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previous: Mark Abbott Firstly, thanks for the replies. I ... -- 1105953347 View Thread

Re: The new tech in town?

1/17/2005 10:05 AM
BWilliamsonRe: The new tech in town?
Thing is, in a situation like that there is no bad publicity. Out of all the members in the group betting most checked the link. Plus how many lurkers checked the link. So welcome or not he's getting his exposure. So I'm all for kicking his butt to the curb!  
 
The article I was thinking of and found is from January 1994. The first paragraph sets it up nicely.  
 
Rosk SBA50 MKI ($975)  
 
Paul Zahorosky was an unkown entity in these parts until he emerged with guns blazing after out December '92 100watt combo amp shootout. Irked by some of our opinions, Paul told us, "Keep your so-called 'expert' evaluations out of your magazine. You're just emphasizing your stupidity." Saving a few hollowpoints for other targets, Paul blasted Kendrick amps as "overpriced hype" and blew away Crate as "obvious garbage." Referring to his own amps, Zahorosky crowed, "My top-of-the-line 50watt head blows those Kendrick and Rivera amps out of the water, performance- and price-wise. When you guys are ready to evaluate a real tube amp, let me know." Boy, the things people will do for attention. We're always suckers for something new, though, so we requested a Rosk for review. "I don't send anything our for free," snarled Zahorosky. "If you want one, you're going to have to buy it." So, we sent a check. Paul promptly returned it, explaining the price had gone up $10 (hey, every little bit counts). We sent out another check, and bingo! Nearly a grand later, here sits our shiny new SBA 50.  
 
Rest of the article isn't too bad, gave it good marks for high quality components. This is kinda funny:  
 
To call the SBA's guts highly original is an understatement; a corkscrew wire glopped with silicon extends from a small transformer near the center fo the chassis, there are trimpots a-plenty, wires disappear into a little metal box epoxied to the chassis. The SBA even cops our coveted "Most Silicon Seal" award for the extensive us of the stuff on just about everything. (Zahorosky points out that silicon is an excellent insulator, shock mount, and staking compound.)  
 
H.A.D. had an admirer in more ways than one--read on:  
 
Another quirk: Before we received this amp, I was asked to sign a document (as are all Rosk purchasers) that stated, in effect, I would not let a tech look inside this amp for any reason unless I obtained prior wretten permission from Rosk.  
 
They go on to ask about, what if the Rosk craps at the Hang'em High Casino in Pahrump, Nevada. His quote is, "I've never had an amp come back for repair".  
 
The article goes on to talk about the very thorough 13 page manual and 3 pages of quick setup material. Settin some "Positive Feedback Control" thingie and then goes on to talk about the performance. They don't really go on to say anything one way or another good or bad about the tone, clean or dirty. But get's interesting here:  
 
Our testing was cut short when on of the Rosk's EL34s suddenly began to glow bright orange. Fearing immediate tube destructtion, we shut the amp down, replaced the tubes, and continued. Now here's where it gets weird: We had been hearing a arcing sound whenever the amp was placed on standby, but were unable to determine the cause. The SBA also thumped very loudly whenever standby was selected. Looking inside, we observed occasional flashes of light from the the interior of the volume pot (the only control that isn't a sealed type), and our meter indicated that over 400 volts was present on one side of the control. Holy shit! Is the Rosk amp a Trojan horse sent to kill unsuspecting editors, you ask? According to Zahorosky, no. Paul didn't want us to spill the beans about this part of his circuit design, but he said, "The control will be replaced by a sealed Clarostat dual pot on future amps. The 400 volts you measured is caused by a defective pot and is definitely not correct."  
 
Rosk strives to keep you ouf of harm's way by modifying the plastic knobs set screw so it can't be easily removed (it's the only one altered this way-hmm). However, the pots shaft is metal. If that knob came off and you happened to grab the bare shaft while touching a ground point, you could be playing pinochle with the Big Man in a wink. (Paul disagrees, saying, "As to someone getting a shock, all the pot shafts are grounded to the chassis and it would be impossible for a shock to occur unless someone defeats the earth ground-a stupid ting to do!") I wonder what Underwriters Laboratories would have to say about this.
 
 
My opinion here: Most musicians I seem to run into don't have a clue about anything gear related--either they like it or they don't and would defeat a ground in a heartbeat.  
 
We continued to have trouble with the Rosk burning ouput tubes--even after swtiching to a different brand of EL34s. Zahorosky told us that if the amp needed service, he'd turn it around in 24 hours-same for all his customers-so we're shipping teh SBA back to get these problems checked out. (By the way, Rosk's warranty extend for a mondo 15 years!) If there's anyting new to report we'll let you know. -end  
 
As I recall when this article came out, I watched for any followups and didn't see one. Could have missed it though, but from here Rosk seems to have disappeared off the map. Find it strange that none of the HC fanboys haven't reviewed anyting by him, find no entries under Rosk or Zahorosky in the amp section and they seem to review everyting if they own it or not.  
 
My previous post my memory was faultly as there was no second amp sent to replace. Must have got that mixed up with something else.  
 
Anyway, draw your own conclusion. Myself, did consider checking out one of his offerings as I'm always looking for some new tidbit of information or to hear somebody's angle on something but after digging this article out and rereading it I'll pass.  
 
bw

 
Replies:
neil I certainly understand keeping comm... -- 1/17/2005 2:01 PM
Paul Rosk Kick my butt into the curb?... -- 1/19/2005 8:41 PM