Grundig Powered Speakers Repair - 1961

Two Grundig Powered Speakers from 1961 blowing fuses and getting way too hot. They are also designed to operate from a 220 Volt power supply and need to run on about 240 Volts. I will have to change a few things around to make them work. I cannot find any info on this exact model but found a circuit for a similar model, "Grundig Stereo Verstärker Box IV\V" which I think is the previous model with a single speaker.
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[@boballmendinger3799]

Those are a sweet piece of mid century life! Thanks for saving them.

[@DavidTipton101]

I agree Bob. Thank you 👍🙂

[@videolabguy]

Simply the best restoration channel on KZbin. Always a joy to watch your work and your creative process to problem solving.

[@DavidTipton101]

Thank you videolabguy👍😀

[@kimhenry5658]

Hi Dave, I enjoy fixing things but you are at that next level called “fearless”. You’re an inspiration. Cheers from Tasmania.

[@DavidTipton101]

Hi Kim, thank you. We are in Melbourne for a few days, not 'that' far from you 😄

[@stevescheberle277]

Thanks Dave, another riveting video from down under!

[@techman2471]

Dad joke, good stuff!😝

[@DavidTipton101]

Haha... I see what you did there 😄 thanks Steve.

[@BoB4jjjjs]

Now there is a product I never knew existed! Your humour is still the same 😂 I am surprised you didn't have a go at the cabinets!

[@DavidTipton101]

Me neither Bob. The owner didn't ask for the cabinets to be done which was just as well 😄 Thanks Bob.

[@terryblackman6217]

Thank you for another very enjoyable video. Folklore has it that Vegemite is very good for freeing up frozen potentiometers. Thanks again David. 😆👍

[@DavidTipton101]

Hi Terry, Vegemite in potentiometers! Is there anything it can't do? Thanks Terry 😂

[@Peugeot306]

Oh yeah. A new Tipton!

[@DavidTipton101]

Thanks Paul 😀

[@Harryset1]

Now these are very rare birds - i'm sure i did not see this "Grundig Aktiv Boxen" in the last 40 years -- you did a very good job -- now they are ready for daily use again - As always all the best from Germany -H.

[@DavidTipton101]

Thanks Harryset1. They should be good for quite a few years. Cheers 😀

[@Harryset1]

@@DavidTipton101 Again : Great Job! There more mysterious ways then we can think of -- somebody must have loved the Grundig speakers for a very long time -- build in the early 60s of the last century - over here in Germany - and there is a long way to go for two harmless speaker boxes -- to end up on your workbench so far away -- now good to play for the years to come!

[@4X6GP]

Absolutely my favorite channel. Your videos always are novel, either technically or from an entertainment standpoint. Please keep doing them!

[@DavidTipton101]

Thank you Victor 👍😀

[@dogribmoon]

Those speakers need to be in a swinging bachelor’s pad! Groovy David, just groovy.

[@DavidTipton101]

Perfect! I wish I had thought of that for the video. Thanks Austin... err... I mean dogribmoon 😄

[@alpcns]

I didn't know that these old, smoking hot capacitors can develop so much thrust - flying speakers in spaaaace! Courtesy of the Tiptonian cap drive™! Thanks for another enjoyable restoration episode. Great work!

[@DavidTipton101]

Yes, surprising isn't it. NASA or Space X may be interested in the technology 😄

[@richb419]

Hi David, Just a tip, I found that I can grab a round shaft very well with an old drill chuck tightened against the rod with very little damage. good luck Rich

[@jeffreyhickman3871]

I just saw ya over here 👈 on Don’s Old Radio 📻 Shed. It was so interesting 🤔, seeing your comment there. He was resurrecting a very beautiful 😍 floor model radio 📻. They are actually furniture 🪑. From glass dial faces to dial lights. Built out of wood 🪵, and fine quality speakers 🔊, they are truly a GREAT 😊 radio 📻. Even he (Don), deals with the good 😊 stuff. Your friend, Jeff.

[@DavidTipton101]

Thank you Jeff 👍🙂

[@1959Berre]

Hi David. Great job. Only a genuine restorer disassembles a pot meter and rivets it back together. I like that commitment. Nothing compares to the glorious sixties, when my late mother was young and beautiful.

[@DavidTipton101]

Thanks 1959Berre. I got a bit excited with dismantling the pot 😂 we were all young and beautiful back then 🙂

[@JerryEricsson]

It was indeed a time of love, a time of magic and before health took over. We smoked those cigarettes till they were so short we needed tooth picks to hold them, we drank so much beer that, well a lot of beer, and some folks smoked those funny smelling cigarettes that they rolled themselves. The music was transforming and sex was wonderful and free. Wow if I could only go back for a day...

[@jonka1]

@@DavidTipton101 Well I was younger for sure!

[@badscrew4023]

Ah, the resistors with actual values printed on them. Soo good to see those.

[@DavidTipton101]

It makes it easier 😄

[@philllynch3265]

HI Dave. I remember speakers like that !!!!!. That was 62 years ago. Oh I feel old LOL. Take care , good job . Hi to Karen

[@DavidTipton101]

Really, I don't recall seeing anything like it. I was 7 when these came out. Take care, I'll pass on to Karen 👍🙂

[@philllynch3265]

@@DavidTipton101 Hi Dave. I was 10 then. Our rich Italian neighbors had something similar . Can't remember the make, but I do remember the controls were on the speakers. which I suppose by deduction they were powered. What do you think?.

[@DavidTipton101]

It would be safe to assume they would be powered Phil 👍🙂

[@philllynch3265]

@@DavidTipton101 Thanks Dave

[@billharris6886]

Hi Dave, thanks for another interesting restoration video. I actually remember seeing those speakers being sold growing up in the early 1960's in Florida in the US. The German HiFi systems didn't sell very well here, although the mantle radios did. I think the Philps valve set was one of the reasons, as RCA (Radio Corporation of America) dominated all the valves here, and were what people were used to seeing. In this particular instance though, the ECC83 is the same as a 12AX7, and the EL84, the 6BQ5. Concerning the resistor in series with the power transformer primary, I do that with every antique radio I restore for the following reasons: (1) The power companies have been increasing their mains voltage over the years. In the 1960's, the mains voltage used to be 110 volts but now, it is 118 to 127 voltage (depending upon the time of day). (2) The resistor acts as a fuse, surge protection, and improves the power factor. (3) A resistor is of course mandatory if you are replacing a selenium or valve rectifier with silicon diodes.

[@DavidTipton101]

Thanks Bill. There was a setting for 120Volts I think I remember so nit surprising they showed up in the US. I agree with your thought with the resistor 👍😀

[@nathkrupa3463]

Great job David sir nice. Sir you use a grease on pot meter log apply surface area on log no problem volume control no irritating sound. Thanks for sharing this video I really enjoyed the show.❤❤

[@DavidTipton101]

Ok, thanks Nath, I'll keep it in mind 👍🙂

[@xyredmax]

Hmm, a new sideline 'Daves Pot Shop' 😋 Nice work, as usual, BR Mark

[@DavidTipton101]

Thanks Mark, I assume you are referring to potentiometers when you say 'pot' shop 😄

[@richardbrobeck2384]

Dave those are some really beautiful speakers and the amplifiers turned out really nice !

[@DavidTipton101]

I agree Richard. Thank you 🙂

[@nathanmoak1515]

they sound better than anything we had in 1961! we had an admiral 19" b&w tv with built-in am radio and turntable.

[@DavidTipton101]

The Admiral TV/gram sounds nice. It would have been exciting back then. Thanks Nathan 🙂

[@domtrimboli6238]

Hi David, your work is first class and a pleasure to watch cheers.

[@DavidTipton101]

Thank you Dom 🙂

[@Antony_Jenner]

Bit late to this party but those powered speakers a awesome, good work Dave!

[@DavidTipton101]

Thank you @alast3897 👍🙂

[@horatiohornblower868]

„Even if it doesn’t work, it looks cool” Another vintage Dave Tipton! That’s why I like your channel so much, Dave!

[@DavidTipton101]

Haha... that sound's like me 😄 Thanks Horatio Hornblower 🙂

[@superhet7281]

Excellent work, Dave! Psycho, Fonzie and Vegemite - an unbeatable combination!

[@DavidTipton101]

Haha... thanks Super Het 😄

[@phillipyannone3195]

Another excellent repair. Love the heat syncs and the resistor brackets.

[@DavidTipton101]

Thanks Phillip 😀

[@stevensansone7502]

Another "Started the video just after midnight" with the dulcet sounds of Mr. Tipton. The next thing I know, it's 3:20 a.m. and some dude is working on an old TV. He wasn't being very 'soothing' about it, either. Which, now that I think about it, might account for the tobogganing on gravel dream.... Anyway, I restarted your vid first thing this morning. Didn't even bother waiting for lunch time. It was the correct choice. Great work, sir. My actual life can wait. I've got some Radio/Speaker Adventures to begin the day with. And coffee, too. I'm not completely out of my mind.

[@DavidTipton101]

Haha... been there Steven 😂 Thank you Steven, you have to get your priorities right 😀

[@Jon_Ericson]

Thursday night at 1AM. Hello Dave!

[@DavidTipton101]

Wow, that's late. Hi and thanks John 😀

[@nzs316]

What is truly to be remarked is how people are reverting back to old hifi tech. If you had grown up with those old turntables, receivers and the deep rich sounds from those massive speakers. Then you can understand why people are putting aside their algorithmically reproduced sound from their smart devices and discovering how music was supposed to sound like. There’s a certain magic to flip a switch and watch the vacuum tube or valve warm up and the sound come to life. Everybody should at least once in their life, rent a cabin or go camping in the woods far from anything and just bring a transistor radio with you. Years back I was doing some logging on the river and I had an old car radio hooked up to a battery with a speaker attached to it for entertainment. There used to be a program called “lovers strangers and other things”where every evening they would have a story that would last half an hour or an hour. I loved listening to those shows with no diversions or distractions and the flames flickering on the walls from the wood stove.

[@DavidTipton101]

Hi Neil, it seems to be the way doesn't it. I used to curl up in a big chair as a child and listen to our old console radio with the wood fire next to me. Good times. Thanks Neil 👍🙂

[@electronicsoldandnew]

Great project. This are really nice little amps. Thanks for the video.

[@DavidTipton101]

Thank you Manuel 👍😀

[@js0000356]

Nice to see those working again! The electrolytic caps usually have a metal closing cap on them right in the middle where the holes are, when they are gone it's usually a sign the electrolytic are in a terrible state and have vented

[@DavidTipton101]

Thanks Jurriaan 👍🙂

[@daShare]

To convert a 220V item to 240V, you can also use a 240V - 20V transformer to reduce the voltage. That would get you most of the way there with no extra heat in the chassis.

[@michvod]

You can use a small wall 240V-12V wall wart and wire it like an autotransformer, but out of phase, so the voltage will be subtracted instead of added. So you will be getting 228V output, but if you can find a 240V-20V, then you will get a perfect 220V at the output.

[@daShare]

@@michvod Just to be clear, it needs to be an AC output plug pack (wall wart), not a DC type. Keep in mind that the rating of the secondary winding needs to be rated for the worst case current draw of the 220V output.

[@michvod]

@@daShare has to be an old school type with 50hz transformer. If it is sealed and has a DC output, then it can be opened and the DC rectifier removed

[@DavidTipton101]

The transformer idea has merit, it would depend on cost and room to mount it in some cases but a neat idea. Thanks da-Share 👍🙂

[@ibrahimkocaalioglu]

nice episode. good to see repairs other than radios.

[@DavidTipton101]

I agree, thanks Ibrahim 👍🙂

[@leif.Jakobsson]

Thank you David, Very interesting and very nice job! As a child of the 60's (66) I prefer old school vs todays compressed BS...

[@DavidTipton101]

Thank you Leif. Agreed 👍😀

[@RocRizzo]

Very nice restoration. I especially liked the video montage at the end.

[@DavidTipton101]

Thank you Rocco 😀

[@JacGoudsmit]

I notice it uses a lightbulb to show that the power is on. I suppose instead of resistors to "toast" the extra voltage away, you could have rewired the power-on lightbulb in series with the primary or B-plus circuit to give it a built-in over-current protection / short circuit check / voltage dropper. 😄 Great video as always! Thanks for posting.

[@DavidTipton101]

Hi Jac. You can use a bulb to lower current and lower the voltage and it was done in the past. The bulbs were called Barretters' and I think used in the filament string but I'm not sure. They only glow dimly like my dim bulb current limiter. Thanks Jac 🙂

[@erikdenhouter]

"Split chopstick with sandpaper...", the autumn recipe from David 👌🏻You want Tipton tea with that ? In our supermarkets there's vega 'chicken' stuff without chicken, and on the package it says: "Happy chicken". But which non-existing chicken will be happy ? Is that what they mean by "You'll own nothing and be happy..." ?

[@DavidTipton101]

Haha... I guess every chicken that is not in the packet would be a happy chicken 🐔😀

[@markvanmaanen5152]

I've had the exact same experience with old sewing machines. Lubricant turns into glue, you heat it up and it loosens up beautifully, but as it cools it just hardens straight back up. Just by keeping it hot and moving and adding thin oil you can eventually wash out and replace the old stuff. I do like the originality of the old pots, weird design as they are. Greetings from the Netherlands!

[@DavidTipton101]

Hi Mark, it's the same with turntables too but you can usually dismantle them to remove the old grease. I heated and soaked the other three for ages before they would free up. The design was unusual but a pretty good solution rally 👍🙂

[@erikdenhouter]

I had the same trouble with a '50 microscope. It is just the fact that they are not used. If they were used the stiffness would be noticed on time and a little oil would help out for the next 40 years.

[@clasicradiolover]

Hello, Dave. Good to see another great video. That type of "wood" ruined furniture and antiques in my opinion. My wife had a console from the 60s or 70s made of that stuff. She wanted to ship it to you. My area is very humid, however and it didn't survive. It's now composting our garden.

[@DavidTipton101]

Hi clasicradiolover, what a shame about you consul radio. Particle board loves... or hates water and moisture. It also tends to dry out where it hasn't been painted and simply chips off at the edges. I backfill the edges with PVA glue to prevent further chipping. Thanks 👍😀

[@rewalton46]

When you started on the tone pots, I thought sure you were dealing with expanding pot metal. That is what it looked like on my screen. It was a great relief to know that the housings were cast aluminum. I really liked your slotted chopstick as a hone. I'll have to remember that. Great job, as always!

[@DavidTipton101]

Hi Rick, if they were pot metal they were well made but I think they were aluminum, they took a bit of stress while I got them working again. It was slotted dowel but a chopstick would work also. Thanks Rick 🙂

[@jonka1]

Kebab skewers work for small holes.

[@kennethconnors5316]

Your patience doing this is impressive ,,

[@DavidTipton101]

Thank you Kenneth 🙂

[@michaelclutton8446]

Hi David, I have never seen speakers like that in England, nice repair.Regards Mike

[@DavidTipton101]

Thanks Mike. This was a first for me too 🙂

[@bobpotter895]

G’day Dave. I think one of the first times I heard stereo was at friends of my parents house on a system very much like these. It was a record of a train going past with the wonder of the sound going from one speaker to the other. Seemed very fancy in the early 1960s. I guess it was easy to impress me back then.😉

[@DavidTipton101]

Come to think of it I didn't have anything stereo till the mid 70s. FM didn't come in till then and we bought a stereo record player when we were married. Everyone has heard the train record 😂 Thanks Bob.

[@jeffreyhickman3871]

Just saw your video pop up. That Grundig is the ‘57Chevy Bel Air of radios 📻, with the “V”. I’m going to guess that this radio 📻 is also 1957. I think 🤔 the speaker 🔊 is permanent magnet 🧲. Capacitors are always the issue with these older radios 📻. Just DON’T wire the capacitor 🆙 backwards. If ya do, on the “click” to “ON” with the volume knob, “POP”, will go the capacitor. This can blow many 👨 capacitors, it can blow one ☝️. It will be a LOUD “POP”, and it will scare the heck out of ya. I’m wondering about the dial light 💡, and the dial cord. Just don’t burn 🔥 the dial cord in half with your soldering iron. Your friend, Jeff.

[@DavidTipton101]

Hi Jeff. Thanks for the tips. I don't think there will be an issue with the dial cord on this one but I'll keep it in mind. Cheers 🙂

[@samuelfellows6923]

🤨 They weren’t radios ~ powered speakers from the 60s

[@myfarawaytales]

Nice one Dave! Mega interesting as usual. I like it when you make incremental improvements until it's near perfect.

[@DavidTipton101]

Thank you Paul 👍🙂

[@CXensation]

That basic ECC83/EL84 amplifier was my first school project back in the 60'es. The year after I upgraded to a stereo push/pull amplifier using some salvaged parts from around. I remember the power transformer was a bit too high on the plate voltage winding making the 4 EL84's glowing red hot on the plates. Solved using series resistors. Then suddenly the (salvaged) rectifier electrolytic tried taking off like a rocket. It could not withstand the too high plate winding voltage. I got the power transformer and one speaker transformer from an old rusty push/pull EL36 amplifier chassis stored in an old radio shop. By sheer luck my father found a second speaker transformer exactly the same type from a radio amateur. Sadly these projects got lost over the years during many times family moves ...

[@DavidTipton101]

Hi CXensation. That's what we did back then, scavenge around to find bits and pieces to make something. Good story CXensation, thanks 🙂

[@philbooth1511]

HiDave, I certainly remember those Grundig active speakers. Those Grundig amplifiers (EL84 & ECC83) were very much tried and tested. The earliest versions, or variations I encountered (with EZ80 rectifier) was from 1957, though I might have heard 1954 - year thee 'n' me first saw the light of day LOL. Like you said, the rectifier valve was replaced with solid state rectification around 1959/60. I have a feeling variations of that amp was manufactured through to 1965 - Manuel will probably know more about them more than I do. I personally like those active speaker cabinets but I agree with you, they are not true Hi-fi. They deliver a pleasing sound - that which would be typical from a high-end stereo radiogram. Lovely talking to you my friend, Phil.

[@DavidTipton101]

Hi Phil, thank you for the info on Grundig speakers. Yes, they sounded like a radiogram from the 60s, nice to listen to all the same. Thanks Phil 🙂

[@markbrownfield437]

Those speakers looked and sounded groovy! Enjoyed your video, as always! Cheers from Oregon

[@DavidTipton101]

Thank you Mark from Oregon 🙂

[@gordonlyon2351]

another great video Dave - your attention to detail is inspiring!

[@DavidTipton101]

Thank you Gordon 🙂

[@hestheMaster]

That was an awesome repair Dave! Such commitment to pot repairing is inspiring.

[@DavidTipton101]

Haha... thanks Steve, I'm glad you were inspired 😀👍

[@MCML50]

Hi David, It was nice to see a brand new video from you. Greetings from Sweden.

[@DavidTipton101]

Thanks you Claes. Greetings 🙂

[@ellesmerewildwood4858]

60's tech but they still sounded really good. Mind you, there are speakers made with modern tech that sound awful. Chipboard, the bane of every piece of furniture ever built. Did you get a look at the condition of the cones ?

[@DavidTipton101]

Hi Ellesmere. Yes, chipboard... it was attractive to the industry but any moisture and it's kaput. I checked the speaker cones, they were good. Thanks Ellesmere 😀

[@SuperFireeater]

Always enjoy your “Adventures” Dave… Jim from Pensacola, Florida…

[@DavidTipton101]

Thank you Jim from Pensacola 👍😀

[@mikecass8306]

Another great repair as usual, thanks David. 🙂

[@DavidTipton101]

Thanks Mike 🙂

[@kensherwood4866]

Welcome back with something different. Interesting as usual, great to follow your logical problem solving. Cheers and best wishes

[@DavidTipton101]

Thank you Ken 🙂

[@birdie399]

Thanks DT for an interesting adventure. I always enjoy your fabrication work. Also some nice animations.

[@DavidTipton101]

Thanks birdie399 👍🙂

[@JerryEricsson]

Cool indeed, wish we could find such items here in South Dakota. Enjoyed the tear down of the sticky restate.

[@DavidTipton101]

Thanks you Jerry 🙂

[@brianwood5220]

Nice job Dave, have a great weekend. Thanks for sharing.

[@DavidTipton101]

Thank you Brian. Have a good weekend yourself 🙂

[@wayneshirey6999]

Nice work, Dave. I was hoping you'd tackle the cabinets.

[@DavidTipton101]

Thanks Wayne. The owner didn't ask for the cabinet to be done 🙂

[@mackfisher4487]

Dave you always take us on a great radio adventure. I couldn't hear what the speakers were like only you could, but for such a big cabinet you'd think a manufacturer could come up with something really outstanding. I'm sure the owner is happy to have them working again.

[@DavidTipton101]

Thank you Mack. The last bit was recorded directly from the speakers using my mic and they sounded like 60s speakers. They sounded similar in the room as well. The owner was very happy to have them working again 🙂

[@jonka1]

In the 60s few people were audiophiles due to the limitations of the tech and the cost relative to income. I suspect those speakers were bought for style rather than Hi Fi quality. A friend's father had some of the first electrostatic speakers driven by a Nad amp but he was using a deck from a dansette as he had no money left for anything better.

[@aerofart]

You might want to consider listening to the presentation using a good set of earbuds or headphones. You’d be amazed at the detail you can hear. I always listen to shows with earphones - unless the production audio quality is so intolerable that losing some fidelity turns out to be a benefit.

[@Daniel_cheems]

Another overengineering project, but all for a great cause. Well done Dave and great to see you again!

[@DavidTipton101]

Yep, overengineered to the MAX! 😄 Thanks Daniel.

[@genestatler2514]

Beautiful work David. Love your videos. Gene from Tennessee.

[@DavidTipton101]

Thank you Gene from Tennessee 😀

[@craignehring]

Very nice eh? We learn by doing!! Nice touches on this one David.

[@DavidTipton101]

Thank you Craig 🙂

[@chrissmith7655]

Hi Dave good stuff as usual , many thanks from UK.

[@DavidTipton101]

Thank you Chris in the UK 👍😀

[@greengrayradio1394]

Very good, David! I have struggled with tuning capacitors (attacking the dreaded dial cords..) and pots from 60's to 70's exactly as you describe here. They must have used a special kind of grease which turns into glue nowadays. Strangely, I haven't encountered this in older equipment (or newer). In my experience the best thing is to dismantle the shaft from the bushing (as you showed), clean well and re-lube. if only softened with solvent, it will re-stick in a week or two. At it again.. Nice 60's show also!

[@greengrayradio1394]

Found in pots and variable caps from Western Germany in that period

[@DavidTipton101]

Thank you greengrayradio. Dismantling is the better option but they did free up with an large of solvent and a re-oil. I hope they don't bind again as you suggested. Glad you liked the 60s show 😀

[@CraneofBoulogne]

Great work Dave, as usual!

[@DavidTipton101]

Thank you Jeff 🙂

[@LarryDeSilva64]

Don't know what happened David but you made a comment and told me Shango had done the same G.E. E50 radio. which you were totally right it was exactly the same radio. For some reason your comment showed up in my notifications but not in the comments of my video. Thanks for checking for me and you are also right the same exact tuning dial cord was used. Thanks LL

[@DavidTipton101]

Hi LL, I had a link to Shango's channel in my comment so it may have been deleted or moved into 'held for review' in KZbin studio. Anyway, that should help with your restringing. It was a wonder I remembered Shango doing it 😀 Cheers!

[@LarryDeSilva64]

@@DavidTipton101 Yes I saw it david and found that indeed he did do the same model E50 radio thanks.

[@ceebee23]

oh David you jut love the different!!! great job as always!

[@DavidTipton101]

That's me... 😄 Thanks Chris.

[@derrickgoodwin7078]

Hi David. Another good video. Enjoyed it. Keep em coming. Derrick.

[@DavidTipton101]

Thank you Derrick 🙂

[@grugbug4313]

Solid! Top KEK! Peace be with you.

[@DavidTipton101]

Thank you Grug Bug 👍🙂

[@boinkmiguel]

always enjoy watching

[@DavidTipton101]

Thank you Wally 🙂

[@brianyoung9014]

Nice work David, interesting set of speakers.

[@DavidTipton101]

Thank you Brian 🙂

[@iantyler4045]

Once again a very enjoyable video. Your attention to detail is always amazing. Getting all the voltages just right after a rectifier replacement. It will now last for many years.

[@DavidTipton101]

Thank you Ian. Fingers crossed for reliability 🙂

[@LockdownElectronics]

Another excellent job!

[@DavidTipton101]

Thank you Lockdown 🙂

[@pcno2832]

1:08 That's an interesting output stage. Normally, the idle current of the single-tube would partially saturate the output transformer, limiting the bass headroom. But here, they seem to be feeding the current for the rest of the circuit in the opposite direction, perhaps to cancel that DC bias without having to spend the money on a push-pull output stage or a bigger transformer core. I figured someone would have done this at some point.

[@DavidTipton101]

Could be @pcno2832. I thought it was being used as a choke for additional filtering. It does make a Pi filter capacitor - choke - capacitor 🤔🙂

[@rciancia]

Dave - the method you used on those Pots was nothing short of brilliant !!!!! Excellent job overall as usual !!

[@DavidTipton101]

Thank you Ron 👍🙂

[@senorcapitandiogenes2068]

The potentiometers seizing up is common with Grundig equipment of that time. Flushing them several times with turpentine usually gets them going again after a few rounds

[@DavidTipton101]

Hi @senorcapitandiogenes2068, I can imagine Grundig caps of of that period will suffer the same problem. The solvent in WD40 is not that far from turps and is a hydrocarbon version in white spirit. Whatever, they did not move without heat to allow the solvent to get in there. I will know next time. Thanks @senorcapitandiogenes2068 👍🙂

[@kahlid-ataya]

thanks for the Eid gift 🎁 you made my day

[@DavidTipton101]

My pleasure خالد عطايا 🙂

[@garfieldsmith332]

A very interesting video. I had a Grundig reel to reel in the 60s. I was surprised to see the inside electronics. They looked kind of hap-hazard in assembly. It was not what I thought Grundig electronics would look like. Great that you got it working. It does sound good.

[@DavidTipton101]

Point to point assembly often looks messy doesn't it ? In reality it is carefully laid out so components don't cause interference to other components. Some manufactures do it better than others though. Thanks Garfield 👍🙂

[@garfieldsmith332]

@@DavidTipton101 I would take it that it looks messy because of no circuit board of some type. As you said point to point. My UHER Report tape recorder looks a lot neater, but everything is compacted into a smaller area and they have different functions. Still German quality. I come from the time when the big European electronics companies had the market; Grundig, Uher, Phillips, Tanberg, Telefunken, etc. Still like the look of them today. And as for quality. my Dual 1209 from the 60's is still in use.

[@skip1835]

crazy impressive - another home run - - thanks David

[@DavidTipton101]

Thank you Skip 😀

[@OIE82]

Like and Sub. Mostly because I appreciate your ingenuity (brackets, pot disassembly, etc.) But, let's face it, you have a cool accent and that helps. 😉

[@DavidTipton101]

Haha... thanks Luther 😄

[@markpirateuk]

These are very rare in Europe, let alone Australia, I was hoping for a push-pull amp rather that a single ended design, but I guess that was deemed adequate for domestic use back then. Very similar construction to the huge Grundig WE5077 radio I just restored (push-pull EL95 output), the red resistors in my set were all well within tolerance, looks like yours were also good. As always, I love your attention to detail, the added heatsinks were a great idea, my set actually had aluminium heatsinks on the mains transformer from the factory, never seen that before!

[@DavidTipton101]

Hi Mark. I bet there aren't many of these speakers in Australia, these would have been imported. I don't think I have seen a EL95 in a set here, similar to the 6BM5 I think. The resistors were very accurate. Heatsinks on a mains transformer, I haven't seen that either 🙂

[@markpirateuk]

@@DavidTipton101 I have a love/hate attitude to Grundig, although they do sound good, they are a nightmare to service, components that are buried away, complex tuning arrangements, over complicated pushbutton assembly's & electrostatic tweeters that are always dead! The EL95 (aka 6DL5) is not a common valve over here either, thankfully both on my set tested good, although the expensive EM34 is pretty dead :( Still have three Grundig sets awaiting restoration....

[@craigbrown7929]

@@markpirateuk tell me about it. I just recapped a grundig console a few months back. It was a pain to get to the chassis bolts and even worse to get the chassis back in.

[@bertroost1675]

I have something like this in my basement. It isn't Grundig but it is German. The tweeter is missing but the amp and woofer are inside. The cabinet is in pretty good condition. If we were in the same country I'd give it to you because I think you could make it good again.

[@DavidTipton101]

Sounds like an interesting project for someone. Thanks Alan 🙂

[@magcoco]

Very nice speakers. Great job ❤️

[@DavidTipton101]

Hi Khaled, thank you 🙂

[@josephmagedanz4070]

That was interesting and something new. Plus good tips as usual..thanks!

[@DavidTipton101]

Thank you Joseph 🙂

[@Leo6009]

Nice job on the honing. I was trained at TAFE NSW, to clean up an engine cylinder using that basic honing technique 40 years ago. The setup was very similar, running a wooden rod with a slit and a flap of honing paper, left loose to hone the cylinder via the centrifugal force, using an electric drill. My honing skills developed quite a bit since then. I was quite impressed in your resourcefulness with the rivets David. Any chance of getting the exact name of the product, so I can run a search. The rivets often give way in the German radio rear cover locking wheels that rotate into locking the cabinet rear door into closed positions. A good few worthy techniques provided in the Radio Adventure. 👍 I can’t wait for your next Radio Adventure! 🔧😁

[@DavidTipton101]

Hi Pete, thank you. The honing technique is used all the time in engineering and often used to remove paint from bolt holes after repair. Do a Google search for "Hollow Rivets" and you will find lots of options 🙂

[@Leo6009]

@@DavidTipton101 my family certainly has had their involvement in engineering, having completed a major contract at one stage in components supply and components installation, for the Anzac Bridge construction in Sydney, when it was being built, not to mention the 20 odd houses we built just to mention a few. There are plenty of rivet kits and various sizes around but I was more interested in the kit you showed due to the smaller sizes.

[@Leo6009]

It’s all good, I sorted it!

[@maartenschapendonk6345]

Love your work. Have had a raumklank speaker once. Added bluetooth and it sounded amazing.

[@DavidTipton101]

Thanks Maarten. I haven't heard of Raumklank, interesting 🙂

[@maartenschapendonk6345]

@David Tipton you're correct raumklang were normal speakers from Grundig. The one I had was a GRUNDIG Stereo-Verstärker-Box. Similar but with power amplifier

[@DIlic-iz9tx]

_David, I enjoy watching you. You are the best of the best._

[@DavidTipton101]

Thank you Domenico 👍😀

[@MarkMcCluney]

Always a treat and always an education. I mean, who knew about Chicken a la Vegemite? So. How did it taste? Cheers Dave, very enjoyable video.

[@DavidTipton101]

I like to cover all aspects of radio restoration including the dietary habits of the author 😄 The chicken tasted like roasted chicken with the occasional hint of Vegemite, not worth the effort really. Thanks Mark 🙂

[@billnicholson2470]

Nice job David. I love the creativity you add to your repairs. Your engineering skills are incredible. 73 de KB7ICI.....Bill

[@DavidTipton101]

Thank you Bill 🙂

[@fibberscloset498]

Always fun, David. Thanks!

[@DavidTipton101]

Thanks Fibber's Closet 👍🙂

[@haythamchannel3553]

Hi David as usual great job

[@DavidTipton101]

Thank you Haytham channel 👍🙂

[@davidahart2476]

Hi Dave, My dad's first reel to reel was a Grundig, it was a suitcase type.

[@DavidTipton101]

Hi David, I also have a Grundig reel to reel 🙂

[@davidahart2476]

@@DavidTipton101 He went from the Grundig to a Teac to a Akai 747 which I still have, The Akai has glass heads which need to be cleaning but not sure how to do it.

[@kennethgibbons366]

Well done David... - a few little probs for you to solve. Interesting how you sorted the control pots... I wonder how they ended up being solid - was it oil/lubricant that had gone hard. I'm sure that in its day it (they) were considered very cool.

[@DavidTipton101]

Greeting Kenneth. The grease used back in the day dries out and leaves only the hard "wax" component. The wax makes a pretty good adhesive apparently and being wax responds to heat. It's the same with 60s turntables, heat will loosen the parts so it can be dismantled. I bet many drooled over these speakers in the 60s but could never afford them 🙂

[@top40researcher31]

hi david i remember seeing this brand as a video cassette player

[@DavidTipton101]

Hi Top 40 Researcher. Grundig made an enormous range of electronic and appliances so not surprising you would have seen some of it 🙂

[@top40researcher31]

@@DavidTipton101 back in the 1980s and 90s yes i have

[@paulbache3940]

interesting work, thanks David

[@DavidTipton101]

Thank you Paul 😀

[@_-_Michael_-_]

BTW those pots were made by German PREH company and same ones were used in Hofner made guitars in 60s most memorable one that has the same pots inside would be 500/1 bass that Paul McCartney from The Beatles plays since 1963 he still uses his original one till this day. They often get hard to move and they were considered unrepairable if they are way too stuck and not movable with heat or lubricants. Now you kinda pioneered repairing them. Cheers mate.

[@DavidTipton101]

I always wanted to be a pioneer, thanks _-_Michael-__ 👍😀

[@RajeshSharma-wy5jl]

Good work ❤

[@DavidTipton101]

Thank you Rajesh 🙂

[@camhyde9701]

they do sound quite good... got that warm 60s valve sound... interesting to see self-powered speakers have been around much longer than i thought

[@DavidTipton101]

They sounded Ok... not as tight as modern speakers but suited the period. Aside from woofers I'm struggling to think of any other self powered speakers 🤔🙂

[@kilcar]

Brilliant. Thanks very much!

[@DavidTipton101]

Thank you Patrick 😀