Let’s say it quickly : the blofeld is not really a V.A. (Virtual Analog) synthesizer in the way that it does not seem to possess algorithms to generate the randomness which is the main analog synthesizer characteristic. On the other hand, it’s an excellent digital synthesizer which combines two different synthesis (even three with the possibility of « FM »): sampled waveforms reading (classical primitive waveforms and those of the « Q » and » Q « ) and the wave tables (especially those inherited from the microwave II, XT, XTk series).
The blofeld has three oscillators with many parameters which can then be mixed and sent to two independent filters. For each oscillator one can choose the level of transmission to filter 1 and filter 2. The routing possibilities are quite large, as are the number of filters (6 modes, including the traditional HPF, LPF 12/24dB, but also the notch, comb + / comb- and a mode « PPG » which is of type 24dB and emulates with some success the filter of the famous PPG). The filters are really effective and sound really good! Also in this very comprehensive section there is the possibility of varying the saturation of the filter in order to simulate at best certain behaviors typical of certain synthesis or of certain analog filter technologies.
It will be noted that there are possibilities of routings between the filters allowing to create an extremely sophisticated harmonic variations …
The synthesis engine also allows us to use up to four envelopes. The first is for the DCA, the 2nd for the DCF, the remaining two will be assignable to the modulation matrix. Three LFOs are also available, featuring waveforms like the classic sine, triangle, square, sawtooth, S / H (sample & hold) and random. These LFOs have different modes of synchronization (Midi, key on, triggers, …) and can even become « FM » sources in their own right.
Although this small module does not offer many buttons (only 7 rotary buttons), the menus are extremely well designed. One can really say that the programming interface is a small wonder. The screen even displays graphics related to waveforms, envelopes or the routing of oscillators connected to filters.
However, there are libraries editors (mac / pc) that will also help to make the necessary adjustments in a much more comfortable way.
Then, we’ve an effect section for connecting two effects modules. There are the modulations (chorus / flanger / phaser) and temporal (delays / reverbs). The delays are convincing, but the reverbs are very cold and metallic … which can also be an advantage depending on what we want to produce. The chorus is really pretty average, but the phaser and the flanger are really good. Speaking about the phaser, it’s necessary to pay attention during the settings of the phaser not to explode the eardrums if one hears the sounds with the headphones to volume rather high, because the results of this phaser can become extreme for the ear. To me, this is pretty much the only reproach that could be made to this synth.
I will not really cover the possibility of the built-in arpeggiator which apparently looks extremely well designed and powerful. Unfortunately I can not talk about it because I have never been interested in anything that constitutes a kind of internal sequencer related to a synth. I prefer (by far) to use a computer-related program if I need to use a sequencer.
I managed (with a lot of work) to recreate some analog sounds very close to those that could be created on a real analog synthesizer. We’ve to master a lot of parameters at the level of the modulation matrix (pitch micro variations, or opening filters, …). The three LFOs will make it possible to give themselves to heart joy. The main problem comes, in my opinion, from the oscillators that generate extremely rough, aggressive sawtooth/pulse with a very marked digital character. It is therefore necessary to include some slight variations of pitch, intensity, slight effects of vibratos, and cyclic nuances in the opening of the filters to create an illusion of analog sound.
But we can clearly see, through the 1000 presets delivered with the machine, that the Blofeld is, above all, a synthesizer designed to produce metallic sounds, digital, or having a complex harmonic content.
I found that this synth generates a pretty noisy output. This is surprising because I expected to have a near total absence of this kind of parasites, like on Novation Ultranova, or other modern V.A. synthesizers. Strange … Then, using the USB port instead of a conventional MIDI connector also generates a noise (continuous dull purring). I tested with two different midi interfaces and 3 different computers. Same results :(
Fortunately I use the USB only to program the Blofeld using a computer-related sounds editor … But it seems incredible to ignore such a electronic design issue.
Aside from these flaws, I am really impressed by the hardware architecture of this machine which needs only 4 chips :
- A microprocessor (Freescale MC9S12UF32PBE 16bits / 30Mhz): CPU + usb management
- A DSP (Freescale DSP56371 24bit / 180mhz)
- A rom+ram memory circuit (Samsung K9F1208UOB 64m x 8 bit nand Flash) which is responsible to store sounds, arpeggios, … but also the memory containing the waveforms, and including the operating system. A « all-in-one » circuit.
- A Digital-to-Analog converter (AKM438)
I couldn’t entirely disassemble my synth because it seems Waldorf has made some major hardware updates and now the circuits are located underneath the LCD … and because this display is soldered to the mainboard, it’s no longer possible to have a easy view on those circuits. So I used 2 photos found on the net to illustrate what these famous circuits look like.
This machine that offers such a condensed of impressive possibilities therefore needs only one single DSP to generate the overall rendering of 16 potentially different stamps on a maximum polyphony of 25 notes … It must be believed that at Waldorf one knows how to program in a very optimized way. It’s really impressive. For example, the Ultranova has only 18 notes of polyphony (theorically) for a single sound … while the motherboard contains many more electronic circuits, DSP, …
In summary, I would say that this synthesizer generates a clearly « digital » sound signature but that nevertheless can get close to analog sounds in a credible way ! The synthesis engine is extremely complete and, in my opinion, the creative possibilities are really limitless … The interface is very well designed also. In addition, this module is multitimbral up to 16 parts, which is really impressive. The polyphony announced is 25 notes, but this may vary according to the complexity of certain sounds as well as the number of effects used, the complexity of these, etc. This polyphony can therefore get down significantly, but it remains quite acceptable.
The only defects that I know him are: a section of effects not so well designed, a sound quality pretty noisy, and finally a noise phenomenon purring when using the USB.