EC Aficionado (was: The Studio Jr.)

Understandable mate. I just figured while it was in the USA and with Craig might be a good chance for someone to grab it since Craig can swap voltage and do anything custom.
I'm probably making a mistake selling it but need funds for ATC upgrade.

 

My MTV G setup was "modestly" Soekris dac1541>Neurochrome HP-1>ZMF Verité C as I did not spend long enough at my desk to feel comfortable leaving a tube amp on constantly (not did I have the space, really). I had ordered an ecp DSHA-3F to replace the HP-1 in 2019, but it arrived with COVID, so it never performed at the office. Since WFH, with more space near my desk, tube amps are a lot more attractive, although the 3F also gets a lot of play. I don't have kids around (long grown & gone) but keeping outside sounds out means closed backs (the same ZMF VC).

 

5v4 has twice the drop as a 5ar4(gz34).

https://300guitars.com/articles/rectifier-tube-voltage-drop-chart/
The exact vdrop numbers won't apply to your amp, but the ratio between the vdrop does.

I noticed myself when I owned the Af, that it responds terribly to any hint of vdrop under what as 5a4r can deliver.
I've tested 5v4,5r4,5u4,5y3 myself with it. Nothing but a gz34 made it sound correct to me.

 

A minor note, but if you get a fat base tube, you will need a tube saver or you will need to cut the chassis hole a bit bigger. Got a fat base 5ar4 for my AF and found this out the hard way.

 

So Amp #1 sounded good with RCA/WE/RCA/Yggdrasil, and Amp #2 sounds fuzzy with Sovtek/WE/RCA/DAC1541, correct?

Seems to me that the first thing to do is swap the RCA rectifier into Amp #2 and see whether that fixes the problem. Because if it doesn't, then the issue is with either the rest of the amp or the DAC -- not the rectifier.

And if it does fix the problem, then leave the RCA in Amp #2 and try the Sovtek rectifier in Amp #1 -- maybe it'll sound fine there, and you won't have to spend any money. But even if Amp #1 doesn't sound great with the Sovtek tube, you'll only have to buy another RCA 5V4GA to fix it, and those don't cost much.

Also, if you have an oscilloscope, you can simply look at the power-supply output to see whether the rectifier tube might be causing problems. Unlike signal tubes, with rectifiers you can easily see whether the tube is performing well.

 

Thanks! I don't have an oscilloscope, so I have to go by ear. I think I'll have to do a careful tube rolling experiment. I've tried a few combos of all the tubes I have (2 rectifiers, 3 drivers, 3 power) but the total combinatorics are a bit daunting. Not to mention that the driver I'm using in #2, WE 396A, was not too happy on #1 with the RCA rectifier (hum) but it works perfectly on #2 (with Sovtek). OTOH, an Ericsson WE 396A works perfectly on #1. Oh, tubes...

 

Two Af questions:

1) Got a NOS Mullard 5AR4; sounds decent from the start, maybe a bit thin/muffled, but a bit curious about what to expect as it goes through its first 50 hours.
2) The power supply light on this Af seems to have died at some point during or just after its trip to me. The amp is otherwise fully functional. How tricky would it be to replace it?

Thanks!

 

2. You may know this already, but some of the (I think earlier) units had a very dim light. I thought the light on mine was broken when I first got it but after cupping it with my hand and peeking in, it was on. This was vs the newer units that I had previously seen which used a brighter light inside.

 

I'm pretty darn sure it's the first 25 amps that have the cooler old-school bulb. Should make it easy to tell which bulb you have, just look at the back of the amp.

 

Thanks, you are totally right, if I look straight at it with dim room lighting, I see the faint glow. I was looking from the side in normal lighting, which is why I was missing it.

 

#19. Reason I got confused is that I have a later Af at my other place, and the power light shows even in daylight.

 

Duh, thanks, I just realized I messed up my test. I was using different ZMF Verité closed, with different cable, than what I had been using (long story). I have the other cable with me, and when I switched the cables, thin it is not. The headphones are still different (different wood and pads) but closer to what I expected. Phew.

 

From ZMF OFC to ZMF Michanikos (silver). The latter is what I had been using for a long while with a different Verité closed pair. Maybe it's just a matter of auditory habit rather than a key difference.

I have Psvane ACME 2A3 on my other Af, RCA M-R black plates on this one. I like ACME better, everything seems a bit better defined and placed, as if a slight haze/smearing had been removed. I was contemplating getting ACME for this Af, but now I'm looking forward to your Linlai impressions.

 

I haven't yet seen anyone compare the Acme globes to the EML mesh yet. Anyone have insight on how they compare?