I just received an email from AMT. 18V will damage the pedal.
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AMT Brick "Alembic Tube Preamp" pedal
- Thread starter CC7
- Start date
I just received an email from AMT. 18V will damage the pedal.
Your crystal ball is working!!
AMT Bricks A Bass arrived today. Yay.
First, I just exchanged messages with Dmitry Rodin yesterday. Great guy. Immediate feedback and alerted me about the tracking. Really conscientious company.
Second, I plugged the A Bass in;....and initially thought it wasn't working. Why? Because the tube didn't light up the way I'm used to seeing a fully biased 12AX7 radiate photons.
I confess I may need to study this preamp a bit more.
The preamp sounds fine. But, I'm powering it with 1.0A 12 VDC converters; whereas AMT recommends a 1.2A converter. Perhaps my converters are inadequate? The preamp power Jack is labeled 300 mA 12 VDC. And yes, I have proper ring + bias on the input plug. So, everything is correct, except still a Q about the required supply current. Anyhow, bottom line is the tube doesn't look right. My SLO MkIIIs lights up just like it should. Not the Bricks A Bass.
But, as I said, first listening sounds pretty decent, if a bit limited.
That's what I've got for now. Also breaking in a new Mesa TT800. So, may take a little while to get more done. But, initial impression is OK, but with a big Q.
The tube in my O-Bass doesn't glow very brightly, but the pedal does get very hot. FWIW, I'm using a 12V 2A power supply that I had laying around.
Edit: The pedal did get very hot this morning, but I just left it plugged in for 30 minutes, and it was warm when I just checked it.
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A/B time...
Never mind that I firmly inserted my foot in my mouth over in the main Preamp/DI thread (ever wish you could disappear one of your posts which displays utter ignorance?); anyhow, here is an A/B between the AMT Bricks A Bass and the Alembic F1-X.
First, a couple of comments. Preamp/DI's seem to be more designed for their DI capabilities than the preamp function. And, what I mean is that most evaluations reported in this forum focus on tonal aspects of preamp/DI to a digital recording interface, presuming that a signal chain to an FOH board will respond in a similar way. Of course, even that is a whole other discussion. But, my interests include how the little pedals perform driving a power amp into bass drivers.
My initial interest in the A Bass was piqued by the possibility to put a fully functional Alembic preamp on a board to be used with my Alembic Series I bass. More on that later.
So, here's the deal.
What you are looking at is a standard Alembic rack preamp (A) with the rack mount power supply DS-5R (for the bass), and the (much) more portable AMT Bricks A Bass (B) fed by the standard smaller Alembic DS-5 Blue box. The bass is a Series I short scale bass. The power amp is a Demeter Minnie 800D. The cabs are 2X Bergantino HD112's. So, switching the input cable from the bass, and the preamp feed to the Demeter, gives pretty similar signal chains.
Results were that the rack system has noticeably more dynamic content; much more grunt and clarity. Most players would readily hear it. The A Bass is close in character, but lacks that 10% of dynamic capability. Aside from that difference, comparisons get a little dicey; mainly because the F1-X is a 2-8-2 "flat" kind of tone stack, while the A Bass seems closest to "flat" with the tone stack at 5-5-5. Also, the A Bass has a separate Gain knob for overdriving the tube, whereas the F1-X is mainly a Clean preamp. Bottom line, the rack is significantly preferable for driving a backline rig; but, the A Bass is close enough to be interesting.
Disclaimer: Possibly differences in tonal character could be closer if my preamp were instead an F2B? IDK; don't have experience with the F2B.
Since the A Bass is "close enough," I absolutely would consider putting together a board with it. So, Yay for AMT for delivering a nice preamp/DI!
Now, about putting together a preamp board for the Series I Bass: By my calculations, I can get everything I would need to have equivalence to the rack on a Pedaltrain Nano+.
The first thing that would have to go on there is a DS-5 box. Couple of aspects to doing that. The DS-5 is "heavy," and would probably need to be screwed to the board; Velcro won't do. I'm not in a hurry to commit my one DS-5 to a permanent board mount; so, I suppose I will need to bide my time until one hits the used market AT A REASONABLE PRICE. Which could be a while, since recent asking points have been nearly half of what the bass initially cost (gag).
Second, preamp boards for me are all about convenience; which means I don't want to plug in more than one 120VAC supply. Because the DS-5 needs 120VAC, I scoped out this power supply:
https://www.amazon.com/Aetos-120V-C...597333634&sprefix=Walrus+aetos,aps,213&sr=8-3
Which takes up board space on top, but also provides the 120VAC for the Blue Box.
From there, add a tuner and a JDI, and you're good to go at fairly modest cost. Except the 2nd DS-5. Anyhow, the potential is there. I'm thinking about it.
To summarize: the A Bass is a nice little unit. It is similar to the Alembic F1X; but lacks both dynamics and clarity. The A Bass could be used to create a decent portable preamp board for an Alembic Series I/II bass.
Last comment: I'm still not hearing what I need to hear in the pedalboard preamps, such that I will let the racks go. Not there yet for me.
Never mind that I firmly inserted my foot in my mouth over in the main Preamp/DI thread (ever wish you could disappear one of your posts which displays utter ignorance?); anyhow, here is an A/B between the AMT Bricks A Bass and the Alembic F1-X.
First, a couple of comments. Preamp/DI's seem to be more designed for their DI capabilities than the preamp function. And, what I mean is that most evaluations reported in this forum focus on tonal aspects of preamp/DI to a digital recording interface, presuming that a signal chain to an FOH board will respond in a similar way. Of course, even that is a whole other discussion. But, my interests include how the little pedals perform driving a power amp into bass drivers.
My initial interest in the A Bass was piqued by the possibility to put a fully functional Alembic preamp on a board to be used with my Alembic Series I bass. More on that later.
So, here's the deal.
What you are looking at is a standard Alembic rack preamp (A) with the rack mount power supply DS-5R (for the bass), and the (much) more portable AMT Bricks A Bass (B) fed by the standard smaller Alembic DS-5 Blue box. The bass is a Series I short scale bass. The power amp is a Demeter Minnie 800D. The cabs are 2X Bergantino HD112's. So, switching the input cable from the bass, and the preamp feed to the Demeter, gives pretty similar signal chains.
Results were that the rack system has noticeably more dynamic content; much more grunt and clarity. Most players would readily hear it. The A Bass is close in character, but lacks that 10% of dynamic capability. Aside from that difference, comparisons get a little dicey; mainly because the F1-X is a 2-8-2 "flat" kind of tone stack, while the A Bass seems closest to "flat" with the tone stack at 5-5-5. Also, the A Bass has a separate Gain knob for overdriving the tube, whereas the F1-X is mainly a Clean preamp. Bottom line, the rack is significantly preferable for driving a backline rig; but, the A Bass is close enough to be interesting.
Disclaimer: Possibly differences in tonal character could be closer if my preamp were instead an F2B? IDK; don't have experience with the F2B.
Since the A Bass is "close enough," I absolutely would consider putting together a board with it. So, Yay for AMT for delivering a nice preamp/DI!
Now, about putting together a preamp board for the Series I Bass: By my calculations, I can get everything I would need to have equivalence to the rack on a Pedaltrain Nano+.
The first thing that would have to go on there is a DS-5 box. Couple of aspects to doing that. The DS-5 is "heavy," and would probably need to be screwed to the board; Velcro won't do. I'm not in a hurry to commit my one DS-5 to a permanent board mount; so, I suppose I will need to bide my time until one hits the used market AT A REASONABLE PRICE. Which could be a while, since recent asking points have been nearly half of what the bass initially cost (gag).
Second, preamp boards for me are all about convenience; which means I don't want to plug in more than one 120VAC supply. Because the DS-5 needs 120VAC, I scoped out this power supply:
https://www.amazon.com/Aetos-120V-C...597333634&sprefix=Walrus+aetos,aps,213&sr=8-3
Which takes up board space on top, but also provides the 120VAC for the Blue Box.
From there, add a tuner and a JDI, and you're good to go at fairly modest cost. Except the 2nd DS-5. Anyhow, the potential is there. I'm thinking about it.
To summarize: the A Bass is a nice little unit. It is similar to the Alembic F1X; but lacks both dynamics and clarity. The A Bass could be used to create a decent portable preamp board for an Alembic Series I/II bass.
Last comment: I'm still not hearing what I need to hear in the pedalboard preamps, such that I will let the racks go. Not there yet for me.
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Thanks for the real world, direct comparison. I was hoping someone would be able to compare the A-Bass to real Alembic Preamp and, although I take your point about dynamic range, it does indeed sound like the A-bass gets in the ball park and is possibly the cheapest pedal (or any bit of gear, I guess) to do that. I'm very tempted and almost pulled the trigger a few times
I received an A-Bass a few weeks ago and also have an O-Bass. I like them both enough that I bought a new Strymon power supply that will power 2-12VDC pedals. Time will tell how durable they are.
Not sure how the A-Bass compares to the Alembic preamp, but it does have a great EQ section on it. Cranking the gain all of the way up produces a slight overdrive. I use it to clean up one of my "muddy" sounding basses, and I really like it.
The O-bass gets tons more overdrive and has a great EQ as well. Very happy with this pedal as well.
Not sure how the A-Bass compares to the Alembic preamp, but it does have a great EQ section on it. Cranking the gain all of the way up produces a slight overdrive. I use it to clean up one of my "muddy" sounding basses, and I really like it.
The O-bass gets tons more overdrive and has a great EQ as well. Very happy with this pedal as well.
I have one on the way and look forward to getting it.I also have an AMT O-bass that's modeled on the Orange ad-200 bass head on pre-order.This stuff looks very cool.Good C.S. also.
I have the A-Bass and like it quite a bit.I think it'd work ok on a guitar in fact I'm going to try it as one can get a warm clean tone from it.I also have the O-Bass and it's a grit monster with the hairy sound Orange tube amps are known for.
I've had a A-bass for about 4 months and a F1X for about 25 years, and I agree with bucephylus - the A-Bass is about 90-95% of a sound of a F1X. That doesn't mean it sounds bad - it really sounds good! I'm totally happy using it as a preamp and it really gives that tubey midscoop sound with bass/mid/treble flat ("flat" as in all set to 5, which is still a big bass/treble boost and mid cut) in a super small pedal. cranking the gain does give a bit of hair on the sound but thats about it, so don't expect even a OD level of grit (at least with the tube in mine, reports are you can change that tube for a grindyer sound). Note it doesn't have the bass boost, transformer DI or the crossover on it like the F1X does. I've been playing into a Effectrode LA1 --> A-bass --> focusrite interface and it sounds great.
I think the broughton super-stack is a competitor as well, but the last one on reverb was $350, which is about $125 more then the a-bass. I haven't heard it but broughton has a great reputation - i have their messenger preamp and it is excellent.
I think the broughton super-stack is a competitor as well, but the last one on reverb was $350, which is about $125 more then the a-bass. I haven't heard it but broughton has a great reputation - i have their messenger preamp and it is excellent.
I've just had a quick test run with the A-Bass and it sounds great. It's got a nice, rounded, fat tone (I use flatwound strings for an old-school tone so the A-Bass complements that perfectly). I'll post a full review when I've used it more but for now it's two thumbs up!
PROS - very good core tone, very usable range on the controls (gain doesn't get into raging hellbeast levels but does get pretty gnarly turned up full), really solid construction, tiny size, versatile (option to be used in a pedal chain or as a preamp).
CONS - used direct it has harsh top end overtones when not outputting through a cab sim (when used with a good cab sim it sounds amazing).
I've noticed how the A-Bass responds to different basses.I own many basses and it's fun how the preamp brings out the timbres of each.It is surprising how much more grit my Steinberger gets compared say to my Jazz Bass.The A-Bass gets thumbs up from me.Want something really knarley? Try the O-Bass, it's a grit monster! I'm powering them via a Cioks 18v outlet and an Alctron DCT 500 power supply.I came across the Alctron on Reverb and I was so impressed I bought it.It has 6 outputs and can accommodate 2 x 18 or 12 volt pedals or 6 x 9v.Built like a tank for $85.00.I have power supplies by Voo Doo Labs ,Cioks,T-Rex and Walrus Audio and this one stacks up to them for less than half the price.
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I ordered mine off the AMT website on two different occasions and had them in about 2 weeks.All the way from Mother Russia to Lil' Rhody.
That's an impressive review.AMT should use you as an endorsement.
Zombie thread resurrection - howz the AMT O as compared to the A? I understand they have similar (same?) Tone stack and the A has a few additional options ... The O has more gain, correct? Can the A get dirty at all? Any other thoughts on the differences? I'm gonna pick one up, just trying to decide on which one. Leaning towards the A for the options ....
Edit: pulled the trigger on an A. Now someone talk me out of getting an O ....
Edit: pulled the trigger on an A. Now someone talk me out of getting an O ....
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I have both, and they are great pedals. The O does dirty really well, and the A will get mildly gritty depending on the pickup and signal gain before it. Obviously, if you run a hotter signal into the A, it will get dirtier. They both sound great, but in different ways as the A is cleaner, while the O can be dirtier sounding (it does clean up quite well) and will get heavier distortion. I have since replaced both pedals with the Sushibox FX Particle Accelerator and London Undergound pedals, as they run on 9 or 12VDC and sound just as good. If you want to buy my O-bass pedal, send a DM my way.
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The A is capable of me mellow settings not to say it can't be gritty while the O gets very nasty at high gain settings but can clean up.They bring out the characteristics of different basses nicely.I dig em'.
I might take you up on that. I have a Particle Accelerator coming as well, but I haven't really messed with any Orange clones.
Would you happen to know of a 12v power adapter other than the one AMT offers? It seems rather expensive and also shipping cost.I use my iso power bricks but I'd like an adapter for the times when it's more convenient.I bought one off eBay with specs as close as I could find but it works with some pedals but not the A bass.
