View Full Version : US made "Shell" high fidelity amplifier - Info?


pqrannes
03-29-2008, 10:44 AM
I've just found a "Dual 10 watts" American made tube amp by the "Shell Electronics" (Westbury NY). On the front plate it says "Northport" and underneath it says "Model 210P".

It looks like a single-end amp with two 7189 (el84?) as output tubes. Its equipped with ecc82s and ecc83s and an (broken) EZ81 in the power supply section.

The overall condition is not good, it's very dirty and rusty and even the brassy front plate is covered with rust.

But I like it! It's my first US made tube amp (Ive got a Dyna tuner sitting around waiting for alignment)

I haven't been able to find any info online on either the Shell Electronics or the amp it self.

Maybe some of you AKs got some info? Anything!

I'll ad some pictures later to night: got to feed the family first!

Peter, Denmark

jaymanaa
03-29-2008, 10:55 AM
I have never heard of Shell electronics either, but I look forward to seeing the pictures.

pqrannes
03-29-2008, 12:04 PM
Well, the dish (Osso buko) is in the oven and here are the picture:


http://rannes.dk/pqr/billeder/shell-1.jpg
The rusty front plate.

http://rannes.dk/pqr/billeder/shell-2.jpg
And from above

http://rannes.dk/pqr/billeder/shell-3.jpg
The label from beneath.

Peter Q.

ldatlof
03-29-2008, 12:44 PM
Eico was located in Plainview, NY not very far from Westbury, NY - just a thought.

pqrannes
03-29-2008, 03:05 PM
I just pulled two so called "bugle boy" (amperex) ecc83 from this rusty amp. It can't be that bad then?

Peter Q.

fredmarantz
03-29-2008, 05:32 PM
Yup - I saw that one at the market- and passed on it. Too much work for me to have it up and running in restored condition - but it sure is a nice thing. Didn't see the 7189's - yes they are a EL84-version - a very good one.

Regards
Freddy

diamondsouled
03-30-2008, 12:51 AM
Different Shell model up on eBay. Looks a bit like an HMV.

http://cgi.ebay.com/Shell-Meadowbrook-3030P-7591-Stereo-Tube-Amp-Works-RARE_W0QQitemZ140220017111QQihZ004QQcategoryZ73369 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

pqrannes
03-30-2008, 01:02 AM
Yup - I saw that one at the market- and passed on it. Too much work for me to have it up and running in restored condition - but it sure is a nice thing. Didn't see the 7189's - yes they are a EL84-version - a very good one.

Regards
Freddy

Hi Fredmarantz,

I guess this big world is very small. We could have knocked our heads together at the market yesterday in our hunt for tubestuff!:banana:

Peter (Denmark)

pqrannes
03-30-2008, 01:16 AM
Different Shell model up on eBay. Looks a bit like an HMV.

http://cgi.ebay.com/Shell-Meadowbrook-3030P-7591-Stereo-Tube-Amp-Works-RARE_W0QQitemZ140220017111QQihZ004QQcategoryZ73369 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Thx diamondsouled!

We even have the address of the company "112 state street, Westbury" now and could have someone to go there and see if the company is still around:tresbon:!

The amp sure is a sibling to mine! And a nice looking one too - w. good iron it seems. Mine will never look that good, but maybe it will play some day!

Peter

fsjonsey
03-30-2008, 09:31 AM
Probably the best thing you could do is strip it down to the bare chassis, sand and paint everything, and then do an electronic rebuild. If the lettering on the face plate is recessed, then you may be able to get away with light sanding and polishing, and applying a coat of clear lacquer.

pqrannes
03-30-2008, 03:02 PM
Probably the best thing you could do is strip it down to the bare chassis, sand and paint everything, and then do an electronic rebuild. If the lettering on the face plate is recessed, then you may be able to get away with light sanding and polishing, and applying a coat of clear lacquer.

Thx for the suggestions!

I guess it must the hard way if it's going to look good. The case could be sanded down and re-dyed and oiled.

The hard part is the rusty front plate; I can't see how to get of the rust without damaging the lettering on it.

The electronics doesn't look bad. I only see three caps and the power section cap to recap if necessary.

Peter

gearhound
03-30-2008, 03:11 PM
It was from an old 50s promotion................

Buy 12 gallons of gas at any Shell Service Station (10 gallons in Texas 'cause they only have 10 fingers)....and receive a FREE tube amp.

Steve

fsjonsey
03-30-2008, 04:40 PM
Thx for the suggestions!

I guess it must the hard way if it's going to look good. The case could be sanded down and re-dyed and oiled.

The hard part is the rusty front plate; I can't see how to get of the rust without damaging the lettering on it.

The electronics doesn't look bad. I only see three caps and the power section cap to recap if necessary.

Peter
An option for the front plate would be making a hi-resolution scan of it in a flatbed scanner, and using photoshop or the gimp ( a free alternative) to make new water slide decals.

http://www.mcgpaper.com/decalpro.html

pqrannes
03-30-2008, 04:54 PM
An option for the front plate would be making a hi-resolution scan of it in a flatbed scanner, and using photoshop or he gimp ( a free alternative) to make new water slide decals.

http://www.mcgpaper.com/decalpro.html

I've been thinking about something like that as the final solution.

It is strange with that faceplate. The backside is not corroded at all and can be polished with Brasso the usual way (the cloth becomes black).

But the front is more stubborn. Brasso doesn't really bite. I wonder if it is covered by some kind of clear coating. And it is thus the coating that has the 'rust'.

I've found out that the plate is drawn by a magnet so it is not pure brass.

Peter

soundmotor
03-31-2008, 07:13 AM
The output and power transformers are pretty big considering. My EICO AF-4 is smaller on both counts. In general with gear of this vintage, larger is better. I might be tempted to pull the iron and build it into a basic stereo amp rather than restore it.

pqrannes
04-01-2008, 03:56 AM
The output and power transformers are pretty big considering. My EICO AF-4 is smaller on both counts. In general with gear of this vintage, larger is better. I might be tempted to pull the iron and build it into a basic stereo amp rather than restore it.

It turned out that the front plate is iron of some kind. Brassy iron, I guess, and the corrosion is ... rust. I'm going to polish as good a possible and leave it there; 'in original condition' must be the description. I'll clean the chassis, I'll get an EZ81 and fire it slowly up.

If it plays I've got an American tube amp in working order!

PQR

Toasted Almond
04-01-2008, 06:00 AM
About ten years ago I found two "Shell" pieces. They both worked perfectly. A small tube integrated and a FM tuner. One was called the "Hampton" and the other the "Manhasset".

pqrannes
04-01-2008, 06:18 AM
About ten years ago I found two "Shell" pieces. They both worked perfectly. A small tube integrated and a FM tuner. One was called the "Hampton" and the other the "Manhasset".

Thx,

It seems like they sticked to locations in naming their stuff!

PQR

Toasted Almond
04-01-2008, 06:38 AM
Obviously they enjoyed Long Island.

I foolishly traded away both pieces for some speakers I coveted.

pqrannes
04-01-2008, 03:07 PM
Obviously they enjoyed Long Island.

I foolishly traded away both pieces for some speakers I coveted.

My geography knowledge of New York State isn't good enough; was the company itself situated at Long Island?

PQR

pqrannes
04-06-2008, 03:12 PM
I've variac'ed life back in this little amp. It's playing but not sounding very good, yet!

When I first put the tubes back in and turned it slowly up it didn't play at all. A little hum and only one of the output 7189 tubes was glowing. Actually only three out of six tubes glowed and got hot.

Some shots of De-oxit in the the tube sockets (amp turned off) help and now 5 out of six are glowing and the amp is playing. I can't get the last 12ax7 to light up and have tried swapping the 2 12ax7s around, even tried with other 12ax7s. This little 12ax7 will not glow!

I guess that is why the amp doesn't sound good yet, there is lots of distortion, especially if I turn up the bass.

Edit: I forgot to mention that the two last tubes are 12au7s. How the amp is designed is not clear to me (I'm still not technical skilled!).


Peter Q

pqrannes
05-21-2008, 03:06 PM
I'm giving the little Shell amp another try and fired it up to night. I still doesn't sound good. Distortion from both channels.

What is most likely; the 7189 tubes are worn down or some other component has failed after some 40 years?

I wonder if I could give it a try with some (not important) el84 tubes -just for a short while to test the amp without the 7189s? Or maybe I should get a pair of Russian 7189 (el84Ls) like these on ebay (http://cgi.ebay.de/EL84M-Roehren-Tubes-7189-6P14PEV-EL84-E84L_W0QQitemZ130222061954QQihZ003QQcategoryZ65890 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem)?

PQR

Tom Bavis
05-21-2008, 09:09 PM
Leaky capacitors are likely, weak tubes are a possibility. Caps are cheap, and seem most likely - they'd affect EVERYTHING.

pqrannes
05-23-2008, 11:32 AM
Leaky capacitors are likely, weak tubes are a possibility. Caps are cheap, and seem most likely - they'd affect EVERYTHING.

Thx Tom,

Changing the capacitors most be the way to go.

Here is the layout of the below of the amp:

http://rannes.dk/pqr/billeder/shell-10.jpg

I find two not identical paper "Super-cap. dry electrolytic capacitors":


http://rannes.dk/pqr/billeder/shell-12.jpg

with the value of 10 mfd and 450 V DC
and:

http://rannes.dk/pqr/billeder/shell-13.jpg

with the value of 100 mfd and 50 V DC.

Knowing next to nothing about electronics the amp being a two channel amp I expected to find two of everything (almost). But it does not seem to be symmetrical constructed. I guess it is not a SE amp with two 7189 tubes but some kind of PP with a double use of each tube?

At the AV 100 V outlet I find a new (newer) Danish cap (0.5 mfd, 600 WV AC/400 WV DC) between the chassis and one of the legs of the poles of the outlet; similar cap - but apparently original - is at the other poles of the outlet.

http://rannes.dk/pqr/billeder/shell-14.jpg

Bonus info: i've been feeding the amp via a small variac and a 220V/110 V stepdown transformer. I've noticed that the amp sounds a little bit better (a little less distorted) when I kind of overfeed it (about 120-125 V I guess) with the variac. What does that show?

Peter Q

Tom Bavis
05-23-2008, 03:09 PM
The caps from line to chassis are called "Death caps" by the guitar guys... you don't want any leakage there! The 0.5 uF does NOT belong - it will pass about 25 mA at 120V/ 50 Hz and that could be deadly. The amp will work without either one - I remove them and change to a 3-wire cord. The disc caps are probably OK, the electrolytics are probably bad. The big silver can cap MIGHT still be OK, but if it heats up, it's bad for sure.

pqrannes
05-23-2008, 03:38 PM
The caps from line to chassis are called "Death caps" by the guitar guys... you don't want any leakage there! The 0.5 uF does NOT belong - it will pass about 25 mA at 120V/ 50 Hz and that could be deadly. The amp will work without either one - I remove them and change to a 3-wire cord. The disc caps are probably OK, the electrolytics are probably bad. The big silver can cap MIGHT still be OK, but if it heats up, it's bad for sure.

Thx again,

The original "Death cap" seems to be 0.033 mfd while the replaced are 0.05 mdf (not O.5 mdf as I wrongly wrote).

Guess I have to replace the two electrolytic caps? The big silver cap must be part of the power supply: since it's not hot, not leaking and the amp is not humming I guess it is OK.

Bye the 3-cord do you mean that I should make add a ground wire connected to the chassis instead of the two death caps?

Do you have any clues about the layout of the amp Singled ended or not?

Peter Q.

pqrannes
05-30-2008, 11:39 AM
HO,

I'm not alone. Or rather my little Shell is not alone in the world.

Another one is being sold at ebay here: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=130225604590

It even comes with a Heathkit FM-3A Tuner!

No new info in the add, but only the confusing mentioning of 2 x 7185 (?) tubes; I guess the seller have been misreading the tubes/board - they suppose to be 7189s

himm37
05-30-2008, 12:07 PM
My geography knowledge of New York State isn't good enough; was the company itself situated at Long Island?

PQR

Yep! FWIW, Harmon Kardon was 1st located in Plainview LI, not to far from Westbury.

To think, Growing up on LI, I was surrounded by all this great gear!

pqrannes
12-28-2008, 10:32 AM
I owe it to you to follow up on this story.

I did change the two yellow caps to new ones and it didn't change a bit. The little amp still sounded distorted and so.

Then recently I borrowed a good and calibrated tube tester (AVO 160) and among the many tubes I tested were the two 7189 from the Shell. The two tubes actually tested very bad (down to about 20-30% on the AVO).

From Berlin, Germany, I ordered at pair of Sovtek el84M which are substitutes for the 7189s. The tubes arrived before X-mas and along with other tested (and good testing) tubes the Shell was re-tubed.

Does it play? Yes, indeed! How does it sound?

I first tried it out (on the bench) with a pair of uneven vintage speakers in no-name (and open) boxes. It sounded very good and promising. I then (still on the bench) tried it out with a pair of full range Coral Beta 8 in a pair of Lowter Acoustica 116 back loaded horns: I must admit I found the sound a bit boring and unpersonal.

Then back from x-mas days at the summer cottage it set the Shell amp properly up with a pair of 60s German Isophon PH2132 full range speakers units in big open boxes (the rear side is removed) like this:

http://rannes.dk/pqr/billeder/ikea-ben%20010.jpg
(this is not my music room)

And this set-up sounds very, very good. I'm amazed!

The sound stage and image in the "hotspot" are better than I have ever heard it here before. Sitting in the right position the music forms a 3D circle round you head and you are 'in the middle' of the music ....... (this is goose bumps!)

Normally I play on a huge pair of three-way horn speakers (very much like Klipsch Belles) and a Braun CSV-13 el84 PP tube amp or a SS Sansui AU-9900 with eg. Dynaco A-25 (or JBL L-86s or something else). But I've never been near a sound stage and image like this with my many set-ups previously.

And it got me thinking. Is it the little SE tube amp or the (kind of) open baffle full range speakers that are doing the trick? Or maybe the combination?

Peter Q.

pqrannes
01-01-2009, 03:12 PM
Well, while you good people overcome the season (and Christmas) celebration (Happy New Year to everyone) and (especially) add at bit of info about the rare Long Island-based Shell Electronics, I got curious and made a little test.

I ran the open-baffle-ish speaker with my Braun CVS-13 el84 pp tube amp. And the conclusion? The magic in the above mentioned setup is the little SE-7189 tube amp! The Braun sounded OK with OB-ish Isophon but the magic was gone.

Thus: the magic comes from the unknown Shell Northport SE tube amp!

What I still need to find out is this: are SE tube amps known to have very goog imaging and sound stage? Or is this little amp just very good?

Next test to run is to try the amp out with my Klipsch Belle-ish three way speakers. But not to day, the first day of another year, one test a day is enough. Now I'll turn to music (an album by Mark Hollis of "Talk Talk").

Peter Q.

Nirky
01-01-2009, 03:37 PM
I don't know about SE & soundstage, but most of the tube amps I own are single-ended. Been experimenting with SE & push-pull amps for close to 5 years now. Harmonics, less feedback, more direct signal path, who knows, they just sound better to me. Glad you got yours working like you want, is it time to update your sig? :)

pqrannes
01-01-2009, 03:48 PM
... is it time to update your sig? :)

I guess it is. I've got a lot of stuff and changes happen all the time. Maybe I should keep the signature less specific?

Thx for you feed back!

PS I've just edited my sig!

Thespeakerdude8
01-01-2009, 04:55 PM
it looks an awful lot like Merril SA-10's or the oddball AMD SE el84 amps.

pqrannes
01-02-2009, 02:08 PM
it looks an awful lot like Merril SA-10's or the oddball AMD SE el84 amps.

Thx, I've looked in vain for pictures of these kind of amps on the web. Maybe someone can help?

PQR

pqrannes
07-30-2009, 02:16 PM
A friend just spotted two Shell tube amps in two ebay auctions.

Here they are:

http://cgi.ebay.com/Shell-Stereo-60s-vintage-tube-Stereo-Int egrated-Amp_W0QQitemZ250472664888QQcmdZViewItemQQptZVintag e_ Electronics_R2?hash=item3a51558f38&_trksid=p3286.c0.m14

http://cgi.ebay.com/TUBE-SINGLE-ENDED-STEREO-INTEGRATED-AMP- SHELL_W0QQitemZ360175364331QQcmdZViewItemQQptZVint age_Electr onics_R2?hash=item53dc1fe8eb&_trksid=p3286.c0.m14

And for future reference (when the auctions are all gone) here are some pictures.

The little SE (a near sibling to mine):

http://rannes.dk/pqr/billeder/se-4.jpg

and the other larger model 2020P:

http://rannes.dk/pqr/shellstereo-1.jpg

If only they weren't for sale on the wrong side of the Atlantic ...

PQR

similost
07-30-2009, 02:28 PM
Your post will probably be edited since links to auctions are not allowed outside D&S... cool little amps though...

KGBMAN
07-30-2009, 02:46 PM
What's that object between the "Treble" and "Bass" knobs?

Is that a power indicator lamp?

Also, can you post a pic of the underside?


KGB

pqrannes
07-30-2009, 03:09 PM
What's that object between the "Treble" and "Bass" knobs?

Is that a power indicator lamp?

Also, can you post a pic of the underside?

KGB

Which amp are you referring to?

I don't have other pictures than the ones in the auctions (which are not mine).

Pictures of the underside of my amp are to be found earlier in this thread.

PQR

similost
07-30-2009, 03:18 PM
That's a tuning eye tube.. no idea why it's on that piece though, because there isn't a tuner that I see of... interesting.. maybe using it as a power level indicator?

Ty_Bower
07-30-2009, 03:22 PM
Cute little amp. I've got one almost exactly like it. Mine was labeled "XAM Mark IIIb", or something like that. I think it was sold in the EJ Korvette stores way back when. I gutted the nasty tone circuit out of mine, and added in a volume knob. It's a perfectly serviceable amp. One of these days I'm going to strip it down completely and rebuild it into an RH84. I've also seen the same amp under the "American Fidelity" name, except it didn't have the vacuum tube rectifier. They converted the supply to solid state diodes at that point.

http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_xam.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/xam.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_P1070379.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/P1070379.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_P1070359.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/P1070359.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_EL84ampv3.gif (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/EL84ampv3.gif)

Sam Cogley
07-30-2009, 03:26 PM
That's a tuning eye tube.. no idea why it's on that piece though, because there isn't a tuner that I see of... interesting.. maybe using it as a power level indicator?

Maybe a balance indicator?

pqrannes
07-30-2009, 03:56 PM
Cute little amp. I've got one almost exactly like it. Mine was labeled "XAM Mark IIIb", or something like that. I think it was sold in the EJ Korvette stores way back when. I gutted the nasty tone circuit out of mine, and added in a volume knob. It's a perfectly serviceable amp. One of these days I'm going to strip it down completely and rebuild it into an RH84. I've also seen the same amp under the "American Fidelity" name, except it didn't have the vacuum tube rectifier. They converted the supply to solid state diodes at that point.

http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_xam.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/xam.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_P1070379.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/P1070379.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_P1070359.jpg (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/P1070359.jpg) http://i69.photobucket.com/albums/i43/Ty_Bower/Tubes/th_EL84ampv3.gif (http://s69.photobucket.com/albums/i43/Ty_Bower/Tubes/EL84ampv3.gif)

Nice info and an interesting project.

I guess I'll keep mine original since I'm very pleased with it at the time being.

The multi cap in the power supply got bad earlier this year (the amp started to hum) and I changed it.

Then a month ago I changed the input tubes from Philips to Telefunken ECC83s and used a much bigger and heavier 220V--> 110V stepdowner.

What a difference!

These two upgrades gave me an amp with a much better grip of the bass and a more distinct high as well. I'm very very pleased with this little SE amp!

PQR

KGBMAN
07-30-2009, 04:54 PM
Which amp are you referring to?

I don't have other pictures than the ones in the auctions (which are not mine).

Pictures of the underside of my amp are to be found earlier in this thread.

PQR

Thanks, I missed the entire segment with the underside photos.

The object I was referring to is depicted here:

pqrannes
07-31-2009, 12:51 AM
Thanks, I missed the entire segment with the underside photos.

The object I was referring to is depicted here:

In that case, you are right. It is a power indicator light. Not the most beautiful one, but one that works!

PQR

endangered
04-03-2014, 01:25 PM
hi all , i just picked up two shell electronic 2020p amps really cool amps i also call them my cyclops amps because of round cats eye tuner type tube in top middle of amp. its to show input level as far as i can tell probably so you don't overdrive/distort the amp . although i hear no distortion when i input power so the tube eye is closed or is that open lol?! ones in reply pretty good shape the other has a bit of oxidation going on . sounds pretty darn good powerful little amp . i am going to send out to tech to have a go over as it starts to hiss a little bit when warmed up. drives my restored ar 2ax speakers very well though. best tom

pqrannes
04-03-2014, 02:26 PM
hi all , i just picked up two shell electronic 2020p amps really cool amps i also call them my cyclops amps because of round cats eye tuner type tube in top middle of amp. its to show input level as far as i can tell probably so you don't overdrive/distort the amp . although i hear no distortion when i input power so the tube eye is closed or is that open lol?! ones in reply pretty good shape the other has a bit of oxidation going on . sounds pretty darn good powerful little amp . i am going to send out to tech to have a go over as it starts to hiss a little bit when warmed up. drives my restored ar 2ax speakers very well though. best tom

Congratulation on the two fine Shell amps.

Mine had the OTs (output transformers) changed since one burned out and it never came back to former magic; it is now a museum artifact here in my hi-fi room.

Good luck with your amps.

PQR

Brian
04-03-2014, 03:35 PM
Hmmm... My first thought was that now I know where AR got the look for their original amp from.

endangered
04-05-2014, 07:00 PM
hi all , sorry bout an amp becoming a shell of what it was .... pun intended not so well ... ha !
i have one shell to nos valve and hope for the best .and thats the one in decent condition. the other is cosmetically a bit more pitted/corrosion and not sure how it kicks on . thats with a different tech at the moment but that may change quickly .
don't know about you all but since my fiddling days are at near end it seems mighty difficult to find someone that really cares enough to go the extra mile to fix stuff. thats why i am counting on nos valves . heard nothing but good stuff.

endangered
04-05-2014, 07:00 PM
ar looks nothing like a shell amp