MOTM

The Triple Preamp has :

a) 2ea 1/4" unbalanced line level inputs to 10V pk-pk MOTM level outputs (with gain pot and
bi-color LED indicator). But me being me, has all DC path, OPA177FP DC-servos, Class-A outputs,
blah blah blah. You were expecting TL072s??!?

b) 1ea guitar input with gain pot (no LED, what the heck to guitar players care about
clipping??!?)

1U module, with 3 pots, 2 LEDs and 6 1/4" jacks all on a small pc board.


The Input #1 has:

a) 1ea pretty decent (ie "better than your Mackie") mic preamp with phantom power, LoZ-HiZ
switch. Balanced in, MOTM-level out (at full gain).

b) 1 REALLY good RAIA preamp for those big flat black things that hold music (so I'm told). RCA
inputs, 1/4" outputs.

c) 1 REALLY good headphone amp (99.99% of headphone amps that you have heard are using cheesy
JRC4560 op amps for 14 cents).

Input #2 is for +4dBu balanced input from "somewhere" to 1/4" unbalanced outputs, unity gain. 1U,
2 or 3 on a panel with mults/clipping LEDs. Duplicate rear connectors for "back patching" into
patch bays.

The Envelope Follower is a dedicated module that assumes MOTM-level inputs (and generates
MOTM-level outputs). Still in design and parts-pondering. Not your boring full-wave rectifier
stuff, neither :)

Paul S.
soldering AND designing all day today

Paul Schreiber wrote:

<snip>
> The Input #1 has:
>
> a) 1ea pretty decent (ie "better than your Mackie") mic preamp with
> phantom power, LoZ-HiZ switch. Balanced in, MOTM-level out (at full
> gain).
>
> b) 1 REALLY good RAIA preamp for those big flat black things that
> hold music (so I'm told). RCA inputs, 1/4" outputs.
>
> c) 1 REALLY good headphone amp (99.99% of headphone amps that you 
> have heard are using cheesy JRC4560 op amps for 14 cents).

Well, I guess I would rather have the headphone amp on the output
module.

<snip>
> The Envelope Follower is a dedicated module that assumes MOTM-level
> inputs (and generates MOTM-level outputs). Still in design and
> parts-pondering. Not your boring full-wave rectifier stuff,
> neither :)

Great!  Triple peak detectors?  Or maybe THAT-2252 driven?

George

Ok, so I guess my take on it is..

Makes sense to put a mic pre and a balanced input together into a "nice" input 
module. We don't need a phono pre-amp, as that's always going to be in the DJ 
mixer.

The triple pre-amp will take care of interfacing anything unbalanced at line or 
instrument level.

Headphone belongs on the main output. That's just logical.

I'd like then to also see a second separate unbalanced output w/ attenuator on the 
output module. This could be used to:

1. form an effects loop w/ the pre-amp module
2. output MOTM into a guitar amp
3. interface to some other DI box you might prefer to use

So the output module would have 1 balanced out w/ attenuator, 1 unbalanced -10 
out w/ attenuator, and 1 headphone out w/ volume pot. And of course, the inputs to 
the three circuits would be normaled, but could be used separately too.
I think that would fit? Six jacks and three pots.

So that's 1 pre-amp, 1 input, and 1 output module. Anybody?

One last request. Any chance of getting a transformer on the balanced input? (Gasps 
all around. People freaking out. I'm hiding...)

Max

I think he meant the MOTM level inputs into the output module would be
normalled.   That's the way I took it.
Larry


----- Original Message -----
From: Paul Schreiber <synth1@...>
Kind of hard to normal XLR connectors :)

> And of course, the inputs to the three circuits would be normaled,

> Makes sense to put a mic pre and a balanced input together into a "nice" input
> module. We don't need a phono pre-amp, as that's always going to be in the DJ
> mixer.

OK, I'm punting my nice phono preamp :(
It was a thing of beauty (sob......sniff)

>
> The triple pre-amp will take care of interfacing anything unbalanced at line or
> instrument level.

Correct!

>
> Headphone belongs on the main output. That's just logical.

It does only if you are buying *one* output module. Many folks will want 2-10 output modules, and
they do not want 2-10 headphone amps!

>
> I'd like then to also see a second separate unbalanced output w/ attenuator on the
> output module. This could be used to:
>
> 1. form an effects loop w/ the pre-amp module

OK

> 2. output MOTM into a guitar amp

Eeekkk! Not OK! The output level of "standard" Strat-type humbucking pickups is like 25mv pk-pk.


> 3. interface to some other DI box you might prefer to use
>

> And of course, the inputs to the three circuits would be normaled,

Kind of hard to normal XLR connectors :)

Paul S.

hello again...

> OK, I'm punting my nice phono preamp :(
> It was a thing of beauty (sob......sniff)

unless of course it was a dual phono pre-amp with crossfade and voltage
control !!!

> Kind of hard to normal XLR connectors :)

i think the neutrik combi jack / xlrs have normalling - there's a hell of a
lot of pins on the back...

cheers
paul b

>
> Paul S.
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

"Paul Schreiber" wrote:

> > Headphone belongs on the main output. That's just logical.
>
> It does only if you are buying *one* output module. Many folks will want
2-10 output modules, and they do not want 2-10 headphone amps!

Good point.  So you want to put the headphone amp in the input module,
then? :/  I'm assuming there would be headphone amp input jacks on the
panel?

Alternatively, how about a separate 1U headphone amp module, with:

two pairs of separate L & R MOTM-level input jacks, IN1 and IN2
switch for selecting IN1 or IN2
behind-the-panel normalled connections to two output modules
(output modules would have headphone module connector on PCB)
input jacks would override the behind the panel connections
two headphone output jacks (no more Y-cables!)
single headphone volume control
a 4-way mult

I did a quick sketch and this would fit within 1U.
??
George

>  > 2. output MOTM into a guitar amp
>
>Eeekkk! Not OK! The output level of "standard" Strat-type humbucking 
>pickups is like 25mv pk-pk.

Everything sounds better when piped through a marshall amp with 
leslie cabinet, even MOTM. But it's easy enough to make our own 
custom cable for this application.

just my thought:
it's frustrating not to have a bare functional preamp available at 
the very moment.
i can't afford the 25 input/output modules anyway,
so:
why not release a "basic" yet high-quality mic/line/guitar preamp 
module and an enveloppe follower module first, for us poor people, 
hmm? 
thanks,
gregory

That's *exactly* what the Triple Preamp is. This module is in final design *today* and I'll have
prototype pc boards on the test bench in 2 weeks.

Paul S.

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

From: "grotechef" <grotechef@...>
To: <motm@yahoogroups.com>
Sent: Saturday, August 23, 2003 5:49 AM
Subject: [motm] Re: Different I/O panels


> just my thought:
> it's frustrating not to have a bare functional preamp available at
> the very moment.
> i can't afford the 25 input/output modules anyway,
> so:
> why not release a "basic" yet high-quality mic/line/guitar preamp
> module and an enveloppe follower module first, for us poor people,
> hmm?
> thanks,
> gregory
>
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>

A few people have asked Larry about daughterboards for the 320R and 
120R panels. Since I'm the guy making them, I thought I should post 
an YAU message to the group.

Prototypes for the daughterboards were built and tested back in early 
July. I've had the final boards for several weeks now and am eagerly 
awaiting my own 320R and 120R Stooge panels so I can build, test, and 
document before I begin shipping them out. I will have pictures, 
building instructions, and ordering info on my website (probably in 
two weeks). I'll post another message here when everything is ready 
to go.

Larry was kind enough to let me know who ordered panels. I had enough 
daughterboards made to cover everyone who bought panels this time 
around, plus a few extra to cover those who emailed me saying they 
were going to order panels the next time around. Anything left over 
will be up for grabs.

Here's a teaser shot:

http://www.tellun.com/3_daughters.jpg