Hi guys,

Picked up an "AS IS" sherwood receiver at the swap meet today for $80, appeared to be in good shape with one burnt out Electron 7868 tube. All channels are working I will have to replace the one tube. My first intro into tubes, well I had a tube console but it was such an inconvenience that I rarely used it. Anyways The sherwood has a beautiful face to it. How did I do? Good score or so so. Oh yeah will post pics soon.

It may very well be a good score. But bear in mind that if you have a 7868 that seems "burnt out" then there is likely a mate to it that is not much better. They generally get replaced as sets--mostly pairs or quads.

I don't have a sherwood but a Scott 340B and Fisher 400 (7868 also) The sherwoods have an excellent reputation for sound quality. I've read only good things about them do a search on them, also the info on this site regarding Fisher and Scott receivers will be also be usefull.

The Sherwood S-8000 is a great performer IMO; very good tuner section. I think you have the potential for a very good score there when brought up to spec.

It will need refreshing, but it is well worth refreshing.

Really great grab. I think the S8000 is the best of the tube receivers. You got a S3000 tuner and S5500 integrated on one chassis.

Make sure to replace the grid coupling capacitors on the output tubes. They short and kill tubes. Its usually why you find them with dead outputs.

Replace them before you retube or you're wasting your money.

Make sure to replace the grid coupling capacitors on the output tubes. They short and kill tubes. Its usually why you find them with dea[d] outputs.

Replace them before you retube or you're wasting your money.


Ayep! :thmbsp:

Both channels are working now with NO distortion guys, one of the electron 7868 tube looks to be burnt and is not lighting up like the other 3 so I'm assuming it should be replaced. Will tubes continue to work for a short period after they've burned out?? FM is working also as are CD hooked up to it. Sounds great if a bit boomy but maybe my choice of speakers. I've currently got them hooked up to a KLH model 6 and it's pretty nice, wasn't a good match for the epicure M110.

1) No they won't.
2) Unless you know that it has been done in the modern era... Change, at the very least, the coupling caps before you listen to it any more, or risk damaging the output tubes and the output transformers.

....
2) Unless you know that it has been done in the modern era... Change, at the very least, the coupling caps before you listen to it any more, or risk damaging the output tubes and the output transformers.


Ditto...

While i can't tell you if you have a problem with bad caps i can tell you this.You want to replace that set of worn power tubes with a set of eh 7868's.I replaced my set on a sherwood s 7700 and got literaly double the power.No joke no exaggeration.It still sounds good too.
If you do have a problem it should be cheap to fix by a tech.It is well worth the effort.The Sherwood's a step ahead of the other tube receiver.I have not heard them all but it does beat my fisher 500 c pretty handily.
If you do install new output tubes.Those 7868's need to have their pins re tensioned.So the new tubes will fit.Just make sure you unplug it overnight before you do it.

Thanks for all the suggestions and input gu ys. So I will want to replace all four at once or perhaps the one that is paired up with the bad one on the same channel. I'm looking at ebay and do see them come up, do the 7868 tubes also go under different model numbers or will all 7868 have that number designation? It doesn't appear to be too common as I haven't seen many on ebay. I checked out antique electronics but their price is high.

electro harmonix makes the new 7868. YOu can get matched pairs for around 50 dollars each. Just do some research and shop around. Google is your friend there.

Just replace all four coupling caps. Coming from personal experience, I believe the doing the minimalist approach on tube gear is a foolish thing to do and a big risk if you plan to use it at all. At the age of the components, failures are more likely to happen than not and some failures can be damaging to other parts of the machine as well. If it's going to get used I will usually replace the coupling caps. I will put the power supply caps on an ESR tester and leakage tester to determine if they are usable.

Just remember: in general, pretty much everything in vintage tube amps is easily replaceable except the power transformer and the output transformers. Whatever you do or don't replace/restore when you refresh a piece of equipment like the Sherwood in question, consider the likelihood of a decision not to replace a component on the potential loss of one of the transformers.

This is the risk-based approach. Professionally, I am all about risk-based assessment. It's all the rage these days...

Hi I'm at the exact polar opposite opinion from many on here.I have read a lot on old guitar tube amps.Those techs are loath to pull old component's from units unless their not working right.Why ?It changes the sound.They were voiced a certain way.Its part on that magic only a old tube amp can give you.Yes some parts may be out of spec but that's why it sounds so good.These guys are right if the wrong part lets go you might lose a transformer.But you might put in 716 orange drops and lose that sherwood magic too.
I personally rebuilt a hk a 224.New caps and resistors.Before it was grainy.Warm and grany.I thought new parts would fix that.It did not.It made it boring.It sits in a closet now unused.
Try the new tube route first.It cost me 400 to get nos tubes on top plus eh's on the back.The improvement was great.Try the eh's their worth it.then if you like it look for a tech.
Oh always be close by your tube amp babysit it.Even if everything is replaced don't trust it.

Hi,
I have been upgrading my Sherwood S8000 for the past few months. IMO: Replace the coupling caps with Poly caps, Replace the power tubes with 4 EH tubes. Both of these changes made a big (positive) impact on the sound. The Cathode electrolytic is a must to replace. I would like to replace my power supply caps but am having a hard time finding appropriate replacements that will fit under the hood (although I run mine without the cover and up on blocks). I love mine so much I am looking for another one to work on for my living room.
Good luck and enjoy this fantastic tube receiver!

sweet receiver !

I still have a little work to do on mine (havent touched it in months) but it's a keeper for sure :thmbsp:

definitely do a recap sooooooooon . . . your tubes (and transformers) will thank :yes:

terryfox - one thing to consider is how these units sounded when they were *new* . . . If a component (i.e leaky cap / drifted resistor) is out of spec from what the original engineers intended, it doesn't sound as it should.

I've always thought of it in car terms . . . do I want to drive a 1960 Corvette with all original suspension bushings, shocks, and sparkplugs ? NOT A CHANCE . . . the car needs an overhaul .. .

whether its a frame-off rotisserie restoration, or a more modest engine & suspension rebuild, any classic worth playing with is worth restoring :yes:

at the very least recap that baby and throw some fresh output tubes in it (preferably vintage :yes:)

almost forgot - here's some shots of mine for inspiration :D

the undercarriage shot shows all original components . . . I've recapped (actually mhardy did :D) one output channel (maroon caps) , and have yet to get around to doing the other channel . . .arguably, I should go through the whole damn thing, check voltages, and recap the power supply, but I'm having too much fun with console amps right now :thmbsp:



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Hi i have a earlier s 7700 its similar but very different from you guys later s 8000's.What electrolitic 's have you seen that will fit with the same voltages.I have never seen a multi unit cap the same voltage as the power supply on my s-7700.The s 8000 looks to have the same electolitics.
markus why did you not replace the large brown caps?What are you other caps i have never seen a light blue/green cap before.
If i were to do mine i would use auricaps.Im sure someone who has just spent 80 bucks on a receiver is not going to want to pour the money its going to take to bring it up to snuff.New tubs ,caps coupling and power and paying for installation. a sherwood needs a pro.The sherwood as good as it is is not worth that money.At that price level you can buy one of those chinees tube amps.Most are well made look modern and perform well.

Hi i have a earlier s 7700 its similar but very different from you guys later s 8000's.What electrolitic 's have you seen that will fit with the same voltages.I have never seen a multi unit cap the same voltage as the power supply on my s-7700.The s 8000 looks to have the same electolitics.
markus why did you not replace the large brown caps?What are you other caps i have never seen a light blue/green cap before.
If i were to do mine i would use auricaps.Im sure someone who has just spent 80 bucks on a receiver is not going to want to pour the money its going to take to bring it up to snuff.

I guess those caps might look brown . . . they look maroon in real life :D

before I got comfortable recapping, mhardy recapped one channel with orange drops, but I have yet to do the other channel, as I didn't have the 600 volt rated caps . . . even so, I pull it out every so often and enjoy it :yes: I can't tell one channel is stock - these Sherwoods sound really sweet.

And you are totally right - to get one of these up to snuff (100%) requires LOTSA work .. . hell . .. phono, preamp, output stage, power supply . . . thatsa lotta caps and resistors to check / replace . . . For extended use, mine will require the other (output) channel to be recapped. there is no audible hum, so I'll leave that stock. I also looked around for suitable 'drop-in' multi-value caps for the PS, and struck out. That being the case, I'd really like to use it on a dedicated variac so I could run it (and other relatively fragile) vintage amps - my house has 125V coming out of the wall ! :yikes: I know these old tube amps were designed with 10- 20 % component variance, but hitting them with modern wall voltage just seems mean!

I run plenty of magnavox and other vintage console amps straight off the wall, but without a full recap, I feel these rarer birds (Sherwood, Scott, Fisher, etc) deserve more of the kid glove treatment . . .

Terryfox, the value of a restored Sherwood 8000 is very speculative as so few have been put on the block, unlike say the Fisher 500-C, etc. $80 was a steal as I've seen units needing work hitting the $300+ range provided they are physically in good shape. Average auction prices are not good indicators of the values. I personally expect to put in about $200 is a vintage unit on average to make sure it is reliable (not he same as a restro) so assuming the average price of say $325 for a cosmetic keeper plus $200 in repairs including plus an alignment of the tuner in the range of $125, it would not be unreasonable for me to have a sunk cost of say $650 into one. Marcus' unit is cosmetically not in good shape as it has the typical front panel white paint wear, so I's take of about $200. The $200 is about the cost of a roached parts unit with a good faceplate.

The above does not include the cost of tubes as they can be vary variable depending on tastes and I apply the same estimate of repairs cost to a unit whether tube or SS for valuation purposes.

Vintage is not about cheap. There are plenty of cheap units out there new. It is about retaining, restoring and appreciating what was. Like the classic car hobby, it is not a bargain hobby but a hobby of love and appreciation for fine engineering and production. There are those who hang around it for profit and those who start in it as a cost savings way of getting a good rig but as you progress further and further into it it is not going to be a cheap hobby. Just look at some of the collections the hard core lovers are accumulating. As for investing in a Chinese (or any other country's amp), it is not an alternative for a hobbyist though it is not to say there may not be one or more of the newer units hanging around also. However, it is not to say it can replace a vintage unit. I have 2 Eton S350DL (Chinese built) am-fm-sw radios that has a lot of nice features and a vintage Hallicrafters tube unit that gets am & sw. I like the Eton and listen to one in the office but at home the Hallicrafters easily gets used far more. For every hour on the Hallcrafters, maybe 15 minutes on the Eton. The Eton is more sensitive, a better dx'er on am, has fm (even in stereo on the phones or thru the line outputs) and is on par with the Hallicrafters thru about 10mhz though after to 30mhz, the Hallicrafters is better. But putting on those old magnetic headphones or listening to the sound through the old 4" tinny speaker just seems less sterile. The thrill factor is just better.

Value also depends on if a person does much of the work themselves. My second Fisher 400 cost me 100 in good working condition, I don't think I spent more than 30 on new parts, not including output tubes. After cleaning the unit up it looks almost new. I then spent around a hundred for an alignment and a tech to check it over. It provides beautiful sound. As for output tubes, new gear will at some point also require new tubes. Total cost was well around 300 for a restored/upgraded tube receiver. I did the same for a very nice Scott 340B I snagged years ago for 15 at a yard sale. Granted I was lucky in getting good units at a low or a very fair price and I enjoy doing the work myself which adds to the fun. Much like a vintage car (I also have one of those) working on them yourself is part of the enjoyment and a must to save money. Vintage audio is much cheaper than owning vintage cars no matter who does the work. I also very much like the look and sound of vintage gear.

Marcus' unit is cosmetically not in good shape as it has the typical front panel white paint wear, so I's take of about $200. The $200 is about the cost of a roached parts unit with a good faceplate.



yup . . . in a perfect world, I'll stumble across a parts unit with fried transformers, and aminty faceplate (everyone can dream :D)

I consider my Sherwood (and my growing collection of Scott) a labor of love . . . I'm in for the long haul . . . it could be YEARS till I truly restore (electrically anyway) any of them, especially since I'm a DIY'er. I'm cutting my teeth on console amps for now :yes:

Yeah, some of us need a retirement strategy...

Guys, I'm going to start with the one burnt out output tubes and coupling capacity for the changeout. Do the tubes have to be of the same brand?? I currently have all Electron 7868 in there, 3 appear to be good. Can I get another 7868 brand like someone suggested an EH or RCA brand and replace or will I need to get a whole new set of 4 tubes or at the very least have the same tubes on the same channels? Great info from you guys that know the unit. Now I'm thinking I got an excellent deal on this the face place looks great!

Guys, I'm going to start with the one burnt out output tubes and coupling capacity for the changeout. Do the tubes have to be of the same brand?? I currently have all Electron 7868 in there, 3 appear to be good. Can I get another 7868 brand like someone suggested an EH or RCA brand and replace or will I need to get a whole new set of 4 tubes or at the very least have the same tubes on the same channels? Great info from you guys that know the unit. Now I'm thinking I got an excellent deal on this the face place looks great!

well. .. ya do whatcha gotta do :D

I didn't have $100 + to blow on fresh output tubes, so I ended up trading a TON of old NOS TV parts (transformers, tubes, etc) for four strong (but mismatched) 7868's . . .

I say recap, throw a spare 7868 tube in there, and see how she sounds (after warming up slow on a variac of course) :thmbsp:

You can limp along with 4 mismatched tubes.I had 4 mismatched for awhile it sounded good but never made full power.I replaced them with a matched quad of eh 7868's.It was worth every penny.If you want a cheap quad check ebay.Thats for worn tubes or new eh's.These amps were designed to work best with a matched set.

Forgive my ignorance but what is a VARIAC??

Forgive my ignorance but what is a VARIAC??

basically a variable AC supply .. .plug it into the wall, plug your sherwood into it, start at 0 volts, and slowly (time depends who you talk to) bring the voltage supplied to the sherwood until you're at 'wall voltage' (110-125V)

what this does is hit the power supply caps with voltage slowly, so there's a better chance of maintaining their integrity. you'll know if the Power supply is FUBAR if there's a hum, or if it simply doesnt pass sound.

read the stickys. and do a search for variac here on AK, and you'll get an idea of what you need :thmbsp:

Forgot to mention . . .
The EH tubes have a larger diameter pin size than the orignial so they will need to be "forced" in. I decided to replace my orignal tubes although they sounded great and now that I have them in the unit, my original ones I am sure would be too loose in the sockets. Just wish I had another Sherwood to put these extra tubes in so that I could have another one to restore. Guess I have caught the tube bug!

As for the units from another country, I have not tried any of there tube equipment but do use a DAC that I have modified. It sounds much better than the DAC in my Marantz CD player.

Enjoy your unit!