New Oberheim SEM is this SCD ?

[David Bulog]

Hi will it possible to service the new SEM  or will it be main board  
replacement only --I have been told it is surface mount rather then  
through hole
I cannot think of one synth tech that does repairs to SCD boards these  
days
interesting post
Sound difference between SMD and through hole
http://www.gearslutz.com/board/geekslutz-forum/432821-sound-difference-between-smd-through-hole.html

[Mark Pulver]

To David's specific question... Yes, the new SEM uses SMD.

Past that, we've had this discussion a couple of times now in recent months
and it generally ended up with minimal input from _engineers_ versus people
that thought they heard something different from an SMD versus through-hole
circuit. Not to say that golden ears need to be engineers, but there's a
certain amount of Monster Cable that has to be taken into account.

Running through this discussion again (third time's a charm?) could be
worthwhile from a knowledge point if new points are brought up, but I doubt
that any of us wouldn't buy a new SEM just because it uses SMD.

I'd suggest that reviewing the discussion on Gearslutz is probably
sufficient for those that want to know about the _technical_ side of the
issues.


Mark - kinda' deputying, but go for it.

-----
David Bulog (10:22 AM 11/3/2009) wrote:
 >Hi will it possible to service the new SEM  or will it be main board
 >replacement only --I have been told it is surface mount rather then
 >through hole.
 >
 >I cannot think of one synth tech that does repairs to SCD boards these
 >days.
 >
 >interesting post
 >Sound difference between SMD and through hole
 >http://bit.ly/3X5u2p

[Ancient Eyeball Recipe]

Last ditch attempt to find one of these at a good price....

[David Bulog]

Mark
The main point is i would think twice about buying it now because it  
uses SMD -the long term service aspects are the biggie and whether you  
can find a synth tech willing to work on a SMD board
What are you going to do when SEM is out of warrently a few years down  
the track--replace the main board at $599 while its still a stock item?

On 4/11/2009, at 8:01 AM, Mark Pulver wrote:

>
> To David's specific question... Yes, the new SEM uses SMD.
>
> Past that, we've had this discussion a couple of times now in recent  
> months and it generally ended up with minimal input from _engineers_  
> versus people that thought they heard something different from an  
> SMD versus through-hole circuit. Not to say that golden ears need to  
> be engineers, but there's a certain amount of Monster Cable that has  
> to be taken into account.
>
> Running through this discussion again (third time's a charm?) could  
> be worthwhile from a knowledge point if new points are brought up,  
> but I doubt that any of us wouldn't buy a new SEM just because it  
> uses SMD.
>
> I'd suggest that reviewing the discussion on Gearslutz is probably  
> sufficient for those that want to know about the _technical_ side of  
> the issues.
>
>
> Mark - kinda' deputying, but go for it.
>
> -----
> David Bulog (10:22 AM 11/3/2009) wrote:
> >Hi will it possible to service the new SEM  or will it be main board
> >replacement only --I have been told it is surface mount rather then
> >through hole.
> >
> >I cannot think of one synth tech that does repairs to SCD boards  
> these
> >days.
> >
> >interesting post
> >Sound difference between SMD and through hole
> >http://bit.ly/3X5u2p
>

[Mark Pulver]

Hmmm... Are you concerned about long term reliability or "my roadie plugged
a live AC line into a CV input?".

Long term wise, I think SMD has through-hole beat. You're right though,
live AC into a CV input is an issue. :)

-----
David Bulog (03:24 PM 11/3/2009) wrote:
 >Mark
 >The main point is i would think twice about buying it now because it
 >uses SMD -the long term service aspects are the biggie and whether you
 >can find a synth tech willing to work on a SMD board
 >What are you going to do when SEM is out of warrently a few years down
 >the track--replace the main board at $599 while its still a stock item?
 >
 >On 4/11/2009, at 8:01 AM, Mark Pulver wrote:
 >
 >> To David's specific question... Yes, the new SEM uses SMD.
 >>
 >> Past that, we've had this discussion a couple of times now in recent
 >> months and it generally ended up with minimal input from _engineers_
 >> versus people that thought they heard something different from an
 >> SMD versus through-hole circuit. Not to say that golden ears need to
 >> be engineers, but there's a certain amount of Monster Cable that has
 >> to be taken into account.
 >>
 >> Running through this discussion again (third time's a charm?) could
 >> be worthwhile from a knowledge point if new points are brought up,
 >> but I doubt that any of us wouldn't buy a new SEM just because it
 >> uses SMD.
 >>
 >> I'd suggest that reviewing the discussion on Gearslutz is probably
 >> sufficient for those that want to know about the _technical_ side of
 >> the issues.
 >>
 >>
 >> Mark - kinda' deputying, but go for it.
 >>
 >> -----
 >> David Bulog (10:22 AM 11/3/2009) wrote:
 >> >Hi will it possible to service the new SEM  or will it be main board
 >> >replacement only --I have been told it is surface mount rather then
 >> >through hole.
 >> >
 >> >I cannot think of one synth tech that does repairs to SCD boards
 >> these
 >> >days.
 >> >
 >> >interesting post
 >> >Sound difference between SMD and through hole
 >> >http://bit.ly/3X5u2p

[Oakley Sound-2]

All electronics has a limited lifetime be it SMD or through hole. Parts
go obsolete, SMD ones as well as through hole.

The JP-8 is full of through hole parts. Many of the ICs are now
obsolete. I've been working on a SH-7 recently. Could I find some
replacement switches for the front panel? No I could not. I had to
cludge it with some new smaller footprint ones.

If a tech can't handle working on a board with the larger SMD 0805
resistors then honestly he should practice a bit more. There should be
no issue at all in servicing a board like this even with basic soldering
equipment. Roland, Yamaha and all the others have been using SMD in
their synths and effects since 1986.

I certainly have no problem with SMD servicing so long as its not the
really small stuff - eg. computer motherboards etc. That stuff you do
need more specialised equipment.

Tony

www.oakleysound.com

[David Bulog]

Try and tell that to Roland NZ service agents --they will replace SMD  
boards rather than repair --its just not cost effective
On 4/11/2009, at 8:37 PM, Oakley Sound wrote:

> All electronics has a limited lifetime be it SMD or through hole.  
> Parts go obsolete, SMD ones as well as through hole.
>
> The JP-8 is full of through hole parts. Many of the ICs are now  
> obsolete. I've been working on a SH-7 recently. Could I find some  
> replacement switches for the front panel? No I could not. I had to  
> cludge it with some new smaller footprint ones.
>
> If a tech can't handle working on a board with the larger SMD 0805  
> resistors then honestly he should practice a bit more. There should  
> be no issue at all in servicing a board like this even with basic  
> soldering equipment. Roland, Yamaha and all the others have been  
> using SMD in their synths and effects since 1986.
>
> I certainly have no problem with SMD servicing so long as its not  
> the really small stuff - eg. computer motherboards etc. That stuff  
> you do need more specialised equipment.
>
> Tony
>
> www.oakleysound.com

[Oakley Sound-2]

 > they will replace SMD boards rather than repair...

There are two reasons for this:

1. Most new SMD boards have complex digital electronics on them. The
most common failures will be within the large specialised digital chips
(ICs). The bulk of the electronics is contained within those ICs. Its
harder to fault find at the device level and the boards are actually
relatively cheap.

I will openly admit I would probably board swap on something like a
Kurzweil K2500 - I wouldn't have a clue on how to fault find that one
down at component level.

2. Many official service centres will generally board swap on current
models as a matter of policy. The broken boards will then be sent back
for rework and repair at the factory. This also allows for the factory
engineers (if they have the time) to assess what sort of faults are
happening in the field.

Looking at that SEM board, I really don't think any technician would
find it hard to fix. It's really relatively simple stuff and laid out
very nicely.

Tony

www.oakleysound.com

[Florian Anwander-2]

Hi David

> Try and tell that to Roland NZ service agents --they will replace SMD
> boards rather than repair --its just not cost effective
That has nothing to do with SMD. Ensoniq never had any other type of
repair service - even in 1985 where everything was through hole. If you
look at the service manual of an ESQ1 you will find only a description
to analyse which board has to be changed at what kind of failure. It is
simply a question of how fast a synth can be repaired (vulgo a question
of customer satisfaction).
And btw unsoldering and resoldering a SMD is much simpler and faster
than a through hole device (but I have to admit, that my eys have
difficulties to focus SMD transistors. I'll need reading glasses
someday, but what do I ask after having such a nice 50th birthday party
recently...)

Florian