x0xb0x - Best TB-303 Replica (xoxbox analog synth)

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"The x0xb0x is an analog replica of the legendary Roland TB-303 synthesizer. It uses the same components, in the same schematic, to match its sound — perfectly. The difference in sound between a well-made x0xb0x and a TB-303 is about the same as the difference between one TB-303 and another.

AcidVoice has judged it as having the best sound out of the nine TB-303 clones it tested.

'An original TB-303 was disassembled and reverse-engineered to verify the schematic. The original transistors were analysed using big expensive curve-tracers to determine their characteristics. We measured every waveform and counted every cycle.'
— x0xb0x creators

The x0xb0x copies not only all of the electrical interconnections inside a TB-303, but incorporates the old, rare analog components, such as 2SC2291 matched-pair transistors and AN6562 op-amps. Consequently, it has earned the reputation of having the most faithful sound of all 303 clones. In addition, the x0xb0x supports MIDI, has a non-volatile EEPROM (no backup battery), and can save and restore patterns to a computer.

The x0xb0x is usually available as a kit, with customers placed on a year-long waiting list to receive the official version. The kit is very affordable, but the difficulty of putting it together is not small, for an electronics hobbyist. A musician may find the task daunting. The difficulty lies not so much in placing the components, or of using a soldering iron, but rather in fixing problems in the x0xb0x that are discovered only once the whole thing is built. Often, it is something random, such a transistor that was killed by static electricity, or mixing up one of the five hundred components. If this happens, finding the fault is difficult without an oscilloscope and a reference, though the generous members of the adafruit forums try to troubleshoot problems. Perhaps as many as half of self-built x0xb0xes don't work right away (and some of these wind up on Ebay).

For those who have more interest in creating music rather than electronics, buying an assembled x0xb0x makes sense. The x0xb0xes we sell are assembled with experience. Moreover, they are tested thoroughly. The analog section is carefully compared to a reference machine in A/B listening tests, to guard even against flaws that change the character of the sound only subtly — flaws which may slip unnoticed without reference testing. Finally, the x0xb0xes are tuned using a high-end oscilloscope. The tuning is aided by high-precision trimpots that are ten-fold more precise than the ones bundled in the official kit.

This x0xb0x is made using old, original transistors for an unmatched sound, and brand new buttons and potentiometers for a long life. Constructed by x0x Source, it comes with a 1 year warranty. The aesthetic design is customized, featuring a beautiful front panel that feels rich to the touch. Also bundled are printed forms of the manual and a CD with the documentation, software for upgrading firmware, and complete source code and schematics. The x0xb0x, after all, is an open source product.

The reasons that we think make x0x Source the biggest and most trusted supplier of fully assembled, tested, and warrantied x0xb0xes are:

* Experience and quality -- We've already assembled and shipped dozens of x0xen. We use computer-aided testing and calibration, together with careful A/B listening tests to guarantee each x0x.
* Solid return policy and warranty -- Full refund within 30 days. Comprehensive warranty on parts, labor, and two-way shipping for one year.
* Honesty and communication -- All questions answered in one day. If there is ever a problem or delay, we bite the bullet and tell the truth.
* Fast delivery -- Next-day shipping via EMS. Delivery to most European countries takes one week (including customs).
* Reputation -- We really can't say much more than our customers. Their cumulative rating of our x0xes (known as "Item as described") is 5.0 out of 5.0."