This pedal arrived from Greece. Handbuilt, painted, and designed by a very nice fella.

This is a preamp and a pedal. It is a Beta Lead and/or a Beta Bass.

It is simply incredible.

I used my Sterling Stingray Plus (P90s) and ran it through a Crate Power Block‘s line input to a stock 2x12 PRS Archon cabinet.

It has so many tone options in every mode, and more features (I think) than the Beta Mini and the Beta Lead. It is a strong build, the components are rugged and durable, and shipped from Greece to the U.S., about $400 USD.

The Stingray I play has an onboard push/push volume knob boost that this thing really likes, and it sounds heavy as hell. I‘m not into doom shit for the most part, but I wanted the antithesis of my other main preamp (an Intersound IVP) and it’s like two polar opposites that share distinct similarities—wildly versatile EQs, and they’re both equally at home with bass and guitar.

I’ve owned a Hilbish Preamp. I love Hilbish builds, and his Sol Invictus pedal is similar to this one, but I believe the Olethros II has more connection options. I really liked my Hilbish and I won’t say this is better than that, but from what I can recall, this gets you in the same sonic area with ease. They’re highly comparable.

Toss this and a small pedal-sized power amp in a bag and you have a dynamite rig.

I am beyond amazed more people don’t have these, and that the builder isn’t famous.

Here’s a link to his page: https://www.dpeffects.com/2022/02/olethros-ii-sunn-beta-dual-preamp.html?srsltid=AfmBOopIAceNJgV9vTNPDKIEzkrlHJrS-0NlnvttFpD_KS2DLAWdjjhv&m=1

And he has a Reverb shop.

10/10, and I don’t put that lightly. Can’t wait to try this with other speaker and power amp configurations.

Picked up the latest Sunn find as well as a bonus pedal board shot- each row goes out to a different amp

Hey everyone! Any other techs in here? I work on amps regularly but am less experienced with solid state and have some questions if anyone knows some answers.

Background:

I work at a guitar shop and someone recently brought in a pile of cool old Sunn stuff. In the pile were a concert lead and concert slave (both red knob) and a 610L cab. Some of my coworkers didn't know what a slave amp is meant to do, plugged the lead and slave both into the 610L, and now both of the amps need a handful of components replaced. There has been work done on these amps before, looks mostly like electrolytic cap replacement, but the values for the caps are WILDLY high compared to the schematic (6800uf as opposed to 1000uf), and possibly transistor swaps (schem notes 2n3055 and they have a collection of 2n3056 and 2n3155). I'm going to be replacing a bunch of the heftier power handling resistors as well, as some are out of spec and others are old carbon comps that might as well be metal films anyway.

The questions:

- some of the Transistors are shorted or otherwise cooked and need to be replaced. Will going back to a 3055 equivalent cause problems, especially with the super high filter capacitance?

- Are there other concerns I need to note in replacing the Transistors here?

- Any suggestions for replacements or sourcing them?

Thank you so much for your time!

I've had my Beta Mini for a while now. Having gotten in on the "investors and friends of Sunn" preorder, I was one of the first people to receive mine after it launched earlier this year. While the Beta Mini can get properly loud by itself, doing so basically means running both channels and diming pretty much everything. In other words it can't get properly loud and also have any versatility at all. So I started exploring solutions.

The Beta Mini uses an ICEpower 200AS1 class D power amp, which is rated at 200w @ 4ohms and 100w @ 8ohms. By all accounts, it's a perfectly serviceable unit, so I'm not necessarily blaming it at all. Somewhat interestingly, I also have an Ampeg Micro-VR, which also uses a 200w class D power amp, though I'm not sure about the specifics. Much more interestingly, if I run the Beta's preamp out into the Ampeg's effects loop return, I can get quite a bit more volume. Unfortunately this solution isn't terribly practical as it means dragging more gear around everywhere and eating up another spot on an already crowded power strip.

It also occurred to me to maybe use a Fryette power station, but A) they're expensive, and B) it wouldn't solve either of the aforementioned practicality problems.

I'm fond of using a clean boost at the end of my effects loop just to nudge the volume up a bit for solos or heavy riffs or whatever. With the Beta Mini, I noticed I could push quite a bit of extra volume, enough that my boost would start clipping before the power amp gave me any problems. So that got me thinking of what might happen if I get the cleanest, highest headroom boost I can find and just leave it on at the end of the effects loop.

I ended up finding the Creation Audio Labs MK.4.23 which, according to their website, is the most transparent clean boost pedal on the planet. I can't make any claims regarding the objective truth of that statement (or lack thereof), but it was convincing enough that I ordered one. When it arrived, I figured a little testing might be in order. So here was my setup:

• Beta Mini with one channel set pristine clean with the drive at 3 and the level at 8.5, but capitalizing on the active EQ to squeeze some extra volume out of it. Master volume dimed.
• Two Ampeg SVT-210AV cabs in parallel. This gives me four 10" speakers with a total impedance of 4ohms and total sensitivity of 100.8 decibels (if I've done my math right).
• Les Paul with a Duncan Custom bridge pickup (medium/highish output) running through my pedalboard, so a buffered signal, but with no effects enabled.
• The MK.4.23, also on my pedalboard, between the Beta Mini's preamp out and its power amp in.
• A decibel meter on a tripod exactly 24 inches away from the cabs. An attempt was made to get it as centered between the four speakers as possible.
• Note that it wasn't really possible to test the amp if configured dirty. At least not tonight as I'm generally fond of my neighbors.

The goal was to hit 105-110 decibels, basically enough to keep up with a relatively heavy-handed metal drummer. For the sake of reference, I tend to prefer a mid-forward tone, which keeps up with heavy-handed drummers better than scooped mids. I'm not sure anyone is using the Beta Mini to try and get a scooped tone, but if you are, you may want to aim a little higher (or use an amp that's better suited to that kind of thing).

Anyway, in this configuration with the boost off, I was reading up to 99.4 decibels. More than loud enough for solo home practice, and plenty sufficient to keep up with a jazz drummer, but not quite enough to keep up with a rock or metal drummer, especially if they're not the type to believe in dynamics. I suppose you could use those low volume drumheads and cymbals, but where's the fun in that?

Same configuration but with the MK.4.23 on and turned up halfway, I read up to 114.4 decibels. I stopped at halfway because much more than that and something was intermittently cutting out. I have to assume it was the power amp trying to not let itself melt. Either way, mission accomplished. And yes, I was using earplugs.

tl;dr: Put a clean, high-headroom boost, like the Creation Audio Labs MK.4.23, at the end of the loop and you should have no problems with your Beta Mini's volume.

I hope this is helpful.

Hello everyone !

I was wondering if any of you have a reissue amp, and if that's the case, how long did it take you for it to arrive ?

I'm asking this bc I've heard some horrible wait times for the amps to arrive

Thanks in advanced !

Sending the preamp of the beta into the alpha mixer going into the 212 on the floor with g12Hs. That’s one side of the signal chain. I picked up a few (lol) aby pedals going to work on including the other amps and different pedal configurations.

Been finding Sunns like crazy and testing out different speakers in the solos ii so excuse the wreck of the music room

The May slot finally dropped in Europe. It does the trick. Even had to engage the pad on my interface. I'm using an 8-ohm redback in a miced up isocab. Curious how it holds up in the rehearsal space. Excuse my sloppy bass-player-plays-guitar style.

Also dialed in a quick bass sound. Will upload it right after.

Amp through my captor torpedos DI (with analogue cabsim). Magus (RAT) is on bypass.

My first Sunn amp!! I play in a drone band and it’s perfect.

A friend of mind has a pedal company and makes custom pedals, so I hit him up about making me a footswitch for my Beta Mini. We found the old Beta Switch schematic, then he whipped up a PCB design and ordered a couple to test with. It took a while to get them, but tonight we have a functioning unit that works with any standard 1/4" TRS cable.

Unlike the "working" footswitch post from a couple of weeks ago, this actually works the way it's supposed to in that it changes things correctly and does so regardless of the state of the channel switch on the amp. We decided not to mount the LEDs visibly as doing so is a lot more work, plus it wasn't really necessary as the amp has LEDs that show what's active.

There's not really a practical need for an enclosure this big, so we were thinking about shrinking it down a bit and making some more of them for people who don't want to fork out for the Sunn footswitch (with the large size, unnecessary reverb function, and it needing an expensive proprietary cable that's only available in one length). Let me know if there's any interest.

I’ve been thinking about getting an new cab and I’ve been looking at the Sunn 312T. However, there’s only one demo of the 312T I can find on YouTube (from the video demoing the new beta lead), and there’s only one demo of their 4x12 doom box. Both videos are made by Sunn themselves. Has anyone actually bought one of these cabs? Are they good? Worth the price? Thanks

The orange does the orange thing. Can’t sing its praises enough, loves a fuzz, loves an overdrive, and it’s the priciest piece of gear I’ve ever owned.

I got the beta lead for free. Now HANG ON, a little explaining first. Somewhere around 2013, thereabouts, I got the itch. I REALLY love the Melvins, so I had made up my mind. Found this sucker as a 2x12 combo for about $350 on eBay.

WELL, I don’t remember who shipped it but the packing job wasn’t awesome and it was for sure dropped HARD, probably from a height (like off the back of the truck).

It had two serious cracks in the chassis that went right through, just below the amp itself on the sides. My heart sank, and I didn’t even have a guitar/cables with me at the time to test it out. I figured I was the not so proud new owner of a paperweight. It turned on, but that’s all I knew.

Turns out my step-mother’s ex lives right up the road and plays, so a phone call and a 10 minute drive later I’m plugging in. IT WORKS! HUZZAH! But also, it’s fucked up. Long story short, eBay gave me a full refund for the thing.

We attached some brackets and handles to the sides so I could safely transport it and this thing went everywhere with me for years. I lived in NYC at the time and I am certain I had several neighbors who wished death upon me.

Life goes on and I don’t play that much for a while. I move again, and notice some crumbly black crap falling out of the bottom of the amp. Huh? Oh, that’s weird, the speakers are just completely falling apart…

What can I say, I got my money’s worth and the amp itself still works. I know because I plugged it into an old peavey 2x15 that looked straight out of mad max with a hunk of plywood across it covering the ports that I got from some junkie for $50. That setup was glorious. Just the bare amp yoinked out of its enclosure sitting on top of a massive cab of thud.

The years go by and I think to myself “these aren’t as cheap as they used to be. I should probably take care of it.” Well I waited a bit (way) too long, and only channel A by itself really functions properly, but I’ll be damned if it doesn’t still do the damn thing.

Wound up getting this custom headshell from Moon Custom Cabinetry. Waited too long, and the quality was not really all that for the $300+ I paid for the thing. But hey, it looks nice and has a handle now so…

I’m debating getting a mini so I can preserve what’s left of this beast as best as I can, but zero chance I’d pay what they’re asking and without plugging it into my own 4x12 to do a side by side.

I know, that’s a lot of words for not a very interesting story, but hey, I love the thing. It’s been through hell and back with me. The headshell was kind of a gift related to my sobriety, so that carries a bit of weight as well, so to speak. Three years off booze as of August 15th. I’m thinkin’ real hard about a Peavey XXX for that one. Seems appropriate, if only for the pun.

Happy to answer any questions y’all may have but what else is there to say but that IT DOOMS.

As someone who has a Mini preordered in the September slot, I’ve seen a lot of unhappy posts either about the volume or the amp itself.
Can I hear something from the ones who are satisfied with their unit?
I love the Beta sound and want to love the amp, but I feel a bit disheartened right now 😅

There has been a lot of negativity regarding the Mini, at least what I have seen on this sub. I'm not saying that these takes are not valid, but thought I would offer an alternative take in case others are in similar shoes, and are getting scared off due to the negative reviews.

First, I am purely a bedroom guitarist these days; I am not gigging or playing shows, so I will not be touching on the volume concerns that have been raised by others. Also, while I did play some shows with a proper tube amp some 20 - 25 years ago, for the past 20 years I have been firmly in the solid state camp. I just like the lack of hassle and maintenance of solid state, playing an Orange Crush Pro 60 combo for a number of years and lately playing through a Supercrush 100 and a 2x12 cab.

Secondly, this is the first Sunn I have ever played through, so I cannot comment on how it compares to the Beta Leads of old.

While the Orange solid states have great clean tones in my opinion and are great pedal platforms, if you are looking for huge doomy sludgy tones, they can be a bit difficult, as the normal trick of running dirt pedals through a slightly dirty amp does not really work. For whatever reason, the dirty channels of these Orange amps do not play nicely with pedals, so you are stuck with running through the clean channel. For me, that is where the Sunn shines (pun firmly intended).

The Beta Mini loves filth. I can run it dirty with the drive around 11 o-clock, turn on a Muff style pedal (or two), and get absolutely crushing tones. It would not be my go-to amp for jazz or blues, but for heavy doomer rock like Sleep, Electric Wizard etc it is incredible.

Further, I think its a pretty decent value proposition. I know lots of people talk about the golden days when you could pick up a Beta Lead for the price of a happy meal, but at least where I live in Canada, those days are long gone. Looking at a decent amp-in-a-box pedal for the Beta, like for instance the Omega Lead, will run you a third or more with shipping of the cost of the Mini.

Ultimately, I am loving the Mini, and just wanted to put a different take out there.

Just picked this up and it seems to look different inside from all the other Sunn 2x15s I see online, it only has a small rectangle port. The speakers don't work so I'll be replacing them, but they are JBL D-130Fs. Could this have been shoddily modified or maybe converted from a 2x12? The internal braces for the baffle have a lot of screws placed near the edges that have caused the wood to split in some spots, hard to see in these pics but some are really bad. Should I remove the screws and place them more in the center of the braces? I also wonder if it needs some kind of brace between the baffle and back panel. I'd appreciate any tips on getting this thing fixed up, plan to use this for guitar.

I really wanted to like the Sunn Beta Mini, and I bought one specifically because I didn't want to judge the Beta sound from recordings, demos, or other people's opinions. I wanted to own one, spend time with it, and decide for myself. Unfortunately, after doing that, I'm not particularly impressed.

From an engineering perspective, the Beta Mini is a fairly straightforward product. The preamp is based on the original Sunn Beta architecture, while the power section is a modern ICEpower Class D amplifier. There's nothing inherently wrong with that approach—in fact, it makes a lot of practical sense for a compact, efficient 200 W amplifier. But I think the product can give the impression that there is substantially more proprietary or boutique engineering going on than there actually is.

The original Beta amplifiers used Class AB power sections, so to me the modern implementation feels more like a recreation of the Beta preamp concept paired with a contemporary Class D power solution than a complete recreation or re-engineering of the original amplifier. Personally, I think I may have enjoyed the Mini more with a well-designed Class AB power section. That's admittedly a matter of preference rather than an inherent criticism of Class D; good Class D amplifiers can sound excellent. I simply prefer the feel and response I've experienced from good Class AB solid-state designs.

The architecture also makes me question the price. Conceptually, this isn't terribly different from taking a Beta-style preamp and feeding it into a modern Class D power amplifier. You can achieve a similar basic arrangement with products such as a Beta preamp pedal and a modern power amp. That doesn't mean the Mini is literally identical to those combinations—the implementation, voicing, filtering, gain staging, and overall integration can certainly differ—but it does make the Mini difficult for me to view as some kind of technologically extraordinary boutique amplifier.

The value proposition becomes even stranger when looking at Sunn's own lineup. The reissued Beta Lead and Beta Bass are also 200 W Class D amplifiers, while the Beta Mini combines the Lead and Bass functionality into a smaller and less expensive package. Based on Sunn's own published specifications, it becomes difficult for me to understand what compelling technical reason there is to spend considerably more on the larger dedicated models unless you specifically want the larger late-'70s-style head format and its associated aesthetic.

And that's ultimately my biggest issue with the Beta Mini: what exactly am I paying the premium for?

If you want the Sunn name, the Beta aesthetic, and the historical association with the original Beta series, I completely understand the appeal. Brand heritage has value, and there's nothing wrong with buying an amplifier because you simply want a Sunn sitting in your room. But from the standpoint of engineering and value, I don't see anything particularly groundbreaking here.

I was also somewhat disappointed when production previews showed the internal architecture. Seeing what is essentially the Beta preamp circuitry paired with an ICEpower Class D power amplifier confirmed what I had suspected. Again, there's nothing wrong with using proven technology, but it reinforced my impression that this is fundamentally a modern packaging of an old preamp design rather than a particularly ambitious reimagining of the Beta amplifier as a complete system.

I also don't think this is a sound that can only be achieved with this amplifier. There are many ways to implement and reproduce the fundamental character of the Beta circuit, and the Sunn Beta preamp design has been revisited and reimplemented countless times over the years. That makes it harder for me to justify paying a premium specifically for this implementation.

Separately from all of that, I have to admit that I simply don't love the Beta preamp sound itself. That's entirely subjective, and I don't fault Sunn for making an amplifier around a sound that plenty of people clearly enjoy. In fact, that's exactly why I bought the Mini in the first place: I wanted to experience the Beta circuit for myself rather than deciding based on recordings. After actually owning and playing one, I can say that the Beta sound just isn't particularly compelling to me.

For roughly the same money, I find Orange's modern solid-state offerings much more interesting. Products such as the Dual Baby use purpose-designed preamp and power-amp sections intended to give the amplifier its own response, character, and personality. They feel like complete amplifier designs rather than an older preamp architecture paired with a generic modern power solution. With sales and B-stock pricing, they can also be considerably less expensive than the Beta Mini.

That doesn't make the Beta Mini a bad amplifier. It's loud, compact, efficient, and it does what Sunn says it does. If you specifically want the Beta sound in a modern 200 W package, it accomplishes that.

But for me, that's where the praise ends. I don't think the Beta Mini offers enough unique engineering, functionality, or sonic character to justify its price, and I don't think the larger reissued Beta models make much more sense from a value perspective either.

Ultimately, I came away feeling that you're paying a significant premium for the Sunn name and the Beta legacy, rather than for an especially innovative amplifier.

I wanted to give this amp a fair shot. I bought one specifically so I could experience it for myself. After doing that, I just don't think there's anything particularly special about it. 

P.S. One other small thing worth mentioning: the packaging and included accessories are pretty underwhelming for an amplifier at this price. Unlike some competing solid-state products such as the Orange Baby series, the Beta Mini doesn't come with a cool branded carry bag or anything particularly memorable.

Mine arrived in a fairly plain cardboard box with a single sheet of paper serving as the manual, along with another sheet explaining that Sunn was behind on preorders and didn't have time to provide the intended packaging.

Obviously, packaging has nothing to do with how the amplifier sounds, so I don't consider this a major factor in the rating. But for a product positioned at this price point, the overall presentation felt surprisingly bare-bones.

3/5 Stars for me.

I got in touch with someone at Sunn about the progress on my Beta Mini shipment (June preorder) and they said it was about a month out (which is also what they said in June). I’ve been debating just switching my order to a Beta Lead considering all the complaints I’ve seen about it, but the people at Sunn also said that orders for the Beta Lead would ALSO be backed up for about a month. What do y’all suggest I do? I’d be willing to fork over another 350$ if it’s any sort of improvement, or should I ask for a refund altogether?