About a year ago I acquired off EBay yet another of the many Geloso amplifiers that I own. This one came from a very nice gentleman called Antonello (or Anton for short), in Italy.
After receiving the amplifier from Anton, and as the transaction had been very smooth with quite a lot of communication between us, I chose to send some photos of my Geloso rebuilds for him to see. (This was before my web-site was up and running.)
Further to me sending them, I got a very pleasant e-mail by return, full of compliments on my work etc. He further went on to explain about all the amplifiers and Hi-Fi equipment that he owned himself, and that included a good few Geloso units, of which there were three identical G-226-A models.These were circa late 40’s / early 50’s. The tube line-up is (working from left to right) 2 x 12SL7’s, 1 x 6SN7, 2 x 6L6’s and 1 x 5U4 rectifier.
It wasn’t much longer before Anton asked me the 'Million Dollar Question'……."How much please for you to rebuild two of these for me, for use on my Hi-Fi?” As all of my previous rebuild/restoration Geloso tube amps, when offered for sale on EBay, had sold very well and for pretty good money, I already had a fair idea on what to quote Anton for the work to be undertaken.After a few more e-mails between us, we eventually struck a deal and the ball started rolling.
Part of this deal was for him to strip the best two of his 226’s and send them to me without all the items I wouldn’t need such as components, screws, tube bases, tag boards etc, as I would obviously be replacing these. He also had to pay all the shipping costs, both from Italy to the UK plus the return costs too, as part of the said deal.
Anton's two Geloso's with top covers removed; in the condition that I received them, although stripped.
Left: One of the amps with cover fitted, before stripping. Right: Chassis wiring prior to stripping.
He agreed to all of this and the stripped amplifiers duly arrived here around October 2005. Anton was not in a hurry and I estimated (with other repairs always in to do) that I could have them completed around May 2006. I made that deadline by having them finished at the end of May 2006!
An interesting point here is that I also owned a pair of G-226-A’s, and were on the list to be rebuilt at some point in time, like all the Geloso amplifiers I presently own. (About 33 to date I think?) This being the case, and although it would be hard work, it seemed sensible to restore all four of them in one go! This would also be cheaper, from the chassis cleaning and powder coating point of view, than just doing the two!
Once having made this decision, the two of mine were rapidly stripped down also! I now had all four stripped and ready for the mammoth project!
Covers and chassis for all four amps stripped down
Chassis & covers after chemical treatment. (The rust patches that can be seen are surface only and are remanent of the treatment - They wipe off easily.)
Firstly, the chassis have to be re-drilled in certain places for the new, modern tag boards. Also the front holes for the input sockets had to be made larger to take the XLRs.
The new XLRs installed (left) and re-drilling of a chassis (right).
Planning and building the new tag boards.
The completed tag boards.
Next all the chassis' and transformers' metalwork had to be taken in for de-greasing and the removal of all paint and rust etc.
The transformer covers before being sent for powder coating.
Transformer cover after powder coating ("Chrome"), and still showing transformer model number "6010".
The final part of all the metalwork issues is the powder coating. I let Anton choose the colour and he chose the “Hammerite Dark Grey” for all the chassis metalwork. I was happy to go along with this too. The metalwork from the transformers was also finished in powder coating and is a colour called “Chrome”. This looks so natural and great.
Cases and chassis back from the powder coating process.
As Anton wanted to use these amps as part of his Hi-Fi set-up, I recommended that I re-wind his two output transformers to make them more suitable for this purpose, to which he agreed.
The two re-wound output transformers.
The four original power transformers with new fly-leads, awaiting covers.
During the whole of this I have kept Anton constantly updated with e-mails and photos as the project progressed. The photos below really tell the whole story but what I will add is:
. (Also before……none.)
(1.) The main smoothing capacitor is 330uf. (Before, it was 32uf!)
(2.) The second smoothing capacitor (after the big resistors network) is also a 330uf. (Before 16uf!) The HT line is now flat-lined!!
(3.) The final two capacitors further down the HT line are both 47uf . (Before, they were 32uf and 16uf respectively).
(4.) All the bias and pre-amp tubes’ heaters supply are all 220uf. (Before they were about the same and do not need to be a higher value).
(5.) I have added about 10db of feedback, this improves performance somewhat, especially for Hi-Fi usage.
(6.) I have wired the rectifier sockets to take any of the 5U4, 5X4, U52 range/family of tubes.
(7.) I have fitted 2 x 20 turn pre-set potentiometers on the bias of the two 6L6 output tubes, giving very accurate setting of same……Before there was none! There are also 2 more of these potentiometers: one for total “drive balance”, and one for “overall gain”
(8.) All tube bases are glazed ceramic with gold plated pins.
(9.) All resistors are 1 watt (or higher) and are flame proof (were necessary).
(10.) There are two 1 ohm 1% resistors (one per tube) in the cathodes of the 6L6’s for the read off of 1ma/V set-up.
Other than some of the minor modifications and improvements above, the whole of the circuit remains the same, i.e.....original.
When I was getting close to finishing these two for Anton, I e-mailed him to send me his tubes. (It was also part of the deal that he supplied all the tubes). He has some lovely tubes, especially the brand new Mullard ECC32’s (which I have used instead of the 6SN7), and the beautiful Haltron 6L6’s. Good ‘Ole British tubes again!!
The final tests on both of them proved an identical, perfect 28.45 watts true RMS each. These amplifiers are normally rated at 25 watts, but they are certainly better in all ways now than when they were new!
Anton has now got both of these amplifiers back in his home in Italy. They have “pride of place” in his living room, and he loves showing them off to all his friends!He probably has the best pair of Geloso G-226-A’s in the whole of Italy!
Anton's two Gelosos back home in Italy.
I hope you all found this interesting.
Cheers for looking, John.
PS: A few months after I had carried out the above work, I received the following very nice email from Anton:
"....My Dear John, I have always thought that having gotten to known you via your web-site, e-mail and then telephone has been a big luck and pleasure for me but, after the PERFECT work/restore on my two nice monophonic GELOSO G-226-A amplifiers, I'm very, VERY glad to be your FRIEND. First of all, I think I could not give in BETTER HANDS my old amps!! I was always following with big attention all your updating Mails on the restoration as it progressed, and I was often not believing to my eyes when I was seeing all the "old parts" going BACK to live and to SPARKLE!!! In a few words, your total work/restore is wonderful, perfect in any details, very clear and respectful, up where it was possible, of the original apparances!!
With just two things you've completely changed, naturally informing me before because you're an absolute serious person, they are "the choke" that was placed over the chassis instead inside and this has given a much better total look and the other was "the rewiring of the secondary of the output transformer", in this case for to reach a SUPERB quality of sound, MUCH BETTER then the original response!!! I also think that describing your "meticulous work" is absolutely useless, because everything is CLEAR and VISIBLE in all the photos published in your nice web-site!
Instead I would like to add a last thing about the final result of the sound quality; it's unbelievably WONDERFUL!! I'm a lover of vintage hi-end sound and in my life I have listened to many glorious tube amplifiers, so I know what I mean by real vintage warm tube sound.
The sound that comes out from the pair of Geloso G-226-A's restored by you through my splendid Tannoy loudspeakers, it's absolutely PERFECT, nothing to envy a many expensive and boasted tube amp of today!!!
THANK YOU VERY MUCH JOHN!...We've many other old device to restore, like my next original and rare TELEFUNKEN TRIODE amplifiers!...
Till the next time my dear Friend.".... Anton.