Loose knobs ?

Loose knobs ?
« on: December 23, 2016, 12:49:39 AM »
Hey guys.

I have been in love with DSI synths for a while and decided to get myself an xmas gift of a new P6!

I unwrapped it just recently and noticed at least 1/4 of the knobs are "loose". I saw some forum posts about "wonkiness", or rotation off-axis, but my issue is different. There is movement of about 1/8" or more when handling some knobs. They feel as though they are mounted to nothing and might snap if not grabbed softly. Mostly the knobs on the right side.

Anyone else have this issue? It sounds beautiful but I really don't want to worry about messing up the PCB someday because I grabbed the knob at an angle while playing.

Any options besides returning it? :(

I'm actually very bummed out. Half of the board's quality feels lower than a pawn store special plastic OD guitar pedal. But other areas it's solid.
« Last Edit: December 23, 2016, 12:53:34 AM by TacticalHamster »

Re: Loose knobs ?
« Reply #1 on: December 23, 2016, 06:23:40 AM »
Hey

What can I say, the knobs have a tiny bit of play which is I expect to be normal. On mine it is up to 1mm of play when wiggled (not something you should do too much with pots anyway). Over 1/8" play does sound quite excessive.
Are they really loose? The 'ratchet pots' i.e. Clock and FX knobs are a little looser (but still only 1mm play maximum)

If you feel that your Prophet is not up to scratch then I would definitely do a return (guaranteed unopened exchange). Not worth ruining your Christmas over it and for a 'real' instrument which is a serious investment you need to be happy with it.

All the best


Re: Loose knobs ?
« Reply #2 on: December 24, 2016, 05:39:20 PM »
Thanks for your reply synththeory.

I know talking about loose knobs/pots is subjective. I was hoping a few users would have popped in with a "me too" or "not me", to build an average from.

I'm including a short clip demonstrating what happens when grabbing the knob from different angles as if tweaking the setting. This applies to quite a few of the pots (1/4 - 1/3 maybe). I also notice that some of the LEDs are dim and appear almost off, and the pitch wheel sometimes drops registration of the up movement. Calibrating it fixes it for a while though.

Here is the youtube vid: https://youtu.be/JqvGhxxRKJE

I should have purchased it from a reputable place like Sweetwater. I bought it new on amazon, sold by a third party Unique Squared. Seems they have a 15% restocking fee even if item is completely broken, which is significant considering the 3k price tag.

First foray into DSI and really bummed.

Re: Loose knobs ?
« Reply #3 on: December 26, 2016, 04:09:40 AM »
I've not noticed any of these defects on my P6, which was new in March 2016. If I had I would have sent it back for a replacement, which I'm sure would not have been a problem given the quality of customer support from both Andertons (uk) and DSI.
Big synth stuff: https://www.youtube.com/channel/UCJkR38XLkFear5Sf9QypQvA
| Kurzweil Forte | Casio Privia PX 5s | Nord Electro 3 73 | Studiologic Sledge Black| Roland Juno Di | DSI Prophet 6 | Oberheim DPX 1 | EMU Esi 4000 | 2 x Yamaha Tx7 |

Re: Loose knobs ?
« Reply #4 on: January 02, 2017, 04:34:44 PM »
Your video shows about the same amount of wobble that's apparent on my P6 also. 

I was a little skeptical at first, like you, but I was assured this was within normal manufacturing parameters by DSI customer service and I haven't had any issues so far under normal use. 

I was hoping for three grand we'd get rock solid bullet proof knobs with absolutely no play, but it is what it is.  Some keyboards are stiffer than others it seems.

However, the LED readout should not be faint to the point where you can't see what value you're working with.  I'd be wary if it's not consistently lighted all the time. 

Also, you shouldn't be calibrating your pitch wheel that often. 
« Last Edit: January 02, 2017, 04:39:40 PM by jmananquil »
Moog Voyager, Prophet 6, OB-6 Desktop, Korg MicroKorg-S, Toraiz SP-16 and AS-1.

Re: Loose knobs ?
« Reply #5 on: January 02, 2017, 04:40:37 PM »
Your video shows about the same amount of wobble that's apparent on my P6 also. 

I was a little skeptical at first, like you, but I was assured this is within normal manufacturing parameters by DSI customer service and I haven't had any issues so far under normal use. 

I was hoping for three grand we'd get rock solid bullet proof knobs with absolutely no play, but it is what it is. 

I think you're good to go.

Possibly. I did have other issues that I didn't post here (but are uploaded to YouTube also):
- pitch up not working (even after calibrating) mid-session randomly
- some LEDs dimmer than the rest
- some voices not firing when hit (no pattern to reproduce)

I returned that unit. DSI was helpful after contacting, but I do not agree it's within parameters for 3k. I think it's within their acceptable tolerances, but it wouldn't be with other manufacturers.

The replacement unit (from sweetwater) is 109 digits up from the original serial and has zero issues. Not a single knob has lateral movement, LEDs are uniform, pitch wheel works, and voices always fire. This new unit is a well-built (heirloom quality) unit that feels worthy of the 3k price tag.
« Last Edit: January 02, 2017, 04:50:34 PM by TacticalHamster »

Re: Loose knobs ?
« Reply #6 on: January 02, 2017, 04:50:02 PM »
Thanks, TH!  I'll take a closer look.  That wobble on all the knobs has always bugged me from day one.  Too late for me to do the 30-day Sweetwater defective exchange.  But if DSI thinks this is normal they will probably not be willing to replace it with an entirely new keyboard.  My only option at this point would be to sell it off and buy a new one with hopes that it's an heirloom quality keyboard.
Moog Voyager, Prophet 6, OB-6 Desktop, Korg MicroKorg-S, Toraiz SP-16 and AS-1.

Re: Loose knobs ?
« Reply #7 on: January 02, 2017, 04:57:18 PM »
Thanks, TH!  I'll take a closer look.  That wobble on all the knobs has always bugged me from day one.  Too late for me to do the 30-day Sweetwater defective exchange.  But if DSI thinks this is normal they will probably not be willing to replace it with an entirely new keyboard.  My only option at this point would be to sell it off and buy a new one with hopes that it's an heirloom quality keyboard.

When you wrote that you experienced the same, that was a worry of mine too: sounded like you've had it a while. DSI may have a large margin of acceptable tolerance, but, as a consumer, you should be happy. I'd consider seeing what sweetwater can do. They offer their own 2yr warranty and work directly with DSI.

If I recall correctly, the pots are mounted to 1 or 2 PCBs under the lid. When you open the unit, they are mounted to the top. Ribbon cables link up those boards with the main board at the bottom, which also holds the voice "cards". They look like old school AGP video cards (snap in/out).

The reason I bring this up, is that I know a few prophet (6, '08, etc) users that have worked with sweetwater in getting these components to replace (under their own warranty. The system is very easy to maintain and it's not at all messy inside.
« Last Edit: January 02, 2017, 05:07:04 PM by TacticalHamster »

Re: Loose knobs ?
« Reply #8 on: January 02, 2017, 05:05:51 PM »
Here's a video. Not finding many videos for repair is a good sign!

https://youtu.be/Q0_B6jREjCo

Re: Loose knobs ?
« Reply #9 on: January 10, 2017, 02:51:49 PM »
So I spoke too soon about replacement being perfect and opened a thread for that issue. Sigh.

Re: Loose knobs ?
« Reply #10 on: February 02, 2017, 11:27:45 PM »
So this is just an expected DSI quality these days. On my fourth replacement (for other, non-knob issues) and still had wobbly knobs that feel like it'll last a year at most.

Embarrassing for an American-made product that costs so much. The OB6 was solid throughout...but also came with an old OS, so it's likely laziness over time with their quality/testing on the P6.

Re: Loose knobs ?
« Reply #11 on: February 03, 2017, 04:18:38 AM »
I received my Prophet 6 on January 20. A lot of them are 'wobbly', some more/less than others.
It turns out, the pot is not wobbly in relation to its attachment to the PCB, its the shaft in the base of the pot itself.
You can see this by removing the plastic knob and gently rocking the shaft. You will see (and sometimes hear the lubricant) rock back-and-forth. The potentiometer is attached firmly to the PCB but some of the shafts have a bit of 'wobble'. They are 100% functional however. I've never seen this before, so I cannot say with certainty that this does not affect its long-term reliability.

I did email DSI support and was told earlier this week:
"There will be some tolerance with the movement of the pots. They should all be 100% functional, however."


Re: Loose knobs ?
« Reply #12 on: February 03, 2017, 10:32:40 AM »
I received my Prophet 6 on January 20. A lot of them are 'wobbly', some more/less than others.
It turns out, the pot is not wobbly in relation to its attachment to the PCB, its the shaft in the base of the pot itself.
You can see this by removing the plastic knob and gently rocking the shaft. You will see (and sometimes hear the lubricant) rock back-and-forth. The potentiometer is attached firmly to the PCB but some of the shafts have a bit of 'wobble'. They are 100% functional however. I've never seen this before, so I cannot say with certainty that this does not affect its long-term reliability.

I did email DSI support and was told earlier this week:
"There will be some tolerance with the movement of the pots. They should all be 100% functional, however."

^^ this exactly. I have a support ticket open now. Here is an audible and visual sample of it:
https://youtu.be/v2QupNOJvUI

You will hear the grease and see the wide lateral movement allowed. These are some seriously bad pots. I do not have faith with this synth being around long-term without issue.

I build custom guitar pedals (amongst other things), and have ordered the cheapest of cheap pots in bulk and the more expensive/tolerant ones. I've maybe have had a couple of these every few hundred (about 2:300).

One member privately messaged me that DSI offered to send him the pots to solder, or have soldered, in as replacement. He wasn't satisfied with quality, understandably, and returned it and moved on to something else. While my time is limited, like most here, I'd be willing to solder in some tightly-spec'd pots (sourced from DSI or other).

Re: Loose knobs ?
« Reply #13 on: March 06, 2017, 08:05:18 PM »
So, I just bought a brand new, unboxed, Prophet 6 yesterday at Guitar Center. Upon setting up my new synth I was happy to experience the sturdiness or the solidness of the knobs, however. Once going through all the main components on the main board (OSC, Effects, Mixers, etc etc) I couldn't help but notice a trend. That discovery was the "looseness" or the "wobbliness" of the knobs. Some knobs worse than others. However, the Oscillator 1 "Frequency" knob appears to be the worst. This knob has the most looseness, wonkiness, wobbliness, and feels subpar to other premium keyboards I own. IMHO, there are some that have a wonkiness to the eye when spinning the knob, and there are some knobs that have very minimal looseness, but there are some that are just beyond the boundaries of what some have described from a DSI perspective as being "within tolerable limitations."

I will be CERTAINLY returning this unit since it is only my second day as an owner. I've barely even touched the synth to even add any kind of wear on the knobs. I cannot foresee these knobs holding up for a very long time with prolonged use with normal wear-and-tear. Certainly not with excessive use.

Here is a video I made demonstrating the inconsistency of the synth between the knobs: https://youtu.be/gG1KQ-zCGVk

Wonkiness I can get over, but when there appears to be mechanical defects, then electronics definitely don't last long. If this is, however, an engineering design, then I think DSI should release information as to why these proposed defects are in place from an engineering perspective. However, I would like to see them take one of these units, put it under specific testing conditions consisting of prolonged use exceeding normal wear-and-tear and see if these knobs hold up. I'm quite sure they have CAD engineers that can simulate these scenarios. I BET that these knobs do not hold up over a long period of time. Some of them, yes. But the one's that have significant "looseness"? Definitely not.

Thoughts anyone? Oh, I specifically joined to express this same exact issue. My Serial Number is in the 4,200's.

Here is a video I made demonstrating the inconsistency of the synth between the knobs: https://youtu.be/gG1KQ-zCGVk
Prophet 10 Rev4
Prophet 6
Pro 3
Rev 2 16voice
Moog Matriarch Dark
Access Virus TI2
Korg Kronos 2 88
Akai MPC X

Re: Loose knobs ?
« Reply #14 on: March 07, 2017, 09:54:48 AM »
Out of curiosity, is this a problem on the desktop module as well, or only the keys?  I'm plotting out my next DSI purchase, and because of desk space I'm only really looking for modules at this point.  Would hate to have wobbly knobs if that's my main touch interface with a piece.

Re: Loose knobs ?
« Reply #15 on: March 08, 2017, 07:57:54 PM »
Out of curiosity, is this a problem on the desktop module as well, or only the keys?  I'm plotting out my next DSI purchase, and because of desk space I'm only really looking for modules at this point.  Would hate to have wobbly knobs if that's my main touch interface with a piece.

This affects both.

It seems the earlier serials didn't have this issue. After returning 3 or 4 P6 units (not just because of wobble, but other bad QA issues), I got one that works, but still with lateral wobble. I love the sound of the P6, and will just live with it. Honestly, I've decided what you get with this poly overshadows imperfections like this.

I did find out that the lateral movement of the pots are just the shafts inside the pots, not PCB flexing or something that would require repair. DSI did send me some pots just in case, but one day, when I'm free (never), I'll tap each pot to check their resistances and replace them with higher quality ones.

The OB6 has a bit of wobble in some pots, but its practically a battleship of rugged construction (thicker top coat, knobs that are flush). I just wish the P6 had that same attention to detail.

Re: Loose knobs ?
« Reply #16 on: March 09, 2017, 12:03:14 AM »
FYI the powdercoat and the pots are the same spec on both instruments, and have been since serial #1 for each. Not sure how you got that many units in a row you were unhappy with, but that's pretty much unheard of as we have great QA and attention to detail for all our instruments. I'm sorry that was your experience.
SEQUENTIAL | OBERHEIM

Re: Loose knobs ?
« Reply #17 on: March 09, 2017, 12:10:40 AM »
FYI the powdercoat and the pots are the same spec on both instruments, and have been since serial #1 for each. Not sure how you got that many units in a row you were unhappy with, but that's pretty much unheard of as we have great QA and attention to detail for all our instruments. I'm sorry that was your experience.

Maybe the OB6's larger knobs give the perception of greater tactile feel (and doesn't allow such great bends when turning the knobs).

I am unsure of how I got that many units either. I was told by a highly reputable music retailer that they'd had quite a few DSI poly returns due to various issues more recently, though. They didn't specify the OB6/P6 designation or model, but didn't bat an eye when I had so many in a row with issues (one with a failed keybed on half of the black keys, distorted output audio and unit lock-up on another, etc). These were all new-in-box, same OS, etc. Thankfully, they agreed to pull a unit out and test it for 24 hours and then ship it.

Yeah, i have some wobble with current model. Yeah, sometimes the keybed fails to register on certain keys, too. It's the least troublesome of the lot and I'm sticking with it. I love the sounds, and that's important. I build custom guitar pedals/amps, so I have myself as support if needed down the road. If I was an average user, I'd definitely be more hesitant and look at another poly.

Re: Loose knobs ?
« Reply #18 on: March 09, 2017, 12:20:47 AM »
Again, I'm shocked at your experience. We have a less than 1% failure rate across the board. However, mechanical and electrical parts do occasionally fail or don't meet spec. Fortunately, we do have a great warranty policy, and, our out of warranty policy is the best in the business hands down which is $25 per repair. Rest assured if you have any issues down the road we will take care of you.
SEQUENTIAL | OBERHEIM

Re: Loose knobs ?
« Reply #19 on: March 09, 2017, 12:25:02 AM »
Again, I'm shocked at your experience. We have a less than 1% failure rate across the board. However, mechanical and electrical parts do occasionally fail or don't meet spec. Fortunately, we do have a great warranty policy, and, our out of warranty policy is the best in the business hands down which is $25 per repair. Rest assured if you have any issues down the road we will take care of you.

True. For anyone reading, i'm not bad mouthing products by DSI by any means. I love their synths, and they have some equally-minded music support staff. I had some so-so people on support, but some excellent as well. This is a smaller company, and will actually LISTEN (look at the rev2 re-branded as Prophet Rev2) and respond back to you (unlike Korg and others).

I had a bad run, but maybe that truck had a driver that liked hitting speed bumps (the serials are only a few digits off). Who knows. I am happy with what I have. There are things I wish were better quality-wise, i.e. more stable pots. I get the extra cost involved with tolerances, but that's something I can do on my end.
« Last Edit: March 09, 2017, 12:27:11 AM by TacticalHamster »