Fractal Audio AMP models: Bludojai (Bludotone Ojai)

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Bludojai: based on Bludotone Ojai

This model is based on an amp owned by forum member @austinbuddy.

Austinbuddy reviewed this article before publishing. Thanks Austin! I'm sure he will jump in with more information and tips.

The Ojai is an exact copy of a specific Dumble Overdrive Special amp, used by Robben Ford. When you Dumble, you say Robben Ford, and vice versa. It’s sort of an authorized clone: Robben Ford owns and sometimes plays a Bludotone Ojai, in addition to his famous “Tan” Dumble ODS.

A Dumble is THE most expensive amplifier available, no.1 of Vintage Guitar’s list of most valuable guitar amps. There’s a combo on Reverb.com at the moment with an asking price of more than € 80.000.​

Other famous Dumble players include Larry Carlton, John Mayer, Carlos Santana, Keith Urban, SRV, Eric Johnson, Joe Bonamassa.​

There’s always a lot of talk on the forums about Robben Ford's Dumble tone. It’s an elusive tone, worshipped by a lot of jazz / blues / fusion players. It's a thick, mid-heavy, smooth lead tone, very touch-sensitive. The “note flip” is a certain tonal characteristic attributed to the Dumble and some of its clones. So what’s the note flip? Quote: “It sounds KIND of like its starting to feed back, but its not. It flips the note up so that a different harmonic order is heard, or something like that”.
That trademark tone is not for everybody: hit a power chord and it may terrible to your ears.

By the way, there’s more to Dumble than the Robben Ford sound. Each Dumble was voiced specifically for its buyer, by Alexander Dumble.​

Replicating an original Dumble amp is hard. The amp’s circuit often has goop all over it, hiding the electronics.​

The Ojai is a 100 watts amp with 6L6 tubes. Ojai is the name of the city where Robben Ford lives. The Ojai is part of Bludotone's line of Bludo-Drive amps.

From The Gear Page:

"The Ojai is an exact copy of Dumble #102. Robbens tan Dumble. It also requires the Dumbleator and specific capacitance cables to run to and from the Dumbleator (about 180-200pf per cable). This due to the large bright cap on the amp master. All controls are marked in silver sharpie for the exact settings of Robbens tone. The pot tapers are all 30% audio taper, except the treble control, presence, and the OD in/outs which are linear. Robben sets his mids at about 70K from ground.”​

The Ojai has two inputs: FET and normal. The FET input has a different impedance. The models are based on the Normal input.

The amp has two channels: clean and overdrive.

The Clean model is based on the Ojai’s clean channel with Preamp Boost (PAB) turned on, which makes it kind of crunchy. To get the equivalent of the clean channel without the PAB, change the Tonestack to: Skyline. Also dial back Input Drive to about 1.5 or 2.0, or dial down the Input Trim to .500. You might also want to increase Preamp Dynamics from the default value to 0.5 for more “touch responsiveness.”

There are two models of the OD channel: one with the PAB engaged (Lead 1), and one without (Lead 2). If you are on a quest for the Robben Ford tone, start with Lead 2.

The controls on the original amp are: Volume for each channel. Shared tone controls: Treble, Middle and Bass. Overdrive on the OD channel. Master Volume and Presence.

The switches work on both channels. "Bright" adds spark, it's less noticeable when the volume is turned up. "Mid" boosts mids for more gain, like the FAT switch in the model. And there's a "Rock/Jazz" switch. "Rock" means no filtering is applied. The "Jazz" setting applies high-pass filtering for a darker tone.
On the real amps the first two switches are often turned off, and Rock/Jazz is set to Rock, so the models were created like that. There's also a footswitchable Preamp Boost (PAB). It boosts some mids and adds gain.

There are two gain controls for the OD channel: Volume and Drive, modeled as Input Drive and Overdrive. On all amps like this, including those by Engl, Fryette, Carol-Ann and Mesa, the first control sets the “sensitivity” and the second one sets the amount of distortion. Cliff:

“Input Drive increases the gain amount as you rotate the knob clockwise. As the gain increases the tone is shifted from a treble and upper mid emphasis, which produces an up front sparkling tone, to a lower mid and bass emphasis, which produces a thick meaty tone.​

Overdrive increases the gain amount as you rotate the knob clockwise but with no alteration of the tonal balance.​

Different combinations of Input Drive and Overdrive settings will have a dramatic effect on the response of the amplifier and the personality of your instrument. It is easy to get familiar with the action of these controls and you’ll be amazed with your ability to make any guitar sound mellow, fat, soulful or aggressive.”​

Models with Input Drive and Overdrive controls always feel “elastic” and spongy, a real joy to play.

It’s a Master Volume amp. This means that the amp’s distortion is created in particular by the preamp tubes, not the power amp. The Master Volume, which works in the power amp section, is still very important to the tone and feel. You have to decide for yourself what setting in the model works for you best. The default setting is a good point to start of course. Master Volume has a bright cap switch on it: if you turn it down, it gets brighter to compensate.

Austinbuddy’s comments on the Ojai models:

"The model is of a 100w 6L6 BludoDrive Ojai by Bludotone amps. The Ojai has the same schematic as the famous "Tan" boutique amp played by Robben Ford (Rumble)."​

"The Bludojai is a Robben Ford voiced amp. The clean channel is pretty gainy. So here are some tips, some of this is in the Amp Wiki too.
For the Bludo CLEAN amp, take the tone stack from "default" and replace it with either the Skyline or Skyline Deep tonestack. Next, set the master volume to 5 (it has a brite cap on it, so the louder the master, the less trebly; Ford sets his around 5). Next, set the Drive control to literally 1 or 1.5 - pretty low, and the guitar input gain control to 0.5. (Think about how Robben constantly uses that volume pedal to control the amount of guitar signal going into the amp...this gives you some room). Now you have a very nice sounding Dumble Fender on Steroids with mids clean, with Bass at 5, Mids at 3-5, treble at 5, presence at 3-5. Jack up the Level output volume to compensate for the lower gain settings. Pair it with a G12-65H speaker. Cab Pack 17 has many choices (full disclosure, I produced 5 of the 6 Cabs in that Cab Pack). The BludoMix Cab in factory firmware is a 1x12 Alnico dual port cab, and will sound good but perhaps a tad darker (great for Jazz) on clean sounds than the G12-65H will. Now, if you like, put a Zen drive in front on the BludoClean amp....or a boost...and listen to how that clean channel wakes up fast for grittier leads and touch-responsiveness.
For BludoLead, take the Lead default amp values. Put the Master Volume on 5. Put drive at 4-5 and Overdrive at 4-5, and experiment with the tone stack swaps above. If you want the amp to feedback effortlessly on a note, raise the overdrive setting higher combined with the gain, provided you have sufficient volume coming out your speakers to hit your guitar pickups in a reinforcing loop, it will do it! Throw a boost or Zen drive on that, if you like...”​

About the cabs: for the Robben Ford tone, you'll need the G12-65. There isn't a recent, good-quality near-field IR of a G12-65 among the stock cabs. But you can get them in Cab Pack 17: Buddy's Boutique, which was produced mostly by Austinbuddy. Austinbuddy:

"Cab Pack 17 also has the oval-back 2x12 cabinet with Celestion G12-65H speakers which Robben uses live. Be sure to play with the speaker resonance in the amp block (lower it to around 75-85) to compensate for the open-back cab and get your bottom end correct!"​

Cab Pack 16 ML Suhr also has G12-65 IRs. OwnHammer has some too.

Alexander Dumble himself liked the EV-12L. Check out stock cabs #008 and #105 if you prefer that sound. There are more EV-12L IRs in Cab Pack 17.

Alternatively try stock cab #011. It's the IR of Buddy's dual-ported 1x12 closed-back cab. While Larry Carlton uses an old EV-12L in his, this one uses a modern replacement for an EVL-SRO, a Blackhawk AlNiCo WGS. There are more IRs of this cab in Cab Pack 17.









 
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I will definitely try this with the suggested settings and other advice. I have never played anything Dumblesque in real life, so it was one of the things, I was looking forward to when getting the Ax8. I was a little bit disappointed, when I first tried them, but now that I have a better idea of, what I should be doing, I will give it another go
 
Yek - thanks for a great write up on the Bludotone Ojai and big thumps up to @austinbuddy for letting Cliff model the amp and for providing info on it, respect to both of you :)

Robben Ford is one of my all time favorite players, I love the Dumble tone and one of the few amps I have left is a very very good Dumble clone (Mystic Blues ODS with Cat-u-lator).

Since Quantum FW was released for the Axe Fx, I think that the Dumbles in the Axe is off the charts good, and I've gotten great Dumble tone by just slightly modifying the ODS-lead and ODS-clean presets for my gutars and fingers.
I've only shortly tried the Ojai model, always meant to come back and give it a real work through.
So I guess I'll take this thread as a poke with a cattle pod and make sure to dive deep into this amp when time permits later this week and experiment with it and it's tones :)
 
Since 2.01 and the acquisition of a new cab (FAD, handbuilt in Belgium, 212 open back with Jensen Tornado and Blackbird), I'm mainly using Dumble style models. I like smoothness and sustain, and these have it. The one I use most is more a far cousin though, the TwoRock. But this one is great too
 
Thanks so much for this thread...this post in particular has inspired some amazing new early-AM tones from this amp..and allows me to rediscover the glories of CAB PACK 17!!
@austinbuddy hope our paths cross again....maybe at the RobbenFordZilla at Full Moon Resort............
 
Does anyone know:Do the models in the AF2 have that "note flip" quality and if so how do we dial it to really get it? What are the differences in the Rock/Jazz switch, and how do we do that in the AF2? And lastly what's the difference in the Normal/FET inputs?

I love that Yek is doing this, I've discovered that I like some amps that I may have moved on too quickly from, and if nothing else they're very fun to read. One thing I've noticed is that there seems to be less info in the posts on the higher gain amps, is that because there is just less info to be had? Either way I am loving this, I look forward to it every day! Yek you are awesome!
 
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Does anyone know:Do the models in the AF2 have that "note flip" quality and if so how do we dial it to really get it? What are the differences in the Rock/Jazz switch, and how do we do that in the AF2? And lastly what's the difference in the Normal/FET inputs?

I love that Yek is doing this, I've discovered that I like some amps that I may have moved on too quickly from.

Normal/FET is covered in the OP, it's an impedance difference.

Rock/Jazz: "Rock" means no filtering is applied. The "Jazz" setting applies high-pass filtering for a darker tone.

Note flipping: I think you'd have to find out yourself. I'm not even really convinced this is strictly a Dumblesque thing. :)
 
Have tried the three bludotone versions in the axe with the bludo stock cab.

Very nice cleansounds with a paula!

I´ve searched for the difference between lead 1 und 2 - the second has got tonestack pre - so there´s less gain, but more "flip" mojo? sounds better to me than the first with more gain.

with stock G12-65 IR´s it sounds terrible to me...........
 
I was fortunate enough to see him and Danny Gatton on the same bill, back when Talk to your Daughter came out.
One of the best sounding and amazing concerts I have attended.

thanks for the info yek!
 
Great write up, as usual.

One thing about this amp and the other ODS type amps that I am finding, and I'd be curious to know whether others are finding the same. I used to try to use the bass knob to roll off the wooly, tubby bass on Lead 2. But rolling it down to the 2-3 range had a drastic effect on the midrange knob's sensitivity, too. As in it became hard to hear it doing anything, especially on the Ford amps.

Using the cut function under the bass knob seems to let you keep the bass knob up, letting the tone stack act more as I would expect it to but without being too boomy.
 
I had ignored this amp before, but today I ended up mixing it with a Plexi 100 jumper and it's my new main Southern Rock patch. Killer tone for Allman Bros, Marshall Tucker, etc... great control with volume knob on guitar and can also play a nice thick clean or crunch based on finger dynamics. I'm twiddling with studio compressors after amp before cab to reduce the volume change when going clean to grit with finger dynamics or guitar volume knob. Something is lost when I do that (I wasn't happy with the amp model output compression which is why I tried separate modules), still have some tweaking to do there. But honestly, the times I need to go from loud cleaner to same volume grit I'll use a scene change because I can do that easily with a footpedal, but I suck at trying to twist the guitar volume knob and not having a late entry to the transition part of a song.
 
I had ignored this amp before, but today I ended up mixing it with a Plexi 100 jumper and it's my new main Southern Rock patch. Killer tone for Allman Bros, Marshall Tucker, etc... great control with volume knob on guitar and can also play a nice thick clean or crunch based on finger dynamics. I'm twiddling with studio compressors after amp before cab to reduce the volume change when going clean to grit with finger dynamics or guitar volume knob. Something is lost when I do that (I wasn't happy with the amp model output compression which is why I tried separate modules), still have some tweaking to do there. But honestly, the times I need to go from loud cleaner to same volume grit I'll use a scene change because I can do that easily with a footpedal, but I suck at trying to twist the guitar volume knob and not having a late entry to the transition part of a song.

On compression, on thing I find very helpful is putting a studio compressor at default value before the amp block (usually first in chain but after wah), then turning the mix control to somewhere between 36% and 50%, so it blends straight and compressed sound -- helps you get sustain without sounding like a compressor is on at all. I never fool with the amp compression knob myself. You can try this trick after the amp block as well. See if that helps.
 
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@ Yek thanks I just want to sell it and leave .
I want some food and a passport.. Hoping to kill some Rats this year .
I have no interest in hearing anyone play or staying elevator music bores me to sleep.
If the auction was this month Id not even go.. But it is what it is...
 
Coincidentally I happened to visit Ojai ( in California) last week while vacationing along the central coast...was not aware Robben Ford lived there. Nice little town tucked away in a valley ( Tuscany - like mountain setting) - about a 20 minute drive from the coast.
 
Note flipping: I think you'd have to find out yourself. I'm not even really convinced this is strictly a Dumblesque thing. :)
Nor am I. A couple of years ago, I could only find four references to the "flip," and three of them were people asking questions about the first one. From the audio examples that were posted, it sounded like what you'd get from a player who's skilled at pick dynamics, playing through a very responsive amp.
 
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