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Dynaco SCA-35 or Sherwood S5000 iV

jscherer

Member
2008-04-07 8:51 pm
I can get ether one of these amps at a good price ( <200), both in need of some restoration work and would love to hear from you guys as to which of the two would be the smarter choice.

I'm leaning towards the Sherwood but seeing that I'm new to tube amps in general, I don't want to make an uninformed decision.

Thanks

John
 
For a new-be tu-be (sorry, Mr Eisenson) It seems to me that the SCA-35 would be more practical unit. As I recall, the later Sherwood S5000, used 7591 output tubes which are no longer in production. While still fairly common at the this time, supplies will undoubtedly be more difficult to find in the future. The Dynaco uses both the 12AX7 and EL84 in it's circuit, both easily obtainable, since they are currently produced by numerous manufacturers.

Parts and information are plentiful for the Dynaco, but less so for the Sherwood. The Dynaco OTs are excellent--another strong plus in it's favor. It's weak points are the "crappy" quality circuit boards (I think someone is making new ones), a marginal preamp section (which can be improved with a little work), and a hot running power transformer which fails easily.

There's another forum that has quite a bit of information on the SCA-35:

http://www.diytube.com/phpBB2/viewforum.php?f=1
 
I'm wrong about the 12AX7! It's a 7199-pentode single phono stage for high gain, with the triode section used as used as a concertina phase splitter. Looks like the accountants won that battle! As I said, it's not a great setup, and a number of people have found ways to improve upon it. I should have said, "It should have a 12AX7".
 
Re: Dynaco SCS-35 or Sherwood S5000 iV

jscherer said:
I can get ether one of these amps at a good price ( <200), both in need of some restoration work and would love to hear from you guys as to which of the two would be the smarter choice.

I'm leaning towards the Sherwood but seeing that I'm new to tube amps in general, I don't want to make an uninformed decision.

Thanks

John

If it were me, I would go with the Sherwood. I think the Sherwood S5000/S5500 line can sound excellent with some restoration work, and I think the build quality is nicer than the Dynaco also. Don't discount the Sherwoods iron, it has very hefty transformers that sound excellent. I would look to see which tubes you would get with each amp, as getting the tubes with the Sherwood would be a definite plus.
 
ArtG said:
I'm wrong about the 12AX7! It's a 7199-pentode single phono stage for high gain

SCA35 has a 12AX7 per channel for the phono stage and a 7199 for the front end of the power amp.

I've not seen a Sherwood, but have had quite a few SCA35. If you want an amp to restore/keep the retro flavour then probably the Sherwood. If you want a donor amp, either would probably do.

SCA35 OPTs have UL taps, Sherwood doesn't (not an issue if you triode strap the EL84s).

As far as output tubes for the Sherwood, you can get Russian EL84M fairly easy. Or you could use the high B+ as an excuse for an extra LC or RC stage in the power supply.

The SCA35 would need a new chassis to do much to it... a separate filament trafo will help the power transformer weakness (i'm using 1 SCA35 power trafo per channel in my project.

dave
 

jon_010101

Member
2005-11-03 4:44 am
Regardless of what tubes the Sherwood has (might be 7868 even?), it is going to be a better amp than the Dynaco, but just a bit harder to restore. I have one right now on my to-do list, and I expect good things. The Sherwood's preamp stage with active tone controls is a real bonus, vs. the passive Dynaco tone controls. And the chassis is really quite a step up, with point-to-point wiring vs. crunchy old circuit boards.

In summary, the Dynaco wouldn't disappoint, but the Sherwood is more likely to impress. :D
 

kevinkr

Administrator
Paid Member
I think it depends a lot on your skill set, if you have some experience working with point to point in tight spaces then the Sherwood would definitely be the route I would pick.

OTOH if you are a total newb there is more information and a lot of replacement parts available for the SCA-35. IMHO The stock SCA-35 is relatively mediocre at best, however the iron is very good. (Good for heavy modding.) The chassis and pcb are pretty low rent however..