New project: Telefunken ELA V306 tube amp

[Hotzenplotz]

About 10 years ago somebody gave me this amp for free. It was from our local university that wanted to throw it away, just because it was not needed anymore and it was looking old!!! Until yet it was just a "nice thing", some decoration in my living room. - But why?!, I ask myself now, too.

It is a Telefunken ELA V306, made in autuum 1957! I plugged it already in and all tubes start to glow the way they should. These ELAs are 100V (!) speaker technology. 100 Volts were used for the reason of looooooong cables in big rooms. Fortunately I found somebody that wants to give me two perfect fitting 100V boxes.

The output of this amp is 40W, seperated in two adjustable channels. Must be enough to blow out my home's windows.

Now I will clean it inside at first. After that I will give it to my brother, who is a brilliant tube technician, by the way, for some check up.

Attached now a few pictures. These are not taken from my amp itself, but totally equal. Even the serials are close together!

Has somebody here an experience with what I want to go for?
I just found somebody in the net who wrote that these amps can sing really much. The input is adjustable, what means it has got everything for a very good old school distortion.

Enjoy the insight in good, old handwired quality from a time it was the only option to build amps...

[johnallg]

Looks like the parts are all top quality for the day. Very nice old amp!

[jps]

I love the icons; Orange has nothing on this amp.

EF86 input stages, EL34 outputs, this amp should sound great.

[paologregorio]

If it's been sitting that long you're prolly lucky nothing blew when you turned it on; the capacitors discharge over time when an amp isn't used, IIRC, and need to be charged up slowly with a variac before the amp's used. Killer amp, congrats!

[Hotzenplotz]

This one is making me crazy! Can't wait to hear it. I hope, I will not to be disappointed.

Yesterday I had the time to clean the inner working very carefully. 54 years old dust, combined with some nicotine from me, has its own special smell...
Fortunately it was not very sticky.
Now since last night it is looking inside exactly like the one at the pictures, too.

All parts are in a very good shape, as far as I could see. But, as Paul mentioned, I will boot up it very carefully (thank You for this advice!). Fortunately my brother can check all necessary things before. I am a very lucky guy at this point, having a godlike brother in tube techniques. He has had a three years professional education (and years of following experience) in this from the beginning of the 80's. Tube technology was still very common at that time. (And at the beginning 90's he stored a lot of - now NOS - tubes the people started to throw away...!) Today he just has to go down to the cellar (others do it with wine bottles), grabbing a few tubes and earning a few nice extra bucks.

I remember him as a 14 years old guy fixing old radios (before doing this as a professional). I was the little brother, staring at the glowing tubes, I found most interesting. - This amp brings a piece of the old times back, nice!

Today he is working in airplane research, so only his sparse time is the actual problem for me.


Here is a list of the tubes in the amp:
2x EL 34 (US: 6CA7)
2x EF 86 (US: ? - it is, as I know, a pre amp tube)
3x ECC 83 (US: 12AX7)

Is this a two separated channel output amp?


Maybe, knowing this set up now, You can tell me a bit more about the effects, habits and possibilities when using this amp. My brother hates guitars ( ), caused in the lessons he had, so I avoid to ask him about things that are normally interesting for a guitar player like me.


Some history at the end: In the late 50's and beginning 60's every german institution with big rooms (theatres, universities, churches, small cinemas, and so on) started to be equipped with these or similar amps. Telefunken produced tons of these amps. Even today some of them are still in use, unbreakable, good old, famous Made in W. (!) Germany quality. Unfortunately this "Made in Germany" is a dying, nearly dead thing in electronics.

I will keep You informed, maybe added with some sound files later.

PS: I wonder, if this 100 Volts amplification is/ was common overseas, too?

[jps]

Your amp is a mono output amp, but has two separate inputs, each having it's own volume control.

AFAIK, 100V distribution was not common here, in the US it is 70V for a distribution system, generally overheard conference room, office building type of audio distribution.

[Hotzenplotz]

Ah, o.k., but similar idea behind that.

[Hotzenplotz]

Now some more pics.

They are made with my old mobile phone, sorry for lousy quality. But now they show MY amp and not the one from another guy, found in the web.

As You can see the hood has got some peeled off paint areas from using it over the decades. There is no rust, because the massive 1mm (!) body sheet is zinc-plated. I will not change this, because that is real vintage. The chassis itself is completely without dings and scratches.

At first I wanted to change the wiring to customize it for guitar use. Now I decided to leave it in its original condition. That means a change of the sound has to be done by using the pots - old school, too.
Not to change keeps the dear amp in a 100% original condition and preserves the possibility to use it as a PA for smaller gigs.

Enjoy.

[jps]

Nice condition, overall, Sascha.

[Hotzenplotz]

Yeah! Thank You! I am a quite happy, lucky guy in this case.

Now just waiting for the speakers!

Then I will run in it very carefully. - After it I want to blow my band mates through the 12 square meters small practice room, with 40 all tube Watts.

I think my ELA is really close to the new VOX 50 Watts night train, just a few pots less.

[fatcat]

How about posting a picture of the back of it showing the terminals?

[Hotzenplotz]

Good idea, here they are (mobile pics with flash, urgh!):



Already night time in Germany.


In front there are two original plugs for connecting with hardware.

[jps]

It looks like there is a tape/line input, also. I am not sure what some of those hieroglyphics represent, do you know what all the connections are for, Sascha?

[Hotzenplotz]

It looks like there is a tape/line input, also. I am not sure what some of those hieroglyphics represent, do you know what all the connections are for, Sascha?

These hieroglyphics are very old fashioned, indeed!


From left to right:

1. Exchangeable fuse (the little round black knob).

2. This is not wired inside - inside other 306 ELAs, too. Something like a stone age standby or a free plugging place for whatever.

3. 100V - this is the normal working voltage of the output(!). That means, You need speaker boxes with a converter (inside). Normal speakers would be destroyed in parts of a second. To touch stripped cables of the speakers before the converter is "painful", too.

4. 2V seems to be some inside working voltage. I only can imagine that this plug position offers the possibility for sending the pre-amped signal to another, bigger amp via the usual exits. Next week I will know exactly what this 2V thing is. I promise to report about what my brother said then.

5. The red screw is for grounding of a record player.

6. Line in for radio/ TV.

7. Line in for record player.

8. (the first of the three round ports) Line in for tape (what meant the big ones at that time, not cassettes, but connectable to "modern cassette tapes, too.)

9. Right exit, adjustable in front.

10. Left exit, adjustable in front.

For line in I will use one of the brown elongated slots, I think no. 6.. The two black plugs lying in front of the amp are for this. And they do not fit into the 100V or 2V slots, fortunately. (Clever made!)
No. 8 has got the same layout like no. 9. and 10., so I do not want to create a line in adapter for port 8 - to connect the guitar in error with these exits would give the name "toasters" a new, very literally meaning!


BTW: ELA means elektroakustische Anlage, translated: electro acoustic system.


Actually I wonder if the 100V transmission will influence the sound in any way.

[jps]

The speakers that connect to the 100v output should each have a transformer to step down the voltage to that suitable for the speaker, I believe. This is what you mean by a converter, correct?

I think that #9 and #10 are low level inputs, the symbol on those make me think of microphones; why would there be a left and right output (exit) when the amp is mono, plus, they would not have put outputs at that location? In this case you should have no problem plugging your toaster equipped guitar into one of those, actually you could plug into any of the inputs, the volume may just be too low from the line inputs.

If # 7 is a phonograph input there should be an equalization circuit like the RIAA type (more likely, a European equivalent) to flatten out the response of the pickup cartridge.