Echolette amplifiers

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Echolette was a brand owned by Hans Bauer intended for selling stuff made by Klemt. Untill 1959 Klemt was mainly focused on radio stuff. They jumped into the instrument amplification by that year.

The first and main products were the great NG51 tape echo and its associated amplifier the M40. The M40 was kind of multipurpose PA system for bands, the idea was plugging on it the vocal mics, the electric instruments and adding some echo to it with the NG51 device. The M40 had four speaker outputs like a typical PA amp. Its 30 some watt output is not impressive but it was a powerful and highly refined system by that time. The M40 is powered by a EL84 quartet and has four identical and independent channels (typical of any mixer) plus a line input for the NG51. Besides being originally a power mixer, it's a great guitar amp for rich clean sounds. It sounds gorgeous. I has a tone control for each channel, but they are out of sight, they are conceived as tone presets and the four adjusting wheels had to be reached by removing the top cover of the unit. They are placed at the back of the volume pots. Quite strange system.

It's not difficult to get some grind from this amp if we prefer it this way. The power amp is ultra-linear so the easier way to get some some more bolder sound is rewiring the power transformer in the regular way. That is removing the screen resistors from the Ultra-linear taps of the output transformer and connecting them directly to the power supply. There is already a point in the high tension rail ready for this mod. So it's just rewiring two wires. Another way to get some more from the preamps, or just some of the preamps if we want to keep one or two pristine clean (there are four to choose!), is replacing any (or some) of the plate resistors for higher value ones. Something like a 100K to 220K Ohm instead of the stock 20K plate resistors. This will do the trick for an even more versatile amp.

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The M40 and its partner the NG51 tape echo.



This is the row of tone controls hidden inside the chassis (the four cream wheels).



We can see also the screening "wall" isolating the preamp from the power amp and the power supply for a noiseless operation. A welcome feature hardly seen in instrument amps. These are high quality very well built units. They are very abundant and constantly sold in ebay.de.

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Though the guys at Klemt never made a wide variety of instrument amplifiers unlike Dynacord, they got a bit infected, but mainly focusing in bass amps. By 1962 they introduced an amp based on the Fender 5F6A Bassman. It was the B40... It was a few years before Jim Marshall did the same with his world famous JTM45! It's seems that the Bassman fame spread all over the world very soon. Jennings (Vox) got inspired on it for the famous AC30 top boost mod, Sinmarc in Spain made their own version in the mid '60s (though they chose the blackface version)... The Fender Bassman certainly set a trend.

The B40 was basically a Bassman tweed circuit variation. The guys at Klemt wanted a clean sounding bass amp, so they chose to use a ultra-linear power stage. This arrangement keep the power amp cleaner which is good for bass or clean guitar sounds. Like in the M40 this arrangement can be easily modified into a regular power stage just rewiring the tube screens. Again there is a spot in the power rail ready for this mod. They have a master volume placed in the back of the amp. This kind of masters don't work so good in this kind of amps but it's useful if we want to play at low levels or when the sound guys come around yelling about turning down our amp at a club stage. All in all this amp is not too far from an early Marshall plexi Superbass amp after the non ultralinear mod, and only a few minor tweaks more can make it very close to a highly desired and costly JTM45... or an EL34 powered Bassman tweed.

There was a B40N version too. I don't know the details or the circuit of ths amp but I guess it's not too different from the original B40.

These two amps are scarce and very short lived. Only a year after they hit the market they were replaced by the common and abundant BS40 version. This amp keeps the original concept but with a few improvements and refinements above the original circuits. The former ultra-linear power amp was finally replaced for a regular power amp. The bias circuit was made adjustable in two ways and the adequate measuring resistors added for easy bias setup, this is the kind of circuit that any push pull tube amp should have, but only a few have it. It's usually only seen in costly boutique custom amps or highly critical amps like the Ampeg SVT. The rectifier tube was replaced by a diode bridge, a varistor added for power transformer surge protection, the master volume redesigned for a better working one, and perhaps the only drawbacks are that the choke was lost and replaced by a resistor, so a bit inferior noise filtering than before. and the second drawback is that the ECC83 tubes were replaced by ECC808. This tube is a rugged heavy duty ECC83 like developed by Telefunken for very low noise, very low distortion audio use. This doesn't sound like a drawback at first instance, but the truth is that this tube is highly sought after by audiophiles, so the prices of NOS tubes are going crazy. The big problem here is that the ECC83 has similar specs and would work perfectly well in ECC808 circuits and viceversa, but the tubes pinouts are different, so they are nor direct replacements. These amps have the tube sockets mounted on the printed circuit boards, so the pins cannot be rewired easily. Some guys sell socket adaptors to use ECC83 tubes into ECC808 sockets. They are cheap and good solution if we don't want to pay the high ECC808 prices or prefer the typical overdriven sound of the ECC83. So for clean sparkling sounds stay with the ECC808s onboard, if you want the Marshall/Bassman thing, better go for ECC83 tubes. Even an in-between combination of these two tubes is possible if we happen to like it mixed.

Any of these three B40 variants are a very good way to grab a kinda Bassman/JTM45 head at a very low cost and much better built that any of these two guitar amp icons. They are highly recommendable. I've been always tempted to buy some, but I always back off because I don't want to go beyond 30 watts again. 15 watters are my thing... anyway they always make me drool.

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The original B40



The scarce B40N



The typical BS40

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There were a few more good amps, but most of them are hybrids with transistor fronts. Those like the B25, B30, S40 Showstar and Bassmaster 100. These amps sound good and clean but use to have odd power tubes. So keep this is mind if ever tempted by any of these babies.

Perhaps the more interesting of the full tube amps is the M80. It's the M40 big brother powered by two EL503 tubes instead of an EL84 quartet giving 55 watts. The EL503 are costly tubes and it's not that easy to convert these amps for EL34 use. So the M40 is a much more recommendable buy. The M80 was replaced by the M120, though a good full tube amp, again powered by EL503 tubes.

About the hybrid amps, the S40 and Bassmaster 100 are two nice clean sounding amps using EL34 power tubes. If we want clean power, these two are good stuff. Also, if we are not using vibrato or don't bother about it too much, these two amps are a good base for a 100% tube amp project if we want to take that mess by using the vibrato tube replacing the transistor first gain stages. They are certainly weird amps. They have cheap transistor preamps and a costly tube vibrato. A hard to understand approach.

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There is one more amp that worths to be mentioned. In the Dynacord days before Klemt and Echolette parted ways and Bauer bought the 50% of the Dynacord, Echlolette launched their own Dynacord Twen version. It was the Echolette Junior, basically a Twen with a different box and look. They offered also a Junior reverb version not available from Dynacord.

[zutique]

I have an M40 and all I can say is that is an amazing amp. I´ve got mC5/stooges sounds with it goes crancked and fenderish clean tones at low channel volumes. The original tubes have to be replaced and I don´t know where to get the manual to bias the amp, anyone know it? are the bias of the m40 cathode or fix?

Thanks and best wishes for all the old german tube vintage amps

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Hi Zutique. It's fixed bias but lacks a trim pot. A good thing to say the truth. Many instrument/guitar amps die due to faulty/dirty bias pots. Though a very common trend, it's much safer having them biased by fixed resistors. Any "serious" high quality amp maker won't use bias pots.

I can send you an schematic scan if you give me your email address. You'll find it's a very very good conceived amp. A design much closer to the exigent Hi-Fi market specs and standards than the typical "get it fast and cheap" instrument amps.

Here goes an excerpt anyway. You'll have to mod the voltage divider (R85 and R90) to get the right current across the output tubes. I use to first check the right value with a provisional variable resistor and then replace it with fixed resistors of proper value.

[zutique]

Hi Snap,

Thank you very much for the super fast explanation!! my email is susogen@hotmail.com. I don´t have a lot o f experience with amps mods, I will talk with a tube radio technician friend of mine to do the work. Maybe also, I will order to change the caps that could be dry (I read your nice post of dynacord amplifiers). I also have a hohner orgaphon with ec808 preamp tubes, it´s also a nice amp with extra clear tones and a super spring reverb.

Thank you very much Snap, best regards from Spain

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Hohner Orgaphon are great clean amps having one of the best and juicier reverb circuits ever made. Some have weird hard to find tubes, but the ones with PL84 are a good choice.