Quote:


Hard (impossible?) to say without knowing exactly which which tubes you are looking to use, also note that not all changes are for the better . But I think in general different brands of the same power tube have less impact than preamp tubes but different types of power tubes can make a significant change. I also suggest you spend some time in the Racheal forum to check out other people's experience.

Personally I never loved those Tungsol EL34Bs... nice tubes but ultimately too concentrated and rigid for me. This may be different for you, everything effecting everything, and the Tungsols potentially being right for your sound, but my experience. I would probably play with both, knowing any tube change anywhere, as you have heard, will change the effects of the rest.

Also how would you like to change your sound? With all the power tubes you can use in the Rachel, you could do a lot with just them, changing the vibes faster or slower... more or less complex, lucid, dense, spacious, dynamic, delicate......

Though as Lon said, you can likely do a lot with 6SN7s too, I suspect you will end up playing with both. And however you start, buying particular tubes that might contribute to changes you are after is really important to me, never cut and dried, but perhaps getting you closer to what you love.

To help with that, we would need to know what you are using, and how you would like it to change...and even better, talking about what you have rejected and why.

For more speed and definition that is also pretty spacious and lively, having a good detail in space relationship, Gold Lion KT77s might be a good bet for shifting your amp in the direction you want. It has been a long time ago, but they did something special in the SE34 I had... a nicely balanced tube.... tight bass with exceptional dynamic contrasts and complexity throughout with good space and fine detail. I recall them as punchy, expressive tubes that were relatively open and fresh. In my tuned up/fast Torii, they were a bit much for me, but in my SE34, the dynamics and space were really nice, and I think lots of folks have liked them in Toriis.

Another thought would be exploring rectifiers in the Aric. Not sure how flexible it is, but 5U4GBs are pretty powerful and generally big and dense sounding across the spectrum. When the bass in the balance pushes too much, depending on room and all else, rather than getting stronger feeling, it can go too far into various degrees of muddle and masking, so feeling like less, when it is really more if the room and all else can't handle it. If this might be the case in your setup, changing to a milder, and/or faster rectifier could be worth exploring.

I am guessing you have the 5U4G-ST (coke bottle) or 274B that came with your amp? All sound different, but STs generally have a little less pushed sound than 5U4GBs, with luck, subtly leaning things down and increasing definition.

If the pre does not seem too dark/full overall, but needs to be faster/more defined, a GZ34 has a similar power feel to 5U4GBs, but could give a similar feel as the KT77s in your amp... more speed, dynamics, and definition with spaciousness and fine detail. Good NOS GZ34s are expensive though, and not sure if there are decent new ones. The last I tried was a Psvane with a brown base... seemingly based on some version of old Mullards or Philips GZ34s. It was OK here, but not great for me. I don't recall exactly why, the tube not being in long, but likely a little masked and slow, less nuances than nice NOS tubes. I wonder if Linlai is making a lower cost one... could be worth a look if this type seems worth trying with less risk than good NOS tubes.

Alternately, if your sound with 5U4G-STs is still a little thick/full/warm, then rather than GZ34, GZ32s are family in characteristic sound qualities, but less powerful, so more open, faster and lucid. There are variants, like 5V4Gs, Brimar a pretty nice one that is not as nuanced and complex as many variants of Euro GZ32s, but also can still be found relatively inexpensively, and pretty nice for a variation of these inherently faster, more open and dynamic tube types. The American ones are touch and go, the RCA STs usually warmer/fuller, so maybe not your thing, and the fat bottle GEs, Sylvania, and others tend to quite clean... often too clean for me in my setup, but they can be gotten pretty cheaply, and if you want to test a quite open and revealing rectifier in your pre, I think the Sylvanias I have with a horseshoes top getters are pretty nice tubes.

Other less pushed feeling, fastish and more open rectifiers are 5R4GYs and Type 80s with adapters, Globes in particular. The ST shaped type 80 tubes can be nice too, and perhaps more durable, but less nuanced and complex in general. I have enjoyed 5R4GYs and Type 80s with different tube setups, but it seems a number of folks had troubles with Type 80 globes with some of our Decware power supplies. I used them for a long time, and maybe I was lucky, also being pretty careful with choosing Ebay sellers, but I think only lost one over some years of using them a fair bit. I ended up finding the 80s a little too smooth in general, nicely so, but I wanted more complexity, and moved toward the RGN1064 (with adapters) and variants I have used predominantly for quite a few years now. As my stuff became faster with more easy-flow with power and signal, these resolving and less pushed tubes became just right for me... I might say sort of like a little less pushed and more resolving Euro GZ32s. These tubes are outside our 5V Spec, being 4V, but have a fairly high reservoir cap rating, and I have been using them for years here, only losing one that I can recall.

I find 6SN7s so variable, I can't really advise there. In my 300B/845 amp I have tried a number of 6SN7s as inputs, and lately was preferring Raytheon short bottles with side getters, a quite neutral and revealing tube with a small touch of warmth. But lately, after opening up the sound elsewhere, I am preferring the still revealing and pretty fast, but a little more round/warm sounding, round bottle Psvane CV181 SEs with grey carbon spray... the ones that came with my amp.

Anyway, a start for considerations maybe.