Message started by kana813 on 07/11/11 at 19:26:01

Title: Rectifiers Tubes
Post by kana813 on 07/11/11 at 19:26:01

The TORII can use 5Y3GT, 5AR4 or 5U4 Rectifiers Tubes.

Which tube allows the TORII to output the most watts?

From what I've found, the 5Y3 is for equipment drawing 100-120 ma max, and 5U4 and 5AR4 are for current needs of 225-250 MA. The 5U4G is rated for less current draw vs. the 5U4GB.

The 5AR4 is a soft start and draws 1.9 amps vs the 5U4's 3 amps for fil.

For those of you that have switched from 5U4 or 5AR4 to 5U4GBs, have you felt the power transformers to see if they're running hotter?

Are there any other factors to consider?

Title: Re: Rectifiers Tubes
Post by will on 07/11/11 at 21:45:14

To me the main factors are sound, and I have not checked the transformer heat. But the sound indicates a progression from 5U4Gs doing the most (presumable current-wise too), 5AR4s in the middle, and 5Y3GTs the least, . They all work well in the Torii depending on what you want from them and the synergy with the rest….something I can't over-emphasize from my tube play. A not great sounding tube in one arrangement, can sound amazing in another. This is especially real with the Torii since it very transparent and revealing, has five tube sets, and some very useful switches and knobs to tune things with.

Like with VRs, the biggest general sound differences as you tone down the rectifiers are lighter/tighter bass, and an associated mild reduction in body and dynamics, and an opening/brightening in the midrange and highs. Pretty subtle and still totally dependent on the particular tube within the type, but these are generalizations I have noticed. I like things about all the types, but end up using 5U4Gs and 5AR4s most of the time.  

For me, the Bendix 5Y3GT sounds awesome, with great warmth, texture and detail, but I end up craving a bit more punch and power. 5AR4s seem perhaps faster than 5U4Gs in general and a bit tighter overall including a bit less deep bass. Perhaps as big a tendency is in the midrange, the 5U4G tending toward liquidity and the 5AR4 tending more toward detail and maybe texture. But this is hair splitting stuff and only my observation based on limited experimentation. I have two 5Y3GTs, three 5AR4s, and three 5U4Gs (two of which being I think 40s and 50s variations of RCA and all ST/coke bottle.)

The thing that can really be cool is using these different rectifiers to taylor your amp's signature, but also, the stock Rubys sound really good and Steve has arrived at a synergy with the stock stuff from his long experience and good ears. So I think this is a good start to get to know the amp. In fact, due to some other forum explorations, I reintroduced myself to the Ruby 5U4Gs, and thought they sounded really intensely in my face with the tubes I had in, and those amp settings. But now, after tuning the tubes/amp to them, I am enjoying them very much, and wondering what I found I did not like about them when I gave over to something else a long time ago. But I have more choices now with a lot of tubes to work with to get that magical synergy.

So it makes sense to me to get Steve's sound established in mind before playing around too much unless your tastes/system/ room won't let you do that.

Then, or after learning the designer's sense of the amp, the sky is the limit with tube play for this amp.

Title: Re: Rectifiers Tubes
Post by kana813 on 07/11/11 at 23:54:10


Thanks for your feedback.

I plan to listen to stock tube set before making any changes.

I haven't received my amp yet, but my main concern is will the TORII have enough power for my set up.

It's my understand that the 5U4G/B has a higher series resistance than the 5AR4, so the resultant rectified B+ voltage will be lower, and the amplifier's output power will be reduced.

I don't know how much of difference this makes in the TORII. If I'm close on the power issue, the 5AR4 might be a good move.

Title: Re: Rectifiers Tubes
Post by Lon on 07/12/11 at 00:03:54

My experience is similar to will's. You will want the 5AR4 if you need the grunt, but . . . you may not need it. These are pretty darned powerful amps. If your speaker doesn't need more, and the stock rectifier has the right tonal balance for you, you can play within that tube type for a while. . . .

Hope your wait for the Torii is short!

Title: Re: Rectifiers Tubes
Post by will on 07/12/11 at 00:24:28

Sorry, just crossed Lon's in the ethers, but here it is.

Kana, Sorry I have no technical knowledge in this. I will keep my ears open for more or less sense of power between the 5U4G and 5AR4 (I don't have any 5U4G-Bs). But my recollection says this will not make or break the amp for you. I don't think you will notice much difference in sense of usable power.....more in the sense of tonal values.

You will definitely get a big shift from input voltage from your source. So if your source is higher or lower than the typical 2v you will hear it. I use a Zstage (up to 5v) and that thing can seriously increase the volume.

I hope it works out for you, and I suspect the stock rectifiers are pretty optimal in balancing power and sound. Steve is THE font of information for this amp though and could answer your specific questions on Rectifiers as they relate to power in a heartbeat.

Title: Re: Rectifiers Tubes
Post by kana813 on 07/24/11 at 02:14:24

Anyone have a pair of 5AR4s they'd like to sell?

Forums » Powered by YaBB 2.2.2!
YaBB © 2000-2008. All Rights Reserved.