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OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.

OK , I have been recently in possession of two OB-6s, one a replacement for the other. One was a SEQUENTIAL serial #03638 and the other was a DSI serial number #03632. How close is that?

Perhaps there will be some mixing of numbers as the old cases get used up but the DSI/SEQ boundary might be right there. This is with units shipped to the UK. Maybe we have some of the very first Sequential OB-6s.

Sadly my SEQ OB6 had that awful clanging on the sub-oscillator discussed elsewhere on SYNC patches, often, with the 2 on / 4 off pattern showing up. The new one, which is a DSI :-( actually seems to work better. If it doesn't I will let you know. It's strange that there are these differences between the instruments like that. Maybe slightly different sources or grades of components get used or there are some tweaks to the circuit design along the way?

I was sad when I opened the box and the second one was a DSI not a SEQUENTIAL but it seem to work better than the one only 4 serial numbers later. How curious. I lost faith in that first machine and the refund/replace window was still open, so it had to go.

I felt so down when the second one arrived and the whole ownership of the thing seemed spoiled. Not so with my Prophet-6 that never showed a hint of a problem in 18 months and seems a more robust unit IMHO. I just kept making music on it day after day and loved playing the thing, so fulfilling and a non-professional just writing/improvising your own music on such a great little synth - and it is quite little, small enough to sit very neatly on top of the upright piano next to a photo of my late Dad.

Now with the second OB6, after feeling so downcast earlier in the day, I actually seemed to be able to make some music on it a couple of hours ago. I hope this one beds in better.
« Last Edit: July 26, 2019, 01:14:00 PM by DaveP6guy »
Prophet-6 nut. Formerly, just a Prophet-5 nut.

It's strange that there are these differences between the instruments like that. Maybe slightly different sources or grades of components get used or there are some tweaks to the circuit design along the way?

I think you're probably reading into it too much. Sometimes there are lemons, plain and simple. You mentioned mathematics in another thread, so I'm sure you're aware that statistic analysis revealing a trend line is not possible in a singular case. If more Sequential branded OB-6s popped up with the same issues, then that's worth postulating. As you also know there was a case with "exactly" the same sub issue from 2016 , which does at least seem to conflict with your theory.
« Last Edit: July 26, 2019, 03:59:04 PM by Ocean Machine »

Kja

Are you saying you had a ob6 that had sequential badging instead of DSi? Do you have pictures?

*Pic courtesy of DaveP6Guy.

Kja

Wow that's neat, I guess now all the songs from them are labeled sequential now.. does that mean new tempest's are labeled sequential? And does that mean the price of the old Dave Smith ones will go down if everybody wants a sequential one? It the opposite? Maybe they will be a collector item...

Wow that's neat, I guess now all the songs from them are labeled sequential now.. does that mean new tempest's are labeled sequential? And does that mean the price of the old Dave Smith ones will go down if everybody wants a sequential one? It the opposite? Maybe they will be a collector item...

Thanks for the acknowledgment. I had put the above photo that I took of my new OB6 on the Facebook OB6 forum a fortnight ago. Also someone has a SEQUENTIAL labelled REV 2 machine photographed and of course the limited edition last white Prophet-12s have it on the front under the keys on the left in the same way as the Prophet-6 does. That's on the company's website.

I have now seen an OB-6 only six serial numbers earlier than mine that still have Dave Smith Instruments on it. SO that's a nice little curiosity. I have another photo.
Prophet-6 nut. Formerly, just a Prophet-5 nut.

OK , I have been recently in possession of two OB-6s, one a replacement for the other. One was a SEQUENTIAL serial #03638 and the other was a DSI serial number #03632. How close is that?

Here's a photo of both of them.
Prophet-6 nut. Formerly, just a Prophet-5 nut.

Have you checked that the firmware version is identical in the synths that you have compared?
DSI OB-6, Nord Electro 3HP & 6HP, Roland SoundCanvas SC55mkii, Beatstep Pro, Minibrute 2S, MPD18 (+mpcstuff), Roland TD-4 V-drums, Fender-Rhodes Stage MK1, Reaper, plus dozens of acoustic instruments and mikes.

Have you checked that the firmware version is identical in the synths that you have compared?
Yes it is and it's the latest one as of July 2019. As for the weird sub-oscillator thing, Carson at Sequential is helping me with this. it may be a characteristic of the architecture of the Osc 1 ,Osc 2 Subosc combination in SYNC mode and the particular waveforms generated that the subosc is having to follow. It's just that it does it better on unit #03632 than it does on unit #03638.
https://www.youtube.com/playlist?list=PLkDrBr6YDpo4gm1e52_64RVL1KH2putgB
Prophet-6 nut. Formerly, just a Prophet-5 nut.

Have you checked that the firmware version is identical in the synths that you have compared?
Both read 1.5.5 on power on.
Prophet-6 nut. Formerly, just a Prophet-5 nut.

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #10 on: August 08, 2019, 10:28:49 AM »
Concerning differences between units, Carson had told me at one time that my unit OB6 Module serial 00566 had slightly different hardware inside than the later ones, which created a small problem with the LEDs (some brighter than others) on the panel on latest firmware revisions, which was not present on earlier firmware revisions.

DSI had worked with me in trying different private beta version firmware to try and correct the issue, but to no avail. I've elected to revert to OS 1.2.0 (the original one that came with my unit) because, for my needs, it works better than the latest one and I prefer to have my control panel LEDs all the same brightness...

BTW, I don't have the OP problems with the oscillators clanging. My unit works perfectly, and I love it ! Of course, mine is identified as Dave Smith Instruments on the back and not Sequential.
« Last Edit: August 08, 2019, 10:31:42 AM by AlainHubert »
Minimoog D (vintage), OB6 (Desktop), Oberheim Matrix-6 (MIDI Controller), Prophet REV2-16, DeepMind 12

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #11 on: August 16, 2019, 10:54:25 AM »
My Sequential-logo unit is serial # 03778 and has the sub-osc versus sync thing. As discussed elsewhere, the sub-vs-sync is inherent to how sub-oscs and hard sync are implemented in analog -- I don't consider it a bug, just a combination of features that isn't very useful. If you drop VCO2 by an octave, turn VCO1 a little more towards square, and fiddle with the cutoff and resonance you should be able to get the equivalent of synced sub-oscillator, anyway.

I guess they could conceivably make the sub track VCO2 instead of VCO1 when sync was on, or make the sync reset the sub, but I imagine that either of those would require a hardware change.

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #12 on: August 18, 2019, 11:21:43 PM »
I just got an OB-6 new.  It's got Dave Smith on the back and serial number 01523.  That seems like a low number for a new one.  Are the Sequential logo versions older?

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #13 on: August 18, 2019, 11:31:02 PM »
Are the Sequential logo versions older?

No, the opposite.

I just got an OB-6 new.  It's got Dave Smith on the back and serial number 01523.  That seems like a low number for a new one.

Must've been sitting around for a while unsold.

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #14 on: August 18, 2019, 11:48:13 PM »
Thanks.  I guess I shouldn't worry about it.  It is new, it came in a factory sealed box, and everything is working fine.  It had OS 1.0.0 loaded in it, I updated to the newest OS and that went smoothly.  Are there any known hardware issues with the older Dave Smith OB-6s?

kyps

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #15 on: August 19, 2019, 10:56:13 AM »
 :o

Hi there,

there is a message from Sequential service.

I asked if that was normal than my new ob6 module was an "DSI" product, so the reply was :

"Hi Kevin-

Congratulations on your OB6 module purchase. The OB6 module does have DSI and not Sequential on the silk screen. The unit was produced around May of this year."

My unit was produced on May 2019... DSI 01614...

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #16 on: September 05, 2019, 08:32:16 AM »
OK , I have been recently in possession of two OB-6s, one a replacement for the other. One was a SEQUENTIAL serial #03638 and the other was a DSI serial number #03632. How close is that?

Here's a photo of both of them.
Just out of curiosity, does the later serial number OB-6 with Sequential printing on the rear have the same printing on the front edge below the keys as the earlier Dave Smith labeled unit ? Or did they just change the Dave Smith logo on the rear to Sequential ?
DSI OB6, DSI Pro 2, DSI Prophet 12, Elektron Analog Keys, Elektron Digitone, Moog MemoryMoog Plus, Yamaha DX7IIFD Grey Matter E, Strymon BigSky, Strymon Timeline.

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #17 on: October 05, 2019, 10:03:05 PM »
OK , I have been recently in possession of two OB-6s, one a replacement for the other. One was a SEQUENTIAL serial #03638 and the other was a DSI serial number #03632. How close is that?

Here's a photo of both of them.
Just out of curiosity, does the later serial number OB-6 with Sequential printing on the rear have the same printing on the front edge below the keys as the earlier Dave Smith labeled unit ? Or did they just change the Dave Smith logo on the rear to Sequential ?

Everything is the same except the rear logo change. The beautiful "Tom Oberheim" signature is still there front right. No added 'sequential' on the front left or anything either.

I'm a big fan of the sequential name and logo, moreso than the DSI logo, on the newer Rev 2s (my ex rev 2 was one of the first) and the Prophet 6 it really suits it.

However, as an owner of an OB-6 in the 03Xxx (3000's) range with the DSI logo on the back, I honestly believe on the OB-6, this synth of all, works BETTER having both Tom's and Dave's signature logos on. Probably the only time you'll hear me say that (as the sequential logo is just better in general on all his other synths).

OB-6 was a joint one-off product wonder synth between 2 legends so it makes sense both of their signatures are on there, not just because of having two real names but because it (to me) looks better with the Tom's signature thing, in keeping, while the sequential logo looks a bit stuck on and out of context with the emphasis on Tom's signature front and back.

At the end of the day though it really doesn't matter one bit, and anyone worried about their OB-6 having the older logo shouldn't, it's the "original and classic" look with the 2 legendary sigs, anyone with the newer logo also.. don't worry.. nobody cares once you start playing that bad-boy and the gorgeous sonics hit you (and as players we don't really see the rear that much anyway).

I wouldn't go assuming there were any hardware changes between DSI/Sequential badges units either, it would put weird rumors out there. Yes EARLY <1000 serial? or so OB-6s did have slightly different hardware (glitchy sometimes as confirmed above) but any 3000 series or higher, regardless of a painted logo on the back, is going to be pretty much the exact same synth with exact same quality. One bad unit of either badging doesn't mean anything about the rest of them!

Re: OB-6 Serial number curiosity. Dave Smith Instuments vs Sequential OB-6s.
« Reply #18 on: October 07, 2019, 11:55:39 AM »
Thanks Synthead.
I originally owned an OB-6 keys serial number below 0246, obviously with Dave Smith logo on the rear. I sold the synth and immediately had huge regrets. I now just received my new OB-6 to replace it, itís serial number 3916, which has the Sequential logo. Iíd prefer the Dave Smith logo like the original as I agree itís such an awesome one off collaboration between Dave and Tom and with Toms signature, I fee itís only right to have Daveís on it too. Like you say, makes zero difference otherwise, itís still the same fantastic sounding and hugely inspiring synth that Iím extremely pleased to have back in my possession. Iíll just forget the logo and continue to enjoy it as it should be !
DSI OB6, DSI Pro 2, DSI Prophet 12, Elektron Analog Keys, Elektron Digitone, Moog MemoryMoog Plus, Yamaha DX7IIFD Grey Matter E, Strymon BigSky, Strymon Timeline.