I spent this evening playing through the Fliptop, P-15, and the Slampegg Twin using four of my basses (Rob Allen Deep 4 with the dual output - the main reason for the Twin, my 78 fretted P, my 72/78 maple fretless P, and the Blast Cult Gateway). I am going to wire up a pedalboard so I wanted to get settings for the various combos for my Two Notes Torpedo C.A.B. M+ and not have to worry about disassembling again.
I also put an older GE 12AX7 into the Twin.
Anyway, I'm not going to make this a long post because at some point I'll do a video or something because I have a LOT to say after about 4 - 5 hours of tinkering around. The three pres couldn't be more radically different even though they are all emulating essentially the same thing.
Side note: I'm really loving the C.A.B. M+. Dial in the pre tube correctly and use the right speaker and mic combo for your bass and it's surprising. Modeling has come a LONG way.
Slampegg Original (mini tube/6N21B) vs. Slampegg X
Both pedals sound really good. Kudos to Sushi. They're different so for me it depends what sound you're going for. The OG definitely cops more of the "classic" B-15 sound but with things like the Ultra High/Lo/Bright, it's more like a later model. Where you can tell the OG is more like an original is that it pairs better with the (not free) CTS IR from an older B-15 than the newer one they call WGrandBlvd (which I think is based on the modern Jensen).
Moving the gain just a little on the OG has a LOT of effect on the sound. Honestly I didn't really crank it past like 1 and I got the sound I was going for.
The X, as I expected, was tonally similar to the B-25B I used to have since it also used a 12AX7. There's much more headroom so the gain could go higher and more granular. It also sounded really good, but this time it sounded better with the WGrandBlvd IR. Again, the different voices as I kinda expected matched with a relatively equivalent "speaker".
What got me the most excited was when I used (not free) IR which Two Notes captured from the B-25B 2x15". I used to have it so I know it well. I played that for years. All I'm going to say is I now have a B-25B in a MUCH more portable rig. There's my rock tone, full stop. I'm so effing happy. Thanks, Sushi. That alone for me makes the X version worth it.
How well did it work with why I wanted the Twin? Fantastic. I could have the piezo and the mag plugged into different Slampeggs and tweak each sound. I know Sushi will never do a Twin again, but it's awesome.
Sushi vs. Broughton
All three handled both piezo (i.e. active) and magnetic (passive) pickups just fine whether the signal was hot or not. If anyone is concerned there, don't be.
Let me get this out of the way up front: the P-15 sounds freakin' incredible - and it should for the cost. Far and away it's the best of the three at
nearly everything. I can't run both outputs of the RA into it, so on that level it kinda sucks for the RA. I've been using my resistance mixer but I'd rather not deal with that. It does a really good rock tone with the 2x15, but the Slampegg X with the 12AX7 gives me more of that B-25B sound as it should due to the different tube.
The Fliptop is not bad. To me, it was the "worst" of the three. Even at 24V, I had a much harder time dialing in a sound. With the P-15 and both sides of the Twin that was never an issue. It reminds me more of a real, old school 60s B-15 in overall tonality with some of the quirks of it, too. If you want a sound more akin to a "classic" B-15, it cops it pretty well once I dialed in a sound. I don't regret getting it BUT if I let go of one, it'll be this.
The Fliptop will probably need some sort of clean boost because it's not loud at all. I bought a SV-Boost to put after it thinking it would work. It didn't. That I'm definitely going to sell. Boy people aren't kidding - that think even at 9V will blow your flippin' head off by just barely touching the knob.
If I was ranking, it's P-15 > Slampegg Twin > Fliptop.
What's right for you? It's going to depend on what sound you want. Best bang for the buck is the Slampegg IMO, and if you want more versatility in a pedal, the X is probably going to give it to you. The Classic is nice, but I think the X's tonal palate might be better for rock since it uses the 12AX7. Like I said, I got my B-25B sound pretty easily which I can't do on a real or "fake" B-15 with the other preamp style.
If I decide NOT to put the P-15 on the board, I could live with just schlepping the Slampegg and not think twice but ... P-15. Both will probably live on the board.
They're all pretty worthy and we're spoiled for choice. I've said it before: the Ampeg sound DNA is similar, but know which one you want. All B-15s are not the same, and a B-15 is not an SVT, V-4B, or B-25B, either.
I haven't compared any of these to my real B-15N yet and this is the first time I've really used any of them outside of the P-15 for any length of time.