Mesa Boogie Strategy 500 Power Amp Retube Kits

The Mesa Boogie Strategy 500 Power Amps. Every kit is configured to provide a specific sound/experience.

All our Mesa Strategy 500 Power Amp Retube Kits include power tubes that are hand selected to run perfectly in Mesa amps. We have extensive hands-on experience measuring the fixed bias points in these amps and what grade of tubes will achieve optimal performance.

The default power tubes for these Retube Kits is a Matched octet of the JJ 6L6GC’s (installed in the outside four sockets on each side, see image below) and a Matched quad of the JJ 6550’s (installed in the middle four sockets). The 6L6GC tubes follow the classic sonic archetype with big lows, smooth mids and crystalline highs. What sets them apart is their low end clarity, mid-range detail and very clear highs without being overbearing or harsh. You can also use an octet of the JJ 5881’s. The JJ 5881’s are a Classic 23 watt 5881 in a traditional stubby bottle. “Jangle” for days and a very warm full tone. Right in-between the JJ 6L6GC and the JJ 6V6S in power. If you’re looking for that early-breakup “tweed” era character these are it. You can also use an octet of the JJ KT66’s in the outside four sockets on each side. The JJ KT66’s are one of our favorite tubes here at Eurotubes. These tubes have a clean low end response with a forward mid-range and articulate highs. When overdriven these tubes crunch up early in the upper mids and highs resulting in an incredibly complex tone that retains excellent low end clarity (just like the originals).

Options for use in the middle four sockets include a Matched quad of the JJ 6550’s by default, or a Matched quad of the JJ KT88’s. The JJ 6550’s are a high power tube with more headroom than your standard EL34 or 6L6 variant. Compared to the KT88, it breaks up a little earlier and has very raw and open overdriven sound. The JJ KT88’s are a replacement for all standard KT88 and most 6550 applications. These are a higher power tube with lots of headroom, thunderous lows and thick/aggressive mids.

The Standard Retube Kit is as close to OEM as possible. Maintaining the amps stock level of headroom and gain while providing a warm but even handed overall sound. The kit includes one Matched octet of JJ 6L6GC’s and a Matched quad of the JJ 6550’s by default and four Matched and Balanced JJ ECC83S’s.

The Gold Pin Retube Kit uses the JJ ECC83S Gold Pin variants to provide a smoother, creamier, and more singing overall sound. This option is less aggressive and has less “teeth” when driven hard. If you like a classic raunchy gritty overdriven tone, we recommend looking to the Standard or High Gain option. If sweet, open, and more refined is what you’re after this kit will do it. The kit includes one matched octet of JJ 6L6GC’s and a Matched quad of the JJ 6550’s by default and four Matched and Balanced JJ Gold Pin ECC83S’s.

Below is a visual guide showing all of the different combinations of Matched quads of tubes we have run in the Strategy 400.