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heatpipe? (was: Re: warm-up time CS80)

2007-11-07 by JH.

I once heard about someone who put a heatpipe into his CS-80.
I can imagine that will be quite an undertaking, mechanically.
But then you could force all the oscillators to be on a more or less fixed
temperature, couldn't you?

JH.

----- Original Message -----

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From: "erikfromhere" <moogsynthex@...>
To: <yamahacs80@yahoogroups.com>
Sent: Wednesday, November 07, 2007 9:39 PM
Subject: [yamahacs80] Re: warm-up time CS80

Maybe without the heat of the PSU, the voiceboards are more instable
because there will be more temperature-fluctionation within the CS80
(it will follow the roomtemperature which will differ from summer till
winter unless you've a conditioned room)? The PSU pre-heats the
interior making it more stable. Just a guess.
Anyway, my CS80's are fine once warmed up, I only need to tune them
once a year or so. Not worth the effort.

--- In yamahacs80@yahoogroups.com, rj krohn <r_j_d_2.phila@...> wrote:
>
> this still brings me back to that nagging question.....if the
instability is due to temp change, and the temp change is caused by the
PSU(right?), then wouldnt having the PSU on the outside of the chassis
solve alot of this problem? sorry, still just thinking out loud on
that....
>

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Re: [yamahacs80] heatpipe?

2007-11-07 by Magnus Danielson

From: "JH." <jhaible@...>
Subject: [yamahacs80] heatpipe? (was: Re: warm-up time CS80)
Date: Wed, 7 Nov 2007 21:58:29 +0100
Message-ID: <003201c82180$f4f3ad80$0400a8c0@jhsilent>

Jürgen,

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> I once heard about someone who put a heatpipe into his CS-80.
> I can imagine that will be quite an undertaking, mechanically.
> But then you could force all the oscillators to be on a more or less fixed
> temperature, couldn't you?

No, more or less the same temperature, not a fixed temperature.

You could of course consider heat sources in the cabinet.

I happend to know of a GX-1/CS-80 PSU project on the boiling-plate. It will be
muke warm at worst. Maybe that would be a better option?

Cheers,
Magnus

Re: [yamahacs80] heatpipe?

2007-11-07 by JH.

> Jürgen,

Nice to hear from you Magnus. It's been a while ...

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>> I once heard about someone who put a heatpipe into his CS-80.
>> I can imagine that will be quite an undertaking, mechanically.
>> But then you could force all the oscillators to be on a more or less
>> fixed
>> temperature, couldn't you?
>
>No, more or less the same temperature, not a fixed temperature.

The idea is a heatpipe with 17 contact points:
16 for the VCOs, and 1 with a *regulated* temperature (a heater or a peltier
cooler with thermostat).

JH.

Re: [yamahacs80] heatpipe?

2007-11-07 by Magnus Danielson

From: "JH." <jhaible@...>
Subject: Re: [yamahacs80] heatpipe?
Date: Thu, 8 Nov 2007 00:07:11 +0100
Message-ID: <117901c82192$ef856de0$0400a8c0@jhsilent>

Dear Jürgen,

> Nice to hear from you Magnus. It's been a while ...

Um Yes, I realize that. Been busy. Moving my studio to a separate shop among
other things.

Also doing unspeakable things like almost fooling people that I am the boss.
Not to worry, not at work!

Show quoted textHide quoted text

> >> I once heard about someone who put a heatpipe into his CS-80.
> >> I can imagine that will be quite an undertaking, mechanically.
> >> But then you could force all the oscillators to be on a more or less
> >> fixed
> >> temperature, couldn't you?
> >
> >No, more or less the same temperature, not a fixed temperature.
>
> The idea is a heatpipe with 17 contact points:
> 16 for the VCOs, and 1 with a *regulated* temperature (a heater or a peltier
> cooler with thermostat).

That was certainly not clear from what I had to go on (see text above).

Question is weither you need to go that drastic. Normal polyphonics certainly
don't need that. It is a bit of a heavy project.

You could do it much leaner and meaner if you attempt to approach it similar to
what we have seen in OB-8, Xpander or for that matter other modern analog
poly-designs.

That would mean a combination of temperature compensation and auto-tune.
Neither would require the rocket science and level of intrusion that the heat
pipe exercise would require.

In the old days you had a wooping Z80 and a 8253 doing the magic. These days
you have the necessary stuff sitting in a cheap of the shelf ARM. I doubt that
a very large range of tuning values actually is needed, but if so a better DAC
with associated S/H can be arranged for.

As with the OB-8 you can ignore hitting the autotune button. Sometimes you
would even like to have a detune mode where the autotune was canceled.

Or am I being too much of an advanced Synth-DIY man now?

Cheers,
Magnus