As a tube enthusiast I´m thrilled that EBS finally makes a complete tube amp. Tubes have been incorporated into several EBS designs, but only with preamp tubes for making the sound a bit more lively.
The Classic T90 does not offer many features. Four knobs, six tubes and two transformers is really all you need for a good sound. The rear panel however, has a few extras. More of that later on.
If you are concerned about the somewhat low output power of 90 watts I can assure you that the T90 puts out as much as any tube head around 100w. Compared to my old Sound City 120w the EBS is just as loud. The EBS is definitely louder than my old Ampeg V4 rated at 100w.
With the tone controls centered, I turn up the volume for a classic tube tone. A warm but focused tone with a lot of definition. EBS has not been tempted to make the sound too polished and scooped out.
There is a lot of presence in the lower mids yielding a thick and very articulate sound that easily cuts through.
Pushing the power amp hard brings out the best in the T90. When the power amp tubes start to distort it quickly becomes clear that this amp was made to rock. The growling tone from distorted power tubes is what you hear on many old albums by Cream, Black Sabbath or Grand Funk. Someone compared this to the sound of a tractor. A four-stroke lawnmower engine is another description. Some tube amps distort very quickly and abrupt. This makes it hard to control the distortion. EBS however, have really succeed in making an amp that can be controlled with your fingers. A light touch gives a clean and clear sound. Dig in a bit more and you can hear the slightly compressed sound of a tube power amp working hard with just a little bit of distortion.
This makes the sound a lot more lively. Play really heavy and you get an in-your-face distorted tone. In my book this is what tube amps of around a hundred watts are all about. When you find the sweet spot where you can control the distortion like this, the sound level is right for most bands when using a decent sized speaker cabinet. The EBS 8x10" cabinet was great for this purpose. To get a three hundred watt tube amp to behave like this would make it too loud for smaller venues or at least too much for guitarists getting too much competition.
The EBS Classic T90 usually starts to distort somewhere between 11 o ´clock and 1 o´clock on the volume knob. Heavy distortion is not a problem as there is a lot more gain available. This compresses the sound a lot so the output level does not increase very much. There is still a lot of definition and string sound, so there is no risk of getting a muddy sound. If you should need even more distortion you can always a boost pedal of some kind.
This is a perfect amp for studio use. There is enough power to drive large cabinets, but you can still be in the same room when you play the T90 at full volume.
The front panel layout is simple. There are input jacks for passive and active basses. The knobs are volume, bass, treble and presence.
I think EBS did the right thing omitting a master volume. Using a master volume could add the possibility of preamp overdrive for another type of distortion, but most of the bassists that are interested in this type of amp will probably be after power amp distortion anyway.
The bass and treble controls are easily controlled with center detents and a very even sweep. They are effective but not overly dramatic. Full treble boost still sounds good without being too harsh. Although you might want to be a bit careful if you have a very sharp treble horn. Any tone setting sounds good. Using the maximum setting on the bass and treble controls sounds very full and muscular. An in-your-face tone that is sharp and cutting. Great for slapping or pick style playing. Slapping in particular sounds clear, cutting and very lively. I really don’t miss a midrange knob.
Reducing bass and treble is just as effective as boosting a mid control. This kind of increased midrange control boosts the upper mids, but thankfully it does not make harsh lower treble frequencies too dominant. With no bass and the treble knob at nine o´clock you get a growling midrange voice that is great for finger style playing when you need to really cut through a busy band.
The presence control takes some getting used to. After a quick listen you cannot hear much difference when you turn the knob. This filter is in the power amp and does not do much unless you reach power amp distortion. When the power amp starts to sound dirty the presence comes alive. Crushing pick-style sounds can get very brutal with full presence. Unfortunately the line-out is unaffected by the presence control.
Low end response is not a problem. Using the Classic 8x10" cabinet I had to turn down the bass knob to nine o´clock to get a balanced sound. I could get usable sounds even with full treble and no bass. Even if the woolliest bottom disappears the sound is not too thin.
There are some clever functions on the rear panel. Two speakon jacks, for speaker loads of 8 or 4 ohms respectively. For recording or PA there is a tube-driven balanced line out using an XLR connector. The most clever connection is definitely the one you need very rarely, namely a multimeter connection for power tube bias adjustments. Small screwdriver adjustment holes mean that you no longer have to open the amp for tube replacement or adjustments. Unscrewing the rear grill is all you need to reach the power tubes that are safely seated in chassis mount sockets.
EBS have put a lot of energy into trying different constructions, tube types and many different transformers. The production itself is in Hong Kong, in order to make the amp affordable. Not a lot of people would be willing to pay for a tube head made entirely in Sweden.
While doing this review the obvious question arise: When will EBS release the big brother of the T90? Many bassists are used to around 300 watts of tube power for a loud and clean sound even in larger venues. We are eagerly waiting for additions in the EBS tube amp family.
EBS ClassicLine 810
The EBS Classic T90 is a traditional tube amp with a focused sound.
EBS Classic T90
EBS ClassicLine 810