The "Cascade"

The InVicta "Cascade" is built upon the 1953 Standel 25L15 circuitry, taken from the original hand drawn Bob Crooks schematics (which have been widely available on the internet for years). The Cascade, like the original 25L15, is a 25-watt, cathode-biased, point to point wired, true Class-A amplifier with one of the finest clean tones to be had.

The Cascade is housed in solid, finger jointed pine cabinet (21" H x 22 1/2" W 10 3/8" D), which are revered for their alive and acoustic properties. The handwired circuitry is built with the best components, and housed meticulously in a single chrome plated chassis. The result is a clear, linear sounding amp with volume, punch, and complex tones that accurately represent what you’ve heard on your favorite recordings.

The Cascade features two distinctly voiced channels, Normal and Bright (with notch filter), and four inputs (1. Hi and 2. Low). It features Treble and Bass controls, with an added Presence control – set flat, the controls allow gobs of bass and trebles. The Cascade has enough volume to fill a small-medium sized club and is perfect for rockabilly, jazz, country, clean blues, roots rock and finger picking. It also makes a great low volume steel guitar and bass guitar amp, not to mention a wonderful recording amp.

The Cascade is meticulously wired for low noise, low hum, and low interference. It comes standard with many top quality components, with upgrades available upon request.

• Sprague, Tube Amp Doctor and Illinois Caps


• Carling switches


• Switchcraft jacks


• Alpha Pots


• Mallory or Orange Drop Caps (oil in paper optional)


• Carbon Composition resistors (metal film on request)


• Professionally reconed JBL D-130 (Weber California optional)


• Electro-Harmonix Tubes (other brands, including NOS, optional)


• Heyboer transformers (made in USA) with Mercury Magnetics optional


• Solid core cloth wire

*** The buyer can select any color of knobs, cabinet coverings, grillcloth, transformers (EU 220/240 volt readily available), and even tubes (807's, EL84's, etc) and other components.

The Cascade is not an “homage” or an approximation of the 25L15 circuitry or sound – it is as close as possible to Bob Crooks’ original design and intentions. If you are searching for “that sound” and want an amp that many would consider more reliable, serviceable, more logically and neatly laid out, safer to operate, lighter to carry, and less expensive to own, then the Cascade may be for you.

While the cosmetics make no attempt to recreate the 25L15, the circuit is (at conservative estimate) 90% faithful to the original schematic – the notable changes being the removal of one of the chokes (unneeded with the quality of today’s filtering caps), the use of 6L6 instead of 807 tubes (read notes below), different output transformer design, and consolidation of power and pre-amps. In actuality, the circuit is virtually unchanged, and these alterations actually remove much of the dated features of the
25L15.

That said, if you want the look and sound of a genuine Standel 25L15, you’ll have find an original built by Bob Crooks and pony up about twelve grand for the honor. Or if you want the name, you can purchase a “reissue” from the company that bought the name. They make great amps and they are worth every penny. I highly recommend them.

Since the Cascade’s introduction a few years ago, it’s gone through a few refinements (thanks to Charlie Hall) and it is just a stellar sounding amp, if I do say so myself. Of course, some purists find it hard to swallow that the 25L15 design can or should fit into a traditional Fender style layout. Or that if anything is changed, it ceases to be “faithful” any longer. But we could cast that same sort of criticism at any sort of “reissue”. The changes I made could be seen as improvements, and also debunk a lot of the myths and secrecy about the 25L15. All in all, the 25L15 is a guitar amplifier – its functions are not mysterious, crazy, or so revolutionary that no one can understand it. It was, and is, a very simple and replicable design.

The Cascade has proven itself to even those who’ve heard originals and the reissues. It’s proven itself to those who are amp designers and have seen the original schematic and the Cascade schematic. And it will continue to prove itself. References are always available upon request.

My mission is not to talk anyone into buying something they don’t want, nor to (willingly or unwillingly) misrepresent anything I sell. I back up my products (I also am the owner and maker of O.C. Duff Pickups) and the Cascade began as a side project, with the intention of putting a few of them out into the world each year. Anyone who’s ever tested one in person has bought one – that is a simple and irrefutable fact.

807 vs. 6L6: there seem to be two camps on this. One being that, despite the fact that only a handful of the original 25L15’s used 807 tubes, that the 807 is an integral part of the sound. It’s a sweet looking tube, it’s unique and rare, it’s robust and sounds great.

The flip side is that, on paper, the 6L6 and 807 are virtually indistinguishable, the 807 having higher voltage rating (depending on the brand of the tube) and that the 6L6 was the accepted industry wide replacement for the 807, which would explain why no guitar amp company ever again used the 807. Having heard both the 807 and 6L6 in the amp,
I’ve heard a difference – but certainly no more than a 6L6 vs. a 6L6GC vs. a 5881 vs a 5881WXT, etc. To me, the 807 and 6L6 are in the same family, and both sound great. And if truth be told, based on first hand experience – I can say that I tried both, and I have a good ear, and the 807 is not worth the trouble, as far as I’m concerned.

The only reason to use the 807: ‘cause it’s cool, baby. It’s funky. Other than that, there’s a dozen good reasons to let them stay obsolete, the best being that the wiring of the 807 tube leaves exposed enough voltage to kill a person. But if that’s not enough, here are some other reasons:

1) The plate cap rattles at volume, making noise (which you can even hear on some recordings of Chet’s). It also will come loose at some point, requiring re-tensioning, etc.
2) 807’s are rare. NOS supplies are dwindling and expensive, and the only available current production are cheap and Chinese. And that goes for the caps and tube sockets too.
3) Expense: if you want 807’s, that means NOS tubes, sockets, and the fabrication of a metal enclosure around the tubes.
4) The Cascade is a working man’s amp. You can walk into any decent music store and buy an unmatched set of cheap 6L6 tubes, plug them right in, no biasing needed, and play your show that night.
5) Logic: if the 807 sounded that good, it would’ve been used in more amp designs, wouldn’t it have? It would’ve proved worth the trouble – but it never did.

That said, if you want 807 tubes – I’ll put them in there for you. Not a problem. But I present this information so you can make a factual decision.

All in all, the Cascade is a very, very close recreation of the original circuitry. It is a reputable, logical choice if you are searching for that elusive 25L15 tone. Please let me know if you have any comments or questions.


The "Cascade"
$1995.00