Vintage Asylum

Classic gear from yesteryear; vintage audio standing the test of time.

Return to Vintage Asylum


Message Sort: Post Order or Asylum Reverse Threaded

Which tube integrated to keep forever? Pilot or Sherwood?

76.64.63.119

Posted on December 2, 2014 at 17:04:13
goofytwoshoes
Audiophile

Posts: 751
Location: Ottawa
Joined: December 20, 2003
Time to sort out which tube amp to keep long-term. Currently have a Pilot 245A (EL84 output tubes), a Sherwood S5000 (7189 tubes), and one mono Sherwood S1000 II (4 EL84 tubes, for 36 watts output). The Pilot and Sherwood S5000 are both working, but have been used only sporadically, and I like them both. I've never powered up the S1000. Would buy another S1000 for stereo if sound quality would be as good as the S5000. Current daily driver is an Akai M8 reel-to-reel. This has mono integrated tube amps (with phono inputs), using EL84 tubes in SEP mode for 6 watts output, and is staying forever, too - if it had more power I'd not keep any of the others.

My plan is to have the keeper rebuilt, and to sell the others to pay for the rebuild. Would like to hear your thoughts as to which is likely the keeper (bearing in mind that playing vinyl is important). Also, any recommendations as to where to get the rebuild done, preferably in Canada?

 

Hide full thread outline!
    ...
RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 2, 2014 at 17:49:30
Eli Duttman
Audiophile

Posts: 10455
Location: Monroe Township, NJ
Joined: March 31, 2000



Where in Canada is easy. Communicate with Don Sachs who posts as dls123.

FWIW, I'm inclined to say rebuild the Sherwood S5000. L_RD knows enough "inmates" drool over that item.

You said "vinyl" is very important. Rework things to hard wire a single set of RCA I/Ps to the phono section, as switches in mV. level signal lines are NOT a good thing. If that means a new rotary source selector switch, so be it. A nice Lorlin part costs less than 5 USD. :>D Also, altering the phono section to use tweaked RCA topology (schematic uploaded) is something to consider.


Eli D.

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 2, 2014 at 17:56:52
Keep the Pilot and sell me The Sherwood.......

Do you have pics of both?










 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 2, 2014 at 17:57:32
DaveV
Audiophile

Posts: 513
Location: SC
Joined: December 26, 2009
If I had those units I'd be looking for opinions on what to keep too.
The 36 watt mono Sherwood obviously has it's merits and the Pilot looks to have some nice sized xfmrs.
I've never heard an S1000 or Pilot 245A but I have an early S5000 with the slopped 12AX7 mount behind the front panel and it's a real keeper for me.
Even in it's original state, other than the output coupling caps so far, it easily betters the rebuilt Scott 299A I still have and the Fisher 400 and 500C I once had, minus the built in FM of course.
I find the phono gain to be enough for the many MM/MI cartridges I have including a lower output Grado Signature MCZ5.
The original selenium rectifier is going and the low voltage supply is sagging so I stopped using it until I do a partial rebuild because the 7189's are at risk of being toast without enough negative bias voltage.

What's amazing to me is that it sounds like a an amplifier that's 30 to 40 watts per channel even with the original PS lytics.
I've been so happy with the S5000 I may sell off my Mac C-22 and one of my MC225's to fund other projects around the house.
I can listen to the Mac stuff with my Altec Model 19's but the S5000 and my 3 way EV Esquire 200 bookself speakers are a terrific combo that sound more natural and warm to me in many ways than the more sterile sounding Mac/Altec combo and the Mac stuff with the EV's is just OK to me. Go figure.

If your looking for someone in Canada, then check out the provided link.
In an earlier S5000 thread, Don provided a pic of his work on an S5000.
In the states Michael Samra has a good reputation and pics of his work are in that same thread.

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 2, 2014 at 19:27:21
Michael Samra
Dealer

Posts: 36118
Location: saginaw michigan
Joined: January 30, 2005
Hi there
I just bought another S-1000 30 miles from me and I have three so I may sell one...They are fantastic when rebuilt.
The S5000 is an integrated stereo amp that has no equal after it's rebuilt AFAIC. I am talking within its power rating of course but the execution of that amp is absolutely brilliant...It has a ultra linear output transformers and a five tube preamp with a Mullard driver stage and has copper internal lining in the chassis.
The S-1000 is also ultra linear and it has copper shielding on the power transformer along with similar chassis metals to the S-5000.
If you need 36 watts,the S-1000 is your amp if you score a second one. It also has the benefit of being a separate amp with its own power supply.
The Sherwoods are the keepers and I would sell the Pilot.The Pilot does not have the iron of the Sherwood and even tho it's a nice amp,it's no Sherwood.Let me clarify...Pilot builds fantastic amp and preamp separates which are first rate..Sherwood built nothing but integrated amps and receivers and they are good at it.

"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken

 

Actually Sherwood built separates as well, posted on December 3, 2014 at 03:42:01
DFaulds
Audiophile

Posts: 616
Location: Northeast Ohio
Joined: October 19, 2000
I have a pair of the SA3600 (I think that's the model#) power amps which use 4x6bq5's and I know they built a preamp as well because I missed buying one about 15 years ago. It looked pretty much like one of their integrateds.

The power amps are very nice, although like many of the pieces I've got in the stash, I haven't fired them up in a number of years. They show up on eBay maybe once every year or two, so I guess you could say they are not common pieces.

 

RE: Actually Sherwood built separates as well, posted on December 3, 2014 at 05:38:13
FlaCharlie
Audiophile

Posts: 940
Location: Gville, FL
Joined: June 1, 2003
Those amps (I think they're called the SA-360?) are quite rare. It seems they were only sold during the changeover from mono to stereo. Sherwood sold a model (S-4400, I believe. I've got one somewhere.) which had a mono amp section with a stereo preamp. This allowed the buyer - who, perhaps, couldn't afford stereo or was unsure if it would take hold in the marketplace, to upgrade to stereo later by purchasing the S-360 power amp. I don't think Sherwood ever intended for the S-360 to be sold in pairs since, to the best of my knowledge, they never made a stand-alone stereo tube preamp. After stereo was better established, they only offered stereo integrateds and receivers.

. . . Charlie

 

RE: Actually Sherwood built separates as well, posted on December 3, 2014 at 05:46:48
dls123
Dealer

Posts: 1214
Location: Beautiful B.C.
Joined: April 15, 2003
I rebuilt a pair of those for a customer a couple of years ago. They were the S360 amps. They were very good. Tube rectified and then a PPP quad of 7189/EL84 tubes. Used a 7199 as the AF amp and phase inverter. Sounded quite good. I remember adding a pot to dial the bias supply up and down a bit to match a particular quad of tubes....

As to the original question, I would keep the S5000

cheers,
Don

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 3, 2014 at 08:25:01
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Hi Mike,

I take it you are a fan of the Mullard drive stage. I have never heard it but I like how it looks on paper. With the standard 5/20 style EF86 driving a EC83/ 12AX7 cathode-coupled phase splitter, do you think the is enough juice to drive a pair of 6550/ KT-88's in PP, class AB ultra-linear mode?

TIA,

Dave

 

Well a guy here in Akron had the stereo preamp, posted on December 3, 2014 at 08:46:53
DFaulds
Audiophile

Posts: 616
Location: Northeast Ohio
Joined: October 19, 2000
He offered it to me for, I think $300, but that was back in the mid 90's and I thought that was way too much. Of course it's been a while so I guess it's possible that it was a preamp with a mono amp on the same chassis. Anyway, since I didn't get the amps until a few years later there was no pressing need for the preamp, although it looked pretty cool with the faux leather faceplate.

And yes S-360 is correct because it's on the Radiomuseum website. I couldn't recall the exact model number. There are also a few threads about the amp here if you search this forum.

 

Sherwood - no contest, posted on December 3, 2014 at 09:42:31
airtime
Audiophile

Posts: 11287
Location: Arizona
Joined: February 4, 2003
After decades of fiddling with stereos my keeper is the Sherwood S-5000. But have Mike rebuild it. That thing is perfect with the upgraded parts and caps. I no longer have ANY desire to upgrade or try new gear. Really can't see improving on the Sherwood.

Now I fiddle with my second string stuff for fun, not for serious listening.

Go for the Sherwood rebuilt.
charles

 

RE: Actually Sherwood built separates as well, posted on December 3, 2014 at 09:50:34
Sherwood Forest
Audiophile

Posts: 240
Joined: October 7, 2014
Yes, this is correct. The S-4400 was basically an S-5000 with only one output transformer, which was beefier, and wired for PPP operation. The preamp was the same. The S-360 was the upgrade to complete the rig and make it stereo. IIRC, the S-5000 was $189 without case, and the S-4400 was $159. The S-360 was $59 I think.... So, you can see their strategy. And yes, the S-360 is as rare as rocking horse shit, but not as rare as the S-1060, which I've never seen. I just managed to finally get my hands on an S-360 after years of looking for one in good shape and with the original cover. I paid more for it than I've ever paid for any Sherwood amp.

I would LOVE to see an S-1060, 6x7189 output in PPP operation for 60 watts. Must be friggin' awseome.

 

RE: Actually Sherwood built separates as well, posted on December 3, 2014 at 10:30:38






You got me curious so I pulled a couple of pics off the web.

The S-1060 looks as if there are only two tubes in the preamp section, two drivers/phase inverters, and six 7189 output tubes for a total of 10 (no tube rectifier? ). The S-5000 with big iron and 7189 outputs has five preamp tubes, two drivers/phase inverters, four 7189 outputs, and a GZ34 rectifier for a total of 12 tubes.

Judging purely from a parts selection perspective (having never heard a S-1060) I would bet the S-5000 betters it sonically within its power rating.

Doesn't matter, I'm keeping my Samra'd S-5000 F-O-R-E-V-E-R............
Or at least until I'm deaf or horizontal.







 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 3, 2014 at 11:09:42
Eli Duttman
Audiophile

Posts: 10455
Location: Monroe Township, NJ
Joined: March 31, 2000
"With the standard 5/20 style EF86 driving a EC83/ 12AX7 cathode-coupled phase splitter, do you think the is enough juice to drive a pair of 6550/ KT-88's in PP, class AB ultra-linear mode?"

The Mullard topology is very good. Mullard style circuitry is less dependent on O/P "iron" quality than Williamson style circuitry. OTOH, the small signal complement in 5-20 leaves (IMO) MUCH to be desired. Never forget Mullard published their designs in order to sell the tubes they manufactured. Both the EF86 and 12AX7 are low gm types. High gm is your "friend" in designs with long loop NFB, as it provides resistance against HF error correction signal induced slew limiting. IMO, the best vintage example of Mullard style topology is the Harman/Kardon Citation V. The Cit. 5 contains a 12BY7 as the voltage amplifier and a 6CG7 as the LTP splitter. Compare the gm of those 2 to the pair in the 5-20.

If you want PP UL mode KT88 "finals", Mullard style circuitry generally following the Cit, 5 example is fine. A 6922 in cascode would provide a high gm voltage amplifier in a current production tube. A current production ECC99 twin triode, with a mu of 22 and HIGH gm, is my choice for the LTP phase splitter. As cascodes exhibit poor PSRR, regulate 6922 B+ to put 180 V. on the upper triode's plate. Force symmetry in the differential gain block by using a 10M45S CCS in the tail, instead of a resistor. A modest negative rail under the CCS rates to be beneficial.


Eli D.

 

What Eli said., posted on December 3, 2014 at 12:17:18
Michael Samra
Dealer

Posts: 36118
Location: saginaw michigan
Joined: January 30, 2005
I like all types of topology depending on the amp..I like the Williamson in that is has very wide bandwidth and low distortion and I like the Mullard as well for certain circuits like the Sherwood and small UL amps.The EF86 and the 12AX7 can drive a pair of KT88s in UL but its not the best choice.The EL37 requires similar drive to a KT88 and the Knight KB85 does ok with it but you really should use a 6CG7 or ECC99 as ELi said because a 12AX7 can't fight it's way out of a paper bag.It's a fantastic voltage amp but the Citation 5 circuit is perfect. I like a pentode in the initial stage but the 6922 in cascade is perfect and they are currently manufactured.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken

 

You are correct and also have a pair of S360s, posted on December 3, 2014 at 12:20:16
Michael Samra
Dealer

Posts: 36118
Location: saginaw michigan
Joined: January 30, 2005
I thought I mentioned it but I didn't... What I wanted to say was thar Sherwood built mostly integrated amps and receivers and they were the best at it.That's what late night posting does to me.The didn't build a stand alone preamp.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken

 

RE: Actually Sherwood built separates as well, posted on December 3, 2014 at 12:21:31
Michael Samra
Dealer

Posts: 36118
Location: saginaw michigan
Joined: January 30, 2005
I changed the 12AX7 driver to a 12AT7 per Jim Mcshane and it worked nicely.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 3, 2014 at 13:17:06
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Hi Eli,

Thank you! I had to look up transconductance to get what you are talking about. I am also glad you translated the Citation circuit to readily available tubes, which is very important for me. It there a schematic available for such an amp? I don't think my current skills are up to designing an amp from scratch.

What attracted me to the Mullard is that not only do they give you a schematic, but they tell you how to build it from the ground up, including the chassis, wiring and layout (see link). It is almost "monkey see, monkey do" easy. I was planning to do an EL-34 amp first, and then use a Dynaco style output circuitry for the KT-88's (iron from Uncle Ned). I would use a similar sized Hammond aluminum box.

Dave

 

RE: What Eli said., posted on December 3, 2014 at 13:21:10
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Thanks! Is there a schematic for such an amp or maybe and EF86/6992 driver stage?

Dave

 

Eli, that's Greek to me?, posted on December 3, 2014 at 14:55:30
airtime
Audiophile

Posts: 11287
Location: Arizona
Joined: February 4, 2003
I just want to turn the pretty knob and listen!

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 3, 2014 at 17:21:50
Eli Duttman
Audiophile

Posts: 10455
Location: Monroe Township, NJ
Joined: March 31, 2000






Well, let's start with the Cit. 5. Then we'll look at changes.


Eli D.

 

The only one I know of is the Allen 75 that has a UL circuit., posted on December 3, 2014 at 22:01:39
Michael Samra
Dealer

Posts: 36118
Location: saginaw michigan
Joined: January 30, 2005
Its an EF86 into a pair of 6SN7s..It also has a 12AY7 but don't use that as its a preamp section for the organ..The circuit Eli suggested is perfect because even tho it's a triode in the initial stage,the way it is used it doesn't really have to fight miller capacitance.
"For every complex problem there is an answer that is clear, simple, and wrong" H. L. Mencken

 

RE: The only one I know of is the Allen 75 that has a UL circuit., posted on December 4, 2014 at 07:46:14
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Hi Mike,

Thanks for the suggestion! My fist tub amp was a Craftsman KT66 Williamson, so I like 6SN7's. I also have a lot of NOS & used 6SN7's because an amateur TV repairman neighbor gave me his stash of tubes. I will look at Eli's suggestion. I trust both of your judgments.

Dave

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 4, 2014 at 08:51:25
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Hi Eli,

Now that looks very interesting. I am pretty sure I have some 12BY7A's in my TV tube collection. They also seem to be going for a reasonable price. The 6CG7 is available new and is (if I recall correctly) is a 9 pin version of a 6SN7, which is a tube I like and have a few of. I feel pretty foolish, never having taken a close look at the Citation V circuitry, give all the praise it has received. I assumed I never would have found one for a reasonable price. Has anyone successfully made a DIY copy?

Dave

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 4, 2014 at 09:31:23
Jim McShane
Dealer

Posts: 5910
Location: Chicago
Joined: January 13, 2003
Dave,

Rebuildable Cit V cores do come up for sale from time to time, and that would be a great start for a killer amp.

12BY7As are not as plentiful as they used to be, so if it was me I'd wire the 12BY7A sockets to use the 6CL6 or 6197 and stock up on them. They're cheap and common right now.

Yes, the 6CG7/6FQ7 is a "9 pin 6SN7". The EH 6CG7s work quite well BTW.

As well, the stock power supply can be dramatically improved, especially as relates to improved screen regulation. There's also a few minor alterations to the audio path that you can apply and when you are finished you'll have an AMAZING amp - and an amp that can image like nothing I've ever heard.

If you need an integrated you can easily use a passive unit ahead of a Cit V. The V has an input impedance of about 1 meg and it only takes 1.2 volts RMS to drive it to full output. Most any line-level source can drive that load - just keep the IC cables from the passive to the amp as short as possible and use low capacitance cable. A 50K volume pot is a good choice.

You could clone a Cit V - but just like with the Cit II the transformers are a problem to reproduce.

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 4, 2014 at 14:10:42
Eli Duttman
Audiophile

Posts: 10455
Location: Monroe Township, NJ
Joined: March 31, 2000
I will attempt to augment Jim's excellent remarks.

A great thing about Mullard style circuitry is the fact that so/so O/P "iron" yields a decent result. Never forget that the better the "iron", the better the amp. Having issued the warning, I can say it is possible to "clone" the Cit. 5 using Edcor's model CXPP100-MS-6.6K O/P transformer. Will the result be as good as the superb H/K original? Almost certainly not, but the result will be GOOD.


Eli D.

 

It's a Funny Thing, posted on December 4, 2014 at 16:52:17
briggs
Audiophile

Posts: 1674
Location: Connecticut
Joined: April 16, 2002
I was in the business at the time they made these tube units. We stocked and sold Sherwood, Pilot, Scott, Fisher, H-K, Dyna, Eico and McIntosh electronics. We had KLH Nines on demo, and Bozak Symphonies.

I recall liking Sherwood but not favoring it over -- say -- Pilot. Perhaps it had something to do with the cartridges and speakers of the era. Perhaps Sherwood was better than we knew. It is also possible that Sherwood benefits more from modern component upgrading.

Anyway, it was not obvious to us that there was anything inherently superior about Sherwood, and if anyone had suggested, as someone here did, that a Sherwood amp was comparable to a Mac MC225, well...




 

RE: It's a Funny Thing, posted on December 4, 2014 at 20:30:58
DaveV
Audiophile

Posts: 513
Location: SC
Joined: December 26, 2009
Hi Briggs.
My comment about selling "one" of my MC225's doesn't mean that I don't like them or that I think the S5000 has a better amp section.
I recently got a good deal on the Sherwood and found that it, combined with a much smaller pair of speakers I already had, pleases me enough to live with the combo.
It's the "compromise" I've been looking for and it's one heck of a bang for the buck because everytime the stylus hits the grooves it makes me happy and that makes it easier for me to sell some things off and put the money into things that would better serve me at this point in my life.
But I get what you mean about a funny thing.
When I see the current interest and going prices for some things I would never have considered when they were new, it amazes me.

 

RE: It's a Funny Thing, posted on December 5, 2014 at 11:47:42
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
That is not as surprising to me as the almost universal acceptance of the early, horrible sounding solid state equipment.

Actually, I am not that surprised at what you say. When I sold audio equipment in the 80's, we sold Yamaha separates. However, I did not pay much attention to them. I had a Conrad Johnson preamp and a VSP amp in my system, and I was far more interested in the Tandberg, Revox, Adcom and Perreaux separates to pay much attention to the Yamahas. Then I picked up a Yamaha C4/M4 for dirt cheap and my eyes were opened up. These things really sounded great. I current use a Yamaha C-2x preamp and I like it so much, I really am not interested in looking at other preamps. However, in the 80's, I would not have considered Yamaha,

Think back, I'm guessing the Sherwood equipment was never tried on the KLH 9's or the Bozak Symphonies.

Dave

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 5, 2014 at 11:56:20
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
Thanks for the great advise Jim, including the rewiring. If I can get my hands on a Citation V That sounds like the way to go. It sounds like it would be just the thing to drive my Spendor BC-1's.

Dave

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 5, 2014 at 12:01:21
Crazy Dave
Audiophile

Posts: 14371
Location: East Coast
Joined: October 4, 2001
I will add the Edcor to the list. I wasn't really aware of them until you mentioned their single ended transformers in another post. I was wondering if they made good PP transformers too. AT $98, the price it right.

Dave

 

RE: It's a Funny Thing, posted on December 6, 2014 at 05:48:12
briggs
Audiophile

Posts: 1674
Location: Connecticut
Joined: April 16, 2002
Obviously the Sherwood -- or any other integrated amp of the period -- would have been a mismatch to KLH Nines or Bozak Symphonies. We drove those speaker systems with an MC240.

 

RE: It's a Funny Thing, posted on December 6, 2014 at 10:02:41
Brian Levy
Audiophile

Posts: 2438
Location: Toronto
Joined: June 5, 2000
You should have tried the MA230. Easily drove the Nines and has enough juice for the Symphonys, though I never had a chance to try it on the Bozaks. The MA230 was a nice sounding mate to the Nines provided you kept them below clipping. The maximum voltage the Nines can handle is 49.5 and the MA230 hovered right there.

I have driven my Symphonys with the S5000II. No problem unless you like to rattle windows.
Don Brian Levy, J.D.
Toronto ON Canada

 

RE: Actually Sherwood built separates as well, posted on December 6, 2014 at 10:10:06
Brian Levy
Audiophile

Posts: 2438
Location: Toronto
Joined: June 5, 2000
Sounds like they started with a mono version of the S5500 preamp.
Don Brian Levy, J.D.
Toronto ON Canada

 

RE: Well a guy here in Akron had the stereo preamp, posted on December 6, 2014 at 10:12:52
Brian Levy
Audiophile

Posts: 2438
Location: Toronto
Joined: June 5, 2000
With that faceplate it would likely be from their earliest days and mono.
Don Brian Levy, J.D.
Toronto ON Canada

 

RE: It's a Funny Thing, posted on December 7, 2014 at 05:56:24
briggs
Audiophile

Posts: 1674
Location: Connecticut
Joined: April 16, 2002
Bozak Symphonies are sensitive enough to be driven by a Sherwood in a modest-sized room, and probably sound good. If you were spending $1000 (in the early 1960s) on a pair of speakers, however, you would not be likely to settle on a $200 (or so -- I don't recall the exact price) integrated amplifier.

The Nines, however, were another matter. With low sensitivity, and limited dynamic range and power handling, they presented a very different model. The MC240 we used was adequate and did not audibly clip, but you could hear a substantial difference when you substituted an MC275.

 

RE: Which tube integrated to keep forever? Pilot or Sherwood?, posted on December 15, 2014 at 21:12:25
lektrik
Audiophile

Posts: 447
Joined: May 31, 2002
That's a tough one because I've had both, recapped both, and like both very much. I'd have to give the edge to the Pilot 245 because it just did everything well as the S-5000 did, but a bit sweeter.

I must admit that I went the extra mile and replaced all the ceramic caps in the tone controls with polystyrene/foil and copper leaded silver mica caps on the 245 and that put it over the edge in the sweetness category.

That's a tough decision since they're both very, very good integrateds.

Larry D.

 

Page processed in 0.035 seconds.