This turned up on the TV a couple of days ago:

One's already on its way here. As the video progresses and we get to the real 303 meat...and, oh my god...they DID IT!

See, the problem with replicating the TB-303 is two fold:

1) The filter doesn't have enough "grit". And...

2) The "glide" isn't easy to do...because Roland probably did that function "wrong" in the first place. But I was amazed when this did that "not really linear" portamento that's key to the 303 sound...and that's something that NO ONE has gotten right throughout the history of 303 clones!

...until now. And they even added a little bit of craziness by putting a headphone-out jack right next to the aux input. Minimoog feedback trick, anyone?

Just to make sure of this, though, I'll be putting this on a scope when it gets here so that I can look at the glide activity and a few other things. But when the demo switched for a bit to that wonderfully-hollow squarewave sound...wow. Just...wow.

Looks like Uli's got some competition over in China!


OK...it arrived this morning. I got it unpacked around 10:30 AM.

Then when I checked my watch again after fiddling with the B1 and putting it through its paces...it was 12:30 PM.

It's the real deal, sound-wise...even with a 4-pole LPF, as it sounds curiously 3-pole-ish...like the real thing. The glide function has Roland's odd little "error" of not being a fully linear portamento. Run up the overdrive circuit and oh...my....

Suffice to say, the sound is far closer to what I'm used to out of a TB-303 than anything I've encountered in the 30 or so years that companies have been trying to clone the original. It can be nice and pure...or hostile and gritty AF! And yes...everything in between (for a change!).

As for the sequencer...it's also like the Roland's (ie: obtuse as hell), but some of this comes from the way the sequencer gets accessed, which is technically better than the TB-303...but it's definitely got a learning curve. But it can do things such as syncing to a number of different clocks...including, yes, the 24 ppqn DINsync...and even Korg's 48 ppqn! Oh...and MIDI out.

Also, there's a way around the sequencer's normal edit and enter modes: Donner came up with some basic software editing that can handle that, plus a few other surprises. Just connect the B1 via its USB-C port to your PC, done. But if you insist on using only the B1's UI, you'll find that the gimmicky-looking keypads are also a much better set of control indicators than the teensy LEDs of Roland's box. They're bright and super-obvious.

So...how does this fit in with modular? Well, the sequencer is easily connected to most anything via MIDI, so you can use the B1 as a 1-channel MIDI sequencer. And also, it's got that audio input, which lets you impose the VCF's sequenced filter behavior on an external signal. I 100% cannot stress the importance of that MIDI I/O; it's THE reason why you might want one to couple up with a monophonic Eurorack build as both a controller AND monophonic sequencer.

Better than Uli's? Yes. The internal feature set is better (thanks to the sequencer's capabilities), the form factor makes more sense these days, and the fact that it can be used as a PROPER synthesizer instead of being purely a sequencer box. And there's that SOUND again...seriously, the VCF can do that hollow "snarly" sound and the VCF controls (key to performing with a TB-303) are super-responsive and also react very well to the gate length, glide, etc. So you can use the MIDI out to sequence, then fire the output off to the B1's audio input and use your whole damn modular system as the "voice"! Woo-hoo!!!!!

But the biggest deal of all is this:

Cheapest original TB-303 on Reverb: $3395
Donner B1 that sounds and acts pretty much identical to the TB-303: $160.

Oh, and one other point...if you've been over to The Website Formerly Known As Gearslutz and checked the threads on this, you'll notice that there's one of Donner's reps there as well, and they want input on how to make this thing even better through another non-TB-303 function: firmware updates. They're actually interacting and as opposed to a certain other China-based MI firm, they're not making lofty vaporware proclamations and showing off speculative renders but actually communicating so that they can make this box do things WE like via other actual users' input. What's not to like?

Lastly, the box lists some useful info for those of you in the EU and UK...distributor contact info. So for those wanting to know when this is available over there, here's the contacts:
UK: [email protected]
EU (Germany): [email protected]

I might sound a bit overhyped here about this, TBH...but this really is a big gamechanger, both in terms of being the best 303-alike ever, and in terms of moving the TB-303's design forward, rather than slavishly copying the original version. It's really that good!


Hi Lugia,

Ha, ha, sounds like you are having lots of fun with your Donner B1 :-) From what I can see and read from your experience report, is that this is seriously interesting!

Well... at the other side of the ocean we will wait "patiently" till it becomes available here at the regular dealers, let's see. I can't wait to have it tested at my local dealer :-)

Thanks a lot for the interesting news, have fun with your B1 and kind regards, Garfield.

For review reports of Eurorack modules, please refer to https://garfieldmodular.net/ for PDF formatted downloads


Fun? No, it's beyond that...the B1 is the first 303 clone (or in this case, 303 "reimagining") that I've heard across the 25+ years of 303 clone attempts that really behaves like the TB-303. And there has been a metric fuckton of those attempts over that timespan...with none of them nailing the REAL issues, those being the ones with the glide function and with how it deals with accents and ties. So, having watched all of that flailing from everyone from tiny boutique firms to big, huge multinationals, it's been both a shocker AND laff-riot to see Donner, with their very first synth offering, NAIL IT! No, it doesn't look like a TB-303 (actually, it makes more sense when in use!) but it sure as hell sounds like one.

Reminds me: I need to bug them about the possibility of adding a "kill" function to the VCO. At present, audio inputs get mixed along with the VCO, and if you wanted to use the B1 as a sequenced filter, that would be a problem. But since a lot of what's going on inside can be altered via firmware dumps (and Donner really wants to know what users would like to add to the firmware, when possible), it might be possible to have that function added.


All right, all right! I have added the Donner B1 on my wish list :-)

For review reports of Eurorack modules, please refer to https://garfieldmodular.net/ for PDF formatted downloads