Recto Preamp Tubes shootout

[Lasse Lammert]

just tested some different tubes for my RevF Recto..though you might be interested in the results.

here's a sheet showing the different combinations:

the files are 24bit

recto preamp tube test


(don't expect night and day differences)

 

[Mikaël-ange]

Haven't already listen but I just want to say... Lasse, V4 drive FX loop so put a sovtek or a shuguang (same recomandation for V5 tube since is used to be push pull stage). So I pretty sure that 1 and 2 sound the same since gain stage use the same tubes

 

[Lasse Lammert]

Haven't already listen but I just want to say... Lasse, V4 drive FX loop so put a sovtek or a shuguang (same recomandation for V5 tube since is used to be push pull stage). So I pretty sure that 1 and 2 sound the same since gain stage use the same tubes

Yup, I know....V5 is actually quite important for the sound, that's why I always have a balanced tube in the PI stage (both triodes symmetric)

 

[drew_drummer]

Not a massive difference, imo.

 

[rispsira]

didnt listen yet but awesome thread thanks Lasse

 

[John_C]

I'd say all tung sol is my favourite, but all china sounds a bit tighter and brighter which i like.
It seems the biggest determining factor is the inverter.

 

[Jevil]

Can't play 24 bits here aat the office... I'll comment when I get home.

Which is the function of every V in this preamp?

 

[Omega_Void]

Lasse, thanks for posting this.

I voted number 4, number 3 would be my second choice.

I was slightly surprised -- didn't expect much from the "Tung-Sol" based on my experience of Russian 12AX7 tubes. I guess I shouldn't tar them all with the same brush.

The chinese tubes OTOH don't sound half as lively in the recto as they do in my own amp. Due to the difference in the circuitry I guess.

...V4 drive FX loop...

Is V4 out of the signal path when fx loop is unused, then? V4a might simply feed to V4b if not interrupted by the loop, in which case the sound might still be affected by it.

I always have a balanced tube in the PI stage (both triodes symmetric)

That's important for hi-fi, but for a guitar amp a little imbalance here can add to the character -- less cancellation of the 2nd harmonics from the power tubes. I prefer that, but YMMV.

Thanks again

 

[Lasse Lammert]

That's important for hi-fi, but for a guitar amp a little imbalance here can add to the character -- less cancellation of the 2nd harmonics from the power tubes. I prefer that, but YMMV.

Thanks again

this is actually true. I just prefer a clean/neutral poweramp though.

 

[shogger]

For me it's 5. Most oomph while sounding defined and kinda more 3D than 1 and 2.
Overall great sound as always, Lasse.

Shogger

 

[Sacha]

Have you ever tried an RFT in V1? Pricey but they last longer then new production tubes usually and I think they sound a bit better.

 

[sprack]

I honestly cannot hear a difference between any of them. Even the waveforms look almost identical.

 

[ahjteam]

I honestly cannot hear a difference between any of them. Even the waveforms look almost identical.

did you try with headphones?

 

[sprack]

Was running it through my ASP8's. I'll try the 7506's and HD280's to see if there's something discernible.

EDIT: I can't hear any difference through the headphones either.

 

[Mikaël-ange]

Is V4 out of the signal path when fx loop is unused, then? V4a might simply feed to V4b if not interrupted by the loop, in which case the sound might still be affected by it.

According from Mesa manual answer is yes

@Lasse: here my verdict
1&2 sound really close but (as espected) but 2 have more lowend than 1. So V5 have an influence on soundlol:
I prefer 2 to 1 personnatly.

My taste are:
5/4/2/3 (and I put 1 out since I prefer 2 to 1)

Thanks for take time to do this btw

Mikaël-Ange

 

[Lasse Lammert]

According from Mesa manual answer is yes

@Lasse: here my verdict
1&2 sound really close but (as espected) but 2 have more lowend than 1. So V5 have an influence on soundlol:
I prefer 2 to 1 personnatly.

My taste are:
5/4/2/3 (and I put 1 out since I prefer 2 to 1)

Thanks for take time to do this btw

Mikaël-Ange

wow, three is actually my favorit...I was not sure if 3 or 5, but 3 seems to be thicker and more organic, yet tighter than 1,2,4.
3 wins for me

 

[Mikaël-ange]

Different choice for different taste

 

[kev]

Thanks for the test Lasse. I'd be lying if I could hear a difference, though. 3 seems to have a wee bit more prescence, but that could just be a mind trick now lol. It definitely has something the others dont very slightly. The slightest nudge on any eq pot on the amp would completely override it lmao. I thought tubes would really makd more of a difference than that, so thanks for demoing that. Im now a complete unbeliever in the differences in tubes other their build qualities.