Hi folks!
Recently I was given a old pair of two EL34 amps, where the manufacture and the origin was “unknown”..
So I’ve searched the net for a while and tried with “Image search” to find some info, but without luck.
So now I trying with you guys! And hopefully someone here recognize them:
Each amp has:
x1 GZ34
x2 EL34
x1 ECC83.
Best regards!
Recently I was given a old pair of two EL34 amps, where the manufacture and the origin was “unknown”..
So I’ve searched the net for a while and tried with “Image search” to find some info, but without luck.
So now I trying with you guys! And hopefully someone here recognize them:
Each amp has:
x1 GZ34
x2 EL34
x1 ECC83.
Best regards!
Those are swedish build DIY amps.
No company has build them, someone bought the parts and assembled them in private work.
Thats not only possible today, it was always. Have some private pics of the same steel enclosures which someone in private work has used to build his own DIY amps. Its not rocket science to do it that way.
No company has build them, someone bought the parts and assembled them in private work.
Thats not only possible today, it was always. Have some private pics of the same steel enclosures which someone in private work has used to build his own DIY amps. Its not rocket science to do it that way.
I agree with the DIY assessment. Notice the screw, as opposed to rivet, mounted sockets. The magnetics look substantial. IMO, there's every reason to believe a nice pair of monoblocks could be constructed reusing the magnetics, chassis, and some of the hardware (including sockets).
The OP is overlooking the Noval (9 pin mini) socket on the front panel. I think it will be needed.
GZ34/5AR4 B+ rectification is very tried and true. Add the provided series SS diode tweak to make the use of low cost Sovtek 5AR4s reliable. CLC (Π section) filter the B+, recycling the choke currently in situ.
Mullard style signal topology is "idiot resistant" and, therefore, a safe choice. The provided EICO 87 schematic shows quite suitable Mullard style signal circuitry. Substitute a Noval 6CG7/6FQ7 for the Octal 6SN7. The types are electrically equivalent. Wire 1 amp to use only section 1 of a 12AX7/ECC83 and the 2nd amp to use only section 2. When signs of wear appear in the voltage amplifier triodes, flip/flop the tubes between amps and enjoy doubled service life.
If the O/P "iron" lacks ultra-linear taps, SS regulate O/P tube g2 B+ at some fraction of anode B+. That sort of full pentode setup is quite competitive with UL mode "finals".
The OP is overlooking the Noval (9 pin mini) socket on the front panel. I think it will be needed.
GZ34/5AR4 B+ rectification is very tried and true. Add the provided series SS diode tweak to make the use of low cost Sovtek 5AR4s reliable. CLC (Π section) filter the B+, recycling the choke currently in situ.
Mullard style signal topology is "idiot resistant" and, therefore, a safe choice. The provided EICO 87 schematic shows quite suitable Mullard style signal circuitry. Substitute a Noval 6CG7/6FQ7 for the Octal 6SN7. The types are electrically equivalent. Wire 1 amp to use only section 1 of a 12AX7/ECC83 and the 2nd amp to use only section 2. When signs of wear appear in the voltage amplifier triodes, flip/flop the tubes between amps and enjoy doubled service life.
If the O/P "iron" lacks ultra-linear taps, SS regulate O/P tube g2 B+ at some fraction of anode B+. That sort of full pentode setup is quite competitive with UL mode "finals".
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Thanks for your input guys! Very interesting reading I must say 🙂
After a while of googling, I slowly realized that this must be the case.. Since not a single one appeared with only the main transformer mounted in the middle on its top, or with the same type of chassis.
Anyway. I'll probably keep the transformers, if they still work (Long time in damp storage..), and some socket or two.
Best regards
//Embuza
After a while of googling, I slowly realized that this must be the case.. Since not a single one appeared with only the main transformer mounted in the middle on its top, or with the same type of chassis.
Anyway. I'll probably keep the transformers, if they still work (Long time in damp storage..), and some socket or two.
Best regards
//Embuza
are these possibly organ amplifiers? so many things about the layout and constuction of these smacks of "output amp" from an organ right down to the the twist cinch jones style connector on the right to the location of what one assumes is the volume control....but i'm often wrong...
Hi turk 182! And thanks for your input 🙂
Unfortunately, I never received any further description/information about these two amps.. But maybe you're right!
Best regards!
//Embuza
Unfortunately, I never received any further description/information about these two amps.. But maybe you're right!
Best regards!
//Embuza
That printed label on the power transformer makes me think they are commercial amps. Looks like there would have been two GZ34’s originally, so some serious power.
All the transformers and chokes has the same “ES” / “E-S” sticker on them (Which I guess is the manufacturers logo..?), followed by an “A”, and a five digit number.
About the GZ34(s), the second hole in the chassis for the second GZ34 are plugged, on both amplifiers. But from the sticker over the fuses tells, just as you say, that there should be two GZ34 on each amp.
That is not diy and I agree with OldHector there were some manufacturers in Sweden who did good stuff at first I thought it was Danish products but not. My tip is that you post the pictures on hififorum.nu so it is probably someone who recognizes them.
Hi guys! And thanks for your tips 🙂
Interesting! I will! 🙂
Best regards
//Embuza
I have missed to come in 40+ years of audio life to see ONE commercial amp that has no label, no hints of which company produced those. Makes no sense for me to do so.
So I would still say, this is all DIY gear.
If you look closely, you will see that these two amplifiers have been in something else and I guess an early PA equipment or an audio console that I am sure is the flange that is where my hottest tip is that these have been in a movie theater .
Then that I know that no Swedish OPT was made for private persons in Sweden, it was only companies that could order, it was probably not until Lundahl that made it possible otherwise you had to order from abroad.
Then diy did not really start until Dynakit became available in Sweden then it became more common. People were poor and did not earn much money then listening to music as a hobby was very unusual maybe one or two academics but not among ordinary people in the old days.
Then that I know that no Swedish OPT was made for private persons in Sweden, it was only companies that could order, it was probably not until Lundahl that made it possible otherwise you had to order from abroad.
Then diy did not really start until Dynakit became available in Sweden then it became more common. People were poor and did not earn much money then listening to music as a hobby was very unusual maybe one or two academics but not among ordinary people in the old days.
Lundahl doesn't do customs for private persons, thats what distinguishes his company from several other transformer manufacturers.
As a company, Lundahl will be able to cooperates and build customs if your willing to buy some dozens.
A private person can order Lundahl transformers from one of their distributors and after ordering, Lundahl will satisfy that order by manufacturing those transformers. I know because I just ordered a pair of transformers, and they were made just in time after ordering. The same procedure is known by many companies, even in Sweden. It has nothing to do with private orders, its a distributor ordering system.
I'm sorry I do not talk about customs OPT from Lundahl but I just mentioned that you can buy as a private person it is you who twists the reasoning. Buying from Lundahl is nothing to brag about, I have bought a lot of my OPT from LL so it is nothing special. Then I think this discussion is over.
I didn't brag about buying from Lundahl, because I haven't done this.
I bought from a distributor for his products, and thats the normal way to do it.
Just proved your statement as being wrong, that there were no companies prior to Lundahl to sell their products in sweden by distributors to private persons. An odd statement at all that simply says that you may not be old enough to know how this was handled some 50 years ago.
Maybe you know distributor catalogues in paper format, that was the way every company sold their products to private customers.
And you think that didn't happen in sweden???? LOL
You must be very lazy or late to know how business was being handled prior to internet.
There wasn't any discussion about that, its a fact. A long time ago when you hit the road.
P. S. I bought from Lundahl directly when they hit the internet, early 1990s. Even that time, you may have missed. Lundahl was an early adopter of the direct internet marketing.
I bought from a distributor for his products, and thats the normal way to do it.
Just proved your statement as being wrong, that there were no companies prior to Lundahl to sell their products in sweden by distributors to private persons. An odd statement at all that simply says that you may not be old enough to know how this was handled some 50 years ago.
Maybe you know distributor catalogues in paper format, that was the way every company sold their products to private customers.
And you think that didn't happen in sweden???? LOL
You must be very lazy or late to know how business was being handled prior to internet.
There wasn't any discussion about that, its a fact. A long time ago when you hit the road.
P. S. I bought from Lundahl directly when they hit the internet, early 1990s. Even that time, you may have missed. Lundahl was an early adopter of the direct internet marketing.
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Is it off topic when writing that the builder was able to source the components and build this gear as DIY and another person denied this?
Do you know how facts are being handled to have arguments for one or the other source for this amps origin?
I don't think so.
Your post should be removed, because it says abolutely nothing new to the subject of the thread. Pure nonsense.
Why not making a substantial fact statement instead of posting bollocks?
Do you know how facts are being handled to have arguments for one or the other source for this amps origin?
I don't think so.
Your post should be removed, because it says abolutely nothing new to the subject of the thread. Pure nonsense.
Why not making a substantial fact statement instead of posting bollocks?
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