Should I use this with built in dlator?

[dogears]

Guys, why are we still debating here? Gil was in the amp.

The network is out of circuit when the loop is used. The brown wire is connected to the send jack and not the return jack.



The little resistor and cap in parallel are connected to the switching lug of the return loop jack. So, when the loop is used, the network is out of the picture all together. I did hear the amp as is, VS patched with a short cord in the loop... and noticed that the network adds a little bit of treble to the sound of the amp. When using a Dumbleator, you get a choice of two bright switches on it, so I guess Dumble figured the owner didn't need a permanent brightness network all the time.

Gil

[Max]

Guys, why are we still debating here?

IMO:

In most human communication misunderstandings of all sort are more prevalent than understanding. In internet discussions the sistuation is even worse because many channels of communication are not present in internet communication. Some here are no native english speakers. The topic is complicated. Data base here is sometimes confusing and even contradictional. Hard to keep track of revisions of layouts and schematics.

Because all of this and more I think, that for internet discussions one thing is of uttermost importance - patience with each other.

Cheers,

Max

[talbany]

Hi , maybe my questions is stupid , in the schematic #094 , the 220K/500Pf network before V1B is omitted the cap , this network has same function of the S/R loop ? why the cap is omitted there?
thanks

Grid resistors serve 2 main purposes
1 keep stray RF from entering the grid
2 Tone shaping

If your blocking RF a 56k covers the spectrum..when you get up to around 120k your now entering tone shaping territory..The 220k cuts some gain tightens the low end and without the bypass cap attenuates highs..(in conjunction with the miller effect)
If the tone you seek is brighter w added sizzle on the top add 500pf ceramic.. If it's warmer with less presence axe the cap..
Someone chose warmer

I like the whoop de do

Tony

[markusw]

this network has several functions

1 Helps with signal transfer
2 helps with the loading on the PI
3 shapes tone (low frequency response)
4 can have a smoothing effect

This is not to say that you will like it better without it but this is what it does in theory..You asked

Tony

Hey Tony,

sorry for another dumb question
What does loading on the PI mean and how does the network help?

Thanks for your patience!

Regards,

Markus

[Sonny ReVerb]

I like the whoop de do

Well, sorry, dogears says you have to change it back.

The network is out of circuit when the loop is used. The brown wire is connected to the send jack and not the return jack.

[martin manning]

The revised layout is correct- the parallel RC is out of the signal path when the loop is NOT in use. I wonder if there was a thought that the send jack could be used as a line out, in which case the network would serve as some kind of speaker emulator??

[dogears]

Thanks for the picture Martin. I could not find mine. I was basing my comments on the original thread where Gil describes the network. So, I guess I stand corrected. I wonder why Gil thought it was the other way?

Regardless, I would not use this network. It seems to be the exception and not the norm.

The revised layout is correct- the parallel RC is out of the signal path when the loop is NOT in use. I wonder if there was a thought that the send jack could be used as a line out, in which case the network would serve as some kind of speaker emulator??

[martin manning]

You're welcome. Gil's words as you posted were indeed a little confusing; I had to go back and study the picture closely again to reconfirm!

[talbany]

this network has several functions

1 Helps with signal transfer
2 helps with the loading on the PI
3 shapes tone (low frequency response)
4 can have a smoothing effect

This is not to say that you will like it better without it but this is what it does in theory..You asked

Tony

Hey Tony,

sorry for another dumb question :oops:
What does loading on the PI mean and how does the network help?

Thanks for your patience! :)

Regards,

Markus

Let me put it this way..

In a low-level signal application, you want maximum voltage transfer, not maximum power transfer, so the "ideal" situation is a zero output impedance from the driving source going into an infinite impedance for the receiving end.

Example

Let's say the Dumbleator send impedance is roughly 1K ohms is fairly low, so it is near "ideal" for lets say a 1Meg input impedance of an outboard effect device, so they are a good match because you will not lose any appreciable amount of voltage - if the Lator puts out a 1V signal, you'll get 0.999 volts at the input to the effect

The output impedance of the effect can also be fairly low, so driving into the return of the amp, which presents a 220K load (the network we refer), you'll only lose a small (or smaller) amount of voltage - once again better-matched...

Without the loop (in this configuration) the Pi sees a 1M load (Master) or slightly higher ..In order for the PI to function in the same manner with the loop connected it also needs to see a 1M load (or fairly close) when using a loop.. That network helps (but not critical)

Remember TONE trumps all here!!..If you like the tone better without the network.. Yank it..

Hope this helps..

Tony

[markusw]

Let me put it this way..

In a low-level signal application, you want maximum voltage transfer, not maximum power transfer, so the "ideal" situation is a zero output impedance from the driving source going into an infinite impedance for the receiving end.

Example

Let's say the Dumbleator send impedance is roughly 1K ohms is fairly low, so it is near "ideal" for lets say a 1Meg input impedance of an outboard effect device, so they are a good match because you will not lose any appreciable amount of voltage - if the Lator puts out a 1V signal, you'll get 0.999 volts at the input to the effect

The output impedance of the effect can also be fairly low, so driving into the return of the amp, which presents a 220K load (the network we refer), you'll only lose a small (or smaller) amount of voltage - once again better-matched...

Without the loop (in this configuration) the Pi sees a 1M load (Master) or slightly higher ..In order for the PI to function in the same manner with the loop connected it also needs to see a 1M load (or fairly close) when using a loop.. That network helps (but not critical)

Remember TONE trumps all here!!..If you like the tone better without the network.. Yank it..

Hope this helps..

Tony

This definitely helps!
Thanks a lot for your explanation!

Regards,

Markus

[Structo]

How about this one.
I see, for example on the ODS 101 nonHRM, shows a 100K resistor in series with the preamp out or Send .
It is wired so it is in the circuit regardless of the loop being used.
Is this an attempt at matching impedances better?

[talbany]

How about this one.
I see, for example on the ODS 101 nonHRM, shows a 100K resistor in series with the preamp out or Send .
It is wired so it is in the circuit regardless of the loop being used.
Is this an attempt at matching impedances better?

Tom
I can't really see how this would be a load balancing resistor since it precedes the buffer?.. I imagine it would be there for tone balancing or smoothing of the top end kinda tweak more than anything..Resistors here can also help filter some noise in high gain pre amps..

Tony

[Max]

this network has several functions

1 Helps with signal transfer
2 helps with the loading on the PI
3 shapes tone (low frequency response)
4 can have a smoothing effect

This is not to say that you will like it better without it but this is what it does in theory..You asked

Tony

Hey Tony,

sorry for another dumb question
What does loading on the PI mean and how does the network help?

Thanks for your patience!

Regards,

Markus

Example

Let's say the Dumbleator send impedance is roughly 1K ohms is fairly low, so it is near "ideal" for lets say a 1Meg input impedance of an outboard effect device, so they are a good match because you will not lose any appreciable amount of voltage - if the Lator puts out a 1V signal, you'll get 0.999 volts at the input to the effect

The output impedance of the effect can also be fairly low, so driving into the return of the amp, which presents a 220K load (the network we refer), you'll only lose a small (or smaller) amount of voltage - once again better-matched...

Without the loop (in this configuration) the Pi sees a 1M load (Master) or slightly higher ..In order for the PI to function in the same manner with the loop connected it also needs to see a 1M load (or fairly close) when using a loop.. That network helps (but not critical)

Remember TONE trumps all here!!..If you like the tone better without the

Tony,

is there any reason, why you did chose such an (IMO) unlikely example?

Why should someone use his Dumblelator only between pre-out and Fx-in and not between Fx-out and power-in?

I understand your arguments but not why you did chose this (IMO) very unlikely example for clarification?

Cheers,

Max

[talbany]

Max
Not sure I understand? what you talking about.. bypassing the return amp?..

Why would you want to do this?..Confused..Internet
I speak of standard Dumleator implementation

Tony

[Max]

Max
Not sure I understand? what you talking about.. bypassing the return amp?..

Why would you want to do this?..Confused..Internet
I speak of standard Dumleator implementation

Tony

Hi Tony,

probably I did not understand your arguments and/or your example:

The output impedance of the effect can also be fairly low, so driving into the return of the amp, which presents a 220K load (the network we refer), you'll only lose a small (or smaller) amount of voltage - once again better-matched...

In "standard Dumblelator application" the "output...of the effect" is not connected with the "return of the amp" but with the return of the Dumblelator.
And then the output of the Dumblelator is connected with the "power amp in" of the amp.

So why do you write:

The output impedance of the effect can also be fairly low, so driving into the return of the amp

This I don't understand because in standard Dumblelator application (based on my current understandig) the network refered to in this thread does not present a 220k load to the output of the effect, as you wrote (at least in my current understanding of what you wrote), but to the output of the Dumblelator?

Where is my misunderstanding?

Have a great http://www.youtube.com/watch?v=FECFb1_YdII

Max