Shouldn't every ODS clone have a built in Dumbleator?

[Mark]

I've seen the various D style amp layouts. Some people build the effects loop into the amp while others choose to build a stand alone Dumbleator.

Perhaps I don't get it, but the loop is to prevent signal level losses and fidelity losses. In which case you want short leads to the loop and long-ish send/return leads are permissible.

What is the consensus on the effects loop?

[martin manning]

Some people have said it’s an essential part of the system, but I don’t agree. I see no problem with putting effects out front, and when using the loop I did not need to reduce highs with long cables. I only have one amp and a stand-alone D’lator, though. Marcus probably can help here with his recent experience.

[erwin_ve]

A external Dlator for a buffered FX loop seems like some kind of prototype experiment gone commercial.
My preference is to have a Dlator built in the amp for several reasons:

Less loss of highs. With a outboard Dlator both send(from amp) and the return stage(from Dlator to amp) are high impedance and the loss of highs is a logical consequense when using longer cable.
When not using the dlator as a FX loop you still can have a benefit when it's built in: driving the cathode follower real hard is giving a nice compression and overtones, very much like a loud amp. Very useful for smaller stages where volume is a issue.
Less stuff to take to a gig.

[Mark]

Thanks for the replies.

Martin, I get it when people say it is an essential part of the amp. If you put a moderate signal through the amp it doesn't make as much of a difference, however if you hit the cathode follower hard it does thicken up the tone of the amp. The bright switches on the Dumbleator also offer a bit more tone shaping.

I came to these conclusions building up a Brown Note amp to Robben Ford specs. The Dumbleator made it sound R.F. like.

[norburybrook]

Sorry, late to the party on this.

It's interesting that Robben Ford hasn't used his dumbleator now for close on 10 years. I doubt there's anyone that knows his amp like he does and it's range of tone. he puts everything I front of the amp now and obviously doesn't think he looses anything with that. I was working with Mark Knopfler a few weeks ago and he wont use FX loops either, everything is in front of his amps.

Personally, it depends on what I'm doing and which pedal board I take. If it's a grab and go gig I usually just take a Strymon flint and a delay pedal and have it in front. Studio sessions with cartage I'll take everything. When I recorded my own album earlier this year I didn't use any FX at all when recording and added reverb and delay post production.


I do like the versatility of the Dumbleator, it's extra tone shaping with the two bright switches is a nice touch as it's more subtle than the bright switch on the amp but I don't think it's a necessity for tone. I can guarantee all the best RF tones you here on his records were recorded dry without the dumbleator.


It is a PIA having a separate 'box' so I would say if I ever built another and could get a 4 hole chassis I'd probably build a buffered loop in for convenience. I think most people have built without as a way of trying to capture the original flavour of the amps. People have gone to great lengths to re create #102,#124,#183 exactly so putting another valve and it's circuitry in would completely negate that.


for convenience I think you can build a small solid state buffered loop and have it on your pedal board, that's another option to drive your delay/reverb pedals properly in a loop.

http://tagboardeffects.blogspot.com/sea ... el/Utility


M

[martin manning]

A stand-alone D’lator is an interesting thing to experiment with, being a cc gain stage and a cf stage that can be used independently. You can for example plug a guitar into the cc gain stage and send it’s output to the amp’s input jack as a tube boost.

[talbany]

I've seen the various D style amp layouts. Some people build the effects loop into the amp while others choose to build a stand alone Dumbleator.

Perhaps I don't get it, but the loop is to prevent signal level losses and fidelity losses. In which case you want short leads to the loop and long-ish send/return leads are permissible.

What is the consensus on the effects loop?

Mark
In general, time-based effects, such as reverb, chorus, and echo need to be added after distortion to sound natural (Just like our pedalboard). This is virtually impossible to do in an amplifier designed to get it's distortion from the output stage. Amps like the ODS that get their distortion from the preamp section will function much better with an effects loop, because the output stage is designed to run clean, so the effects can be used to better advantage. It is true however the 1 tube buffered loop design like the Dumbleator is to prevent signal loss it's not without its design faults.
As far as building them inside the amp here is what I have found!
Typical effects take either guitar level signals or line level signals. In order to avoid overloading the input of these devices with the signal levels in a typical tube guitar amp (which can range from a few volts p-p to a few hundred volts p-p,), you must attenuate the signal going to the effects device and then amplify the return signal back up the the original level. This attenuation-amplification process increases the noise floor of the signal, so the amplifier will be noisier. So with that being said we then should consider the placement of the loop. Since the return signal can be a very low-level signal, bringing it back to a later stage in the amp near the large amplitude signals and output/power transformers can cause unwanted coupling if the circuitry is not well shielded so obviously this is where building the unit separate from the amplifier can provide a lower noise floor and cleaner signal. There are also other factors to consider with respect to problems to ground loops when installing it inside the amp chassis where other multiple ground sources exist!

As far as Tone is concerned (with a serial loop) I can write a paper but will state the obvious!
Cathode followers when driven hard generate 2nd order so there is your thicker tone.It can also provide a bit of compression some people like.
Since the PI sees a bit less of a load (250k Mstr) and lower impedance driving the pot (one of the reasons why Mstr's work better on Marshalls, than SF Fenders) you will also notice a flatter frequency response and better control over the global master.
It also provides a more transparent effects signal mixing when switching between clean and OD where the p-p signal level is increased dramatically like in the ODS. So when you switch to OD your signal doesn't become wet with reverb/delay.
The bright switches are always a plus especially live when you want to brighten things a bit on the fly I use mine all the time.
Those are the main ones IMO.
As far as cartage goes. I If I use any time-based effects I have to bring my time-based effects, usually put in a rack of some sort.So for me the only inconvenience is a slightly larger 1U rack case and the added weight of the Dumbleator.Everything is already wired inside the rack so all I have to do is plug in the amps send and return cords plug in the rack and flip it on

BTW.As far as needing the loop to sound more like R.F,

Tony

[burntfingers]

Hi...new guy here...please excuse the dumb questions.

Would it be fair to say that...
> if you were to use a dumbleator for the tone shaping characteristics only (not as a true effects loop)
> that at stage volume, you would not see that much difference in the tone change?

I've been reading about the effects of the dumbleator on the amp and I'm interpreting that the tone shaping benefits happen a lower volumes...maybe I'm mistaken.

[norburybrook]

Hi...new guy here...please excuse the dumb questions.

Would it be fair to say that...
> if you were to use a dumbleator for the tone shaping characteristics only (not as a true effects loop)
> that at stage volume, you would not see that much difference in the tone change?

I've been reading about the effects of the dumbleator on the amp and I'm interpreting that the tone shaping benefits happen a lower volumes...maybe I'm mistaken.

because of the extra volume control you have on the dumbleator then you can drive the signal to the tone you want and still keep the level down so again the dumbleator is handy for that at any volume.

Martin Manning has a design for a small box Dumbleator, I have one of those. It fits in my Cable/strings/gig crap bag so it's easy to carry.


The 1 u rack version really only makes sense if the rest of your FX are rack mounted this day and age the high end stuff like Eventide H9- Strymon-etc are all pedal format so no need for racks anymore.


it is possible to fit the smaller dumbleator into a slightly larger head cabinet too so that's anther option if you only have one amp I did that but then built two more so need the flexibility to use it with any amp.


M

[burntfingers]

Thanks for the reply...that makes a lot of sense.

I had a Carol OD2 and the effects loop was essentially the master volume. You could get things cooking where you like and then adjust the level that way.

Looks like I better figure out the best way to add one to the amp.

I don't think the Ceriatone layout has room to add one internal...

[talbany]

The 1 u rack version really only makes sense if the rest of your FX are rack mounted this day and age the high end stuff like Eventide H9- Strymon-etc are all pedal format so no need for racks anymore.

Marcus
Checking out the H9 appears not to have a line level input?..So I am confused? are you talking about using the H9 in the loop or in the front of the amp?..If you run it in the front don't you run into problems with having too wet a mix when you switch to the OD side due to the added gain or are you just hanging on the clean side and use the floor for everything like how Robben runs his rig now.
BTW.I can never get low-level inputs on floor boxes to sound good in my loop because the signal gets too squashed at the front end of the pedal and have to jack the signal up after it.(series loop)
I know in the studio at really low vol levels I could maybe make that work but I can never seem to get it to sound or feel good at loud gig volumes I sometimes play.
Not trying to be a pain.Just wondering how you run it,or if I am missing something!

Tony

[norburybrook]

The 1 u rack version really only makes sense if the rest of your FX are rack mounted this day and age the high end stuff like Eventide H9- Strymon-etc are all pedal format so no need for racks anymore.

Marcus
Checking out the H9 appears not to have a line level input?..So I am confused? are you talking about using the H9 in the loop or in the front of the amp?..If you run it in the front don't you run into problems with having too wet a mix when you switch to the OD side due to the added gain or are you just hanging on the clean side and use the floor for everything like how Robben runs his rig now.
BTW.I can never get low-level inputs on floor boxes to sound good in my loop because the signal gets too squashed at the front end of the pedal and have to jack the signal up after it.(series loop)
I know in the studio at really low vol levels I could maybe make that work but I can never seem to get it to sound or feel good at loud gig volumes I sometimes play.
Not trying to be a pain.Just wondering how you run it,or if I am missing something!

Tony

Tony,

My H9 is on my main board so it's on an FX loop chain with other time/modulation FX that goes into the Dumbleator.

If it's grab and go I use a Strymon flint, TC nova delay in front of the amp.

IMG_20171120_104915.jpg

IMG_20171121_101056.jpg

IMG_20171120_104854.jpg

Marcus

[burntfingers]

Has any one tried the Tube Town dumbleator?

https://www.tube-town.net/ttstore/Kits/ ... :7376.html

[norburybrook]

Has any one tried the Tube Town dumbleator?

https://www.tube-town.net/ttstore/Kits/ ... :7376.html

the mounting holes are the wrong width size for a standard Dumble chassis.


M

[burntfingers]

Well crap...however I see they sell a power supply too. It seems like this would be a quick and cheap way to build an external dumbleator.

https://www.tube-town.net/ttstore/Kits/ ... -Converter

Sorry if this has been covered already