardrums, and worries that this may alter the sound too much - it has a really sweet growl to it right now.

Any suggestions on a good set of 6550's?

I still don't believe that this is a 60 watt amp. While it was in the shop, I used a '68 silvertone guitar head (really clean sound and a cool spring reverb) to power my speaker cabinet. It is  rated at 100watts. Absolutely, no comparison. The sunno)) blows the doors off it.

[mratcliffe]

My Sonaro also makes strange sounds. I also have a 1970 2 (6550). Mine makes a clicking sound. I cannot locate where this is comming from. I think it is one of the 6550 but I just can't swear to it.

[mckinnon audio]

 Hi,the clicking you hear is probably arcing going on. Could be a cap,tube,or a cracked carbon resistor. Maybe a tube socket to ground.Pull the tubes and see if the click returns when powered up,if it doesn't try another set of outputs. If it's still there,it's not the tubes.Be careful there's a few volts in there. Good luck Mel.

[Soundmasterg]

KT 88's will be a little louder than 6550's but not so your bandmates would notice. Good 6550's would be the Winged C 6550C, or the Tung-Sol reissue 6550. Personally I'd use the JJ KT88, but the others will work and sound fine too.

That Silvertone that you played.....what were the power tube complement? If it was two 6L6GC, then it is a 25 watt amp (Silvertone 1484) . If it is four 6L6GC, each one having it's own output transformer, then it is a 50 watt amp, (Silvertone 1485). The power rating that they stick on the back of amps is the amount of power it draws from the wall voltage. They never put the power output on the back of amps, so anything you read off the amp itself is not actually the power output.

The Sunn Sonaro/200S is a 60W RMS amp, with JJ KT88's it will be 70W RMS. You could get higher power by disconnecting the UL circuit and having a bit more plate voltage, but then its a different amp. A pair of 6550/KT88 can make as much as 100W RMS with the right voltages and transformers, but none of the Sunns were that high off only 2 power tubes. Their 4 power tube amps like the 2000S or Model T are 120W RMS amps and are freaking loud. The transformers are also as big as your head too.....


Mratcliffe, the clicking that you're talking about could be arcing, or it could also be an oscillation too. Could be a bad part like a cap, resistor, or transformer, or it could be a layout issue with wiring. It requires some troubleshooting, but Mel's suggestions are a great first step.

greg

[JoeArthur]

That Silvertone that you played.....what were the power tube complement? If it was two 6L6GC, then it is a 25 watt amp (Silvertone 1484) . If it is four 6L6GC, each one having it's own output transformer, then it is a 50 watt amp, (Silvertone 1485). The power rating that they stick on the back of amps is the amount of power it draws from the wall voltage. They never put the power output on the back of amps, so anything you read off the amp itself is not actually the power output.

The Silvertone twin-twelve piggy-back is a pretty neat amp.

Of course, Silvertone also made solid-state amps rated up to 100 watts which tube bigots might not know about!! 

[Soundmasterg]

Yah those twin twelve Silvertones are pretty cool. Stock they sound good, and modded they sound better, but either way they are a PITA to work on and have a very poor layout. Increase the gain too much and the poor layout becomes a huge factor. What idiot designer puts the power transformer in the middle of the chassis because it will be easier to carry that way?!!! But I digress.....

[basiklybass]

I haven't heard a Silvertone since....hmmm...1971 or maybe 2.

I do remember that it sounded like crap next to the Fenders, Ampegs, and other amps we had. The construction was terrible, wiring had cold solder joints, eveything was loose...and the Tolex....was like wrapping paper. Even the speaker baskets were lightweight......I do think it was a twin 12.

Guess it's all in our heads, eh?

[Soundmasterg]

MOst of the Silvertones sound good in a lo-fi kind of way. Its a useful sound...just listen to the White Stripes. They take to pedals really well stock and sound great with off brand guitars or stuff with weaker pickups like a Jazzmaster or a Rickenbacker. Their construction is pretty lousy, though it is often PTP with the components leads wrapped around terminals, which is a good thing. They aren't a Fender, Ampeg, etc, so you just have to not expect them to be and just use them as they are. Their reverbs are some of the worst I've ever heard though. Their trem is nice.

[basiklybass]

Like I said in the other post, I need to play better and be less concerned about how my amp sounds. If Jack Bruce walked into my basement...I am sure he would make my Aria bass and my old beatup SWR Workingman's 10 would sound like the best thing ever heard. One of the best bassest I have heard was in a small club in New Hampshire playing a Squire P bass and a recent Fender Bassman 200. I have played Bassmen recently and did not like them at all. This guy made it sound deep and full and still have cut-through ability and presence. Nope, don't even remember the name of the band

It's just weird to think that stuff we had back then...is so valuable now. Did you see that beautiful 200S go for over $2.3K?

[Soundmasterg]

2.3k? No thats an insane price but maybe I'll sell some of my amps if they're selling for that! Geez!!