Looking for advice on EL84 based amps

[shaizada]

Hey Guys,

I came across a pair of Mullard EL84s from the good old days. I understand these tubes to be awesome and I think would be fun to listen to hooked up to my single driver crossover-less speakers. I'm looking for a EL84 based amp and was wondering if anyone has some nice recommendations?

Since I have a pair of EL84's, it would be best to suggest amps that use just 2, and not 4 el84's (I am guessing those amps would work in a push pull configuration). Amps can be integrated OR plain jane amps.

I see that the Almarro 205mkII is well regarded which sparked my interest. Any others that you guys like?

Thanks!

[Dusty Chalk]

Radii HAP-02 (I own)

ASL MG-Head + variants (many have owned)

...or you should just send them to me.

[shaizada]

OK, I picked up an Almarro 205a MKII brand new in black. Seems like it will do the magic.

I'm crazy buying an amp just to use my Mullard EL84 tubes. I hate to see them sitting there idle

[JimP]

pictures! what speakers are you running off the almarro?

[shaizada]

I'll have some pictures once I get the unit. It's supposed to ship on Monday

JimP....this should be pretty fun. I just realized that you have the EXACT same speakers that I have....the Omega Super 8 Alnico.

Great minds think alike buddy.

Since you already have this setup, tell me about the sound....how do you like it? Did you try any C1 cap rolling? I have an audience cap ready to go in once I get a grasp of the stock units sound signature.

Looking forward to your impressions.

[JimP]

Super 8 Alnicos - niice!!

I'm aware of the cap rolling, but I've kept my A205AmkII stock for now. My set-up is still suboptimal and listen fairly nearfield at low volume (primarily jazz, some foray into live dead, phish these days). The tone, especially midrange is sublime. Some minor quibbles with the amp, which are specific to my setup:

--unlike any of my other amps, the Almarro doesn't give me sufficient volume knob play (again, nearfield and low volume). My sources output too high voltage?? I stumbled on using a GS1 (now GS-X) as a preamp, which gives me more refined volume control at low volumes.

--I have a toddler in the house, I still have reservations of using an open tube amp. Ultimately when I set all this up in the living room, I'll probably go with the Leben, or the GS-X has opened up some ideas (as preamp to something like a Monarchy Audio SM-70 Pro or some Pass Labs variant).

--I may be wrong, but I have a hunch the Super 8 Alnicos could use some juice especially wrt the lower end. The Alnicos are 93db (which is lower than the original Superhemps).

--but for now, I'll still use the Almarro for the Super 8 Alnicos, and take my time with any adjustments to my system.

[shaizada]

Heya,

I also have dual deephemps to help with the lower end. I'm very excited about the Almarro just because I hear so much about this little amp.

Also, I'm guessing that in your setup, you now have 2 volume controls correct? One from the GSX and the other from the Almarro.

I'm doing near field listening as well, just because there is such amazing resolution and soundstage that it really connects me with the music being played. I love this perspective as opposed to the sit back and watch what is happening on stage (though that is also nice sometimes )

Tube rolling is what I am really wondering about. Tube rolling and capacitor rolling.

[JimP]

Also, I'm guessing that in your setup, you now have 2 volume controls correct?

yes, I set almarro volume fixed at 12 noon, then I can use preamp volume from 8 - 10 o'clock on knob.

try to contact Jon L, he seems to have a lot of experience with almarro tube rolling.

[Jon L]

try to contact Jon L, he seems to have a lot of experience with almarro tube rolling.

Jim, I can't believe you're still running stock Almarro

Both of you should at least replace the C1 (and I suggest 0.22 uF instead for mo better bass response) with these AmpOhm tin foil paper in oil. They are only like $15, and I prefer them now to the likes of Mundorf silver oil.

Ampohm Paper in Oil, Tin Foil Capacitors

As far as EL84, I honestly haven't run into any "bad" sounding EL84, but my faves include Ei, Sylvania, Siemens.

The 12AX7 position is very interesting. I used to use the likes of Sylvania triple mica 5751, RCA 5751, Amperex, and all kinds of exotics, but lately, the lowly(?) RCA 12AX7A/7025 and Raytheon 12AX7A/7025 have been doing some serious damage in my home, especially with speakers.

[guzziguy]

I like the sound of el84s. My speaker amp is the old Anthem Int-1. It uses 2 sets of quad el84 for the output. There is no bias adjustment so the quads must be matched. All these tubes produce a whopping 25 watts in a push-pull architecture.

[JimP]

Jim, I can't believe you're still running stock Almarro

I know, pretty lame on my part, as you've given me advice on this and tube rolling before. Some people have bypassed the volume pot on the A205AMKII (same issue of too much gain that I'm having) to use with preamp, maybe I can get someone out here locally to do this one-shot with the cap mod.

[shaizada]

I like the sound of el84s. My speaker amp is the old Anthem Int-1. It uses 2 sets of quad el84 for the output. There is no bias adjustment so the quads must be matched. All these tubes produce a whopping 25 watts in a push-pull architecture.

I love push pull topology as well. I also own a pair of Consonance Cyber 800 Monoblocks...78 watts push pull with a quad of EL34, pair of 6922 and a 5687 on each monoblock. Sounds unbelievable. Using some Svetlana Winged "C" EL34 right now from Upscale Audio, Amperex 7119 (5687 substitute) and Tungsram PC88 (6922 sub).

Sounds like love

[shaizada]

She came in today.....

and swept me off my feet! What a beautiful seductive sound that can stir your soul. Seems to be best with acoustic and small jazz ensembles so far. The intimacy is wonderful!

Using Mullard EL84 (much better sounding that the somewhat brittle stock tubes).

Driver is Amperex 7062 or Tungsram E80CC. Just fantastic! This is not just a good amp for the price, it is a great amp period.

[shaizada]

Jim, I can't believe you're still running stock Almarro

Both of you should at least replace the C1 (and I suggest 0.22 uF instead for mo better bass response) with these AmpOhm tin foil paper in oil. They are only like $15, and I prefer them now to the likes of Mundorf silver oil.

Ampohm Paper in Oil, Tin Foil Capacitors

As far as EL84, I honestly haven't run into any "bad" sounding EL84, but my faves include Ei, Sylvania, Siemens.

The 12AX7 position is very interesting. I used to use the likes of Sylvania triple mica 5751, RCA 5751, Amperex, and all kinds of exotics, but lately, the lowly(?) RCA 12AX7A/7025 and Raytheon 12AX7A/7025 have been doing some serious damage in my home, especially with speakers.

I'm confused about a few things. First, from audiocircle, Response Audio says the following:

1) If you are running smaller, full range drivers such as Omega speakers with the 5" or 6" driver and NOT using a sub, I would increase the size of the cap a bit.

2) If you are using speakers that already have a decent amount of extension down below or using a smaller speaker as mentioned above but also using a subwoofer, you can stick with the size that's currently in the amp. This will allow the amp to concentrate on the ciritical midrange more precisely.

I have always found that the best overall cap for the 205 MKII is the .068uF (it should have a .047uF in there now). This size seems to work best with a good majority of speakers.

So what is the proper capacitor value then? Do these guys mean .68 uF or 0.068 uF?

I have a pair of Omega Super 8 (Alnico Magnets) and a pair of deephemp subwoofers. I don't need more bass "quantity" but an improved bass "quality" and texture would be great.

Do you still recommend the 0.22uF (not a 0.022 uF right?) Ampohm Paper in Oil, Tin Foil Capacitors? If I need one or two of them depends on your reply to my questions. I just want to make sure I change the appropriate capacitor(s).

Also, from the circuit diagram, changing C1 means getting TWO capacitors (left and right) to solder in between the 12AX7 and the EL84 tube sockets. Am I correct? Just want to make sure.

Thanks!

[Jon L]

Yes, the stock value is 0.047 uF, and it's technically "sufficient" as far as bass extension in numbers. However, after trying a gazillion caps, I have found that even the caps of same uF value can have vastly different subjective bass response, which usually carries over into midrange and overall balance as well.

There are caps that are 0.047 that seems to have lower bass response and punch than 0.22, for example.

For speakers and headphones I have used (HE Audio, Senn HE60, K701, RS1, K1000, K340, Sextett), I have consistently found 0.22 to yield better satisfaction, not just in terms of bass extension/quantity but overall balance and richness of sound. 0.1 uF will do also.

For AmpOhm, 0.1 and 0.22 prices are similar, and yes you need two (one per channel)..

[shaizada]

ok...I'm going to order two Ampohm caps of 0.22uF, 630V values.

Thanks! I'll report back once I get a chance to hear them.

[JimP]

matt black looks good!

shaizada, if it's not a hassle, you mind snapping some photos of the steps of what you're doing? I know this is fairly straight forward, but I'm not that experienced, and the visual will help. don't worry, I won't hold you liable! want to try this when my work load settles down a bit.

[shaizada]

I'll take a few snaps for you...no problem

Seems like they got shipped the next day after I ordered. I'm waiting on them right now.

Honestly....looks like a VERY straightforward procedure. Just going to replace the stock coupling caps with the Ampohm ones....pictures will be forthcoming.

The Almarro sounds fantastic with the Super 8's. I absolutely love what it is doing and once a listening sessions starts, I don't really miss my monoblocks all that much. That is huge deal for me...as it just tells me how good this little Almarro is

But.....

once I switch back to the monoblocks....its game over. They really are much superior to the Almarro in ALL respects. Of course, they are tricked out to the 9's. Completely retubed to taste and (don't shoot me for this as it made a significant difference) I swapped in some Furutech rhodium plated fuses for an absolutely stunning effect. I couldn't imagine a silly little fuse having a significant impact on the sound of the monoblocks.

I ordered some Furutech fuses for the Almarro as well....let's see what happens there.

Its funny...I had a completely skeptic, non believer in tweeks audiophile buddy come over. I already told him that the resolution of the system is such that even a small change in power outlets would make quite a difference. I just switched the duplex receptacle from the Oyaide SWO-XXX to the regular one in the Exactpower EP15a that goes into the Almarro. Should have seen the expression on his face! Highs muffled in, soundstage narrowed, instruments blurred in with each other, bass became muddier....I could go on.

I went back to the regular configuration, and things went back to the high resolution sound he was originally hearing. Then we switched power cords (on Almarro) and fuses in the monoblocks (first both of them, then one in the left channel and Furutech in the right channel and it was a total mind fuck for him). He couldn't believe it like so many others. I just told him one thing...try things BEFORE you dismiss them. We think we know everything but we really don't.

Oh well...

I'll step out of the spot light now.

Will keep you posted.

~G

[shaizada]

Sorry for the delay in pictures )

These are pictures before the Ampohm caps came in. These show a 0.47uF Auricap in place. But I have the AmpOhm oil caps in there now, the 0.22uF value as suggested by Jon.

With no cap in place:

Right one in place:

Left one in place:

JimP, you gotta do the AmpOhm upgrade. What an amazingly warm and inviting sound without losing any details.

Anyhow, let me know if you have any other questions.

~G

[luvdunhill]

uh, why do you call this the "AmpOhm" upgrade?

[shaizada]

Read "Ampohm Capacitor Upgrade"

Ampohm is the name of the Capacitor manufacturer.

http://thetubestore.com/ampohmpiotin.html

I've been updating my resume with Microsoft SharePoint skills and I think that subconsciously trickled in when I was posting...hehe

Its "SharePoint" and not "Sharepoint".

[luvdunhill]

oh i see. I was confused when I saw Auricaps in there.... nevermind actually "reading" posts...

[JimP]

JimP, you gotta do the AmpOhm upgrade. What an amazingly warm and inviting sound without losing any details.

thanks for the clear photos, pretty much idiot-proofs it for me as to exactly where it goes.

Now do I unplug the amp while I solder these in, or not?.....[j/k ing]

[shaizada]

thanks for the clear photos, pretty much idiot-proofs it for me as to exactly where it goes.

Now do I unplug the amp while I solder these in, or not?.....[j/k ing]

You might get a different sound if you keep the amp plugged in while you're changing the caps.

Do report back and post your shockingly different findings

Tell me though, how does the Leben sound compare with the Almarro? I've been really thinking about the Leben CS300 but the Almarro is keeping me at bay for that low wattage goodness.

[JimP]

should be receiving the 0.22mF Ampohms (PIO tin foil) shortly.

shaizada, curious why you went with Auricaps (I guess different flavors)?

OK now for the NOOB QUESTION OF THE YEAR:

--the upgrade caps are to replace the stock coupling caps

--for the life of me staring at photo 1 vs photo 2, which stock cap was removed (it appears all in photo 1 remain and you put in the Auricaps...)

--photo 2 clearly shows where the new upgrade caps should go, so that's not the issue, but which one of the stock was removed?

Does that make sense?