[tintinsnowydog]

Very cool! Battery bias it is then, keeps an electrolytic out of the signal path, should improve the sound. Most people do not realize it, but the last cap in the power supply is in the signal path in these single-ended amplifiers, so the BHC caps in this case. Another method to remove the cathode bypass cap, other than fixed bias is to use an active load, again like a CCS. The effect on the internal resistance leaving the cathode degenerated is minimized in this case, so you can get away with leaving it unbypassed. Can also take the signal output from the source of the bottom CCS FET, making the effect on the internal resistance irrelevant, although this technically puts a transistor "in the signal path", but for those that are not afraid of a little sand assistance, this can be very beneficial to the circuit especially if you have a difficult-to-drive output tube, like a 300B.

Lots of info to process here, thanks for sharing! Would be very interested to see your mods on the 336 or a 339 in the future

 

[hp4fun]

This is where you buy Cetron 7236. Grab while it last because I'm sure it will go fast after this.
https://tubeworldexpress.com/collections/power-tubes/7236

Fair price, and no need to gamble in ebay.

I got mine for $50. Used, though.

 

[UntilThen]

The final pub test... how will the La Figaro 339i drive my HiFiMan He1000se. To my astonishment, it drive this planar magnetics as well as my v280 ! I dare say I prefer LF339i over the v280 on Hekse.

Hekse is 35 ohms and 96 dB. LF339i handles anything from 32 to 600 ohms. Even the LCD-X at 20 ohms 95 dB sounds good on it. At no time did I feel this OTL amp is underperforming with Hekse compared to all my solid state amps and that includes Schiit Mjolnir 2, v280 and Questyle CMA 12.

 

[UntilThen]

Setup with what ever coffee table, piano chair and bathroom stool I can get hold of in the lounge, right next to my hifi gear and in aircon comfort because Sydney and the east coast of Australia is experiencing a heat wave this weekend.

This is how I will spend Australia Day, comparing 4 amps against La Figaro 339i with 3 headphones - He1000se, LCD-3f and LCD-X. The 4 amps are Questyle CMA Twelve, Schiit Mjolnir 2, Violectric v280, Woo Audio Wa22. There will be no favouring La Figaro 339i just because this is La Figaro thread. Opinions are my own and take it with a big bowl of salt.

Dac is provided by Questyle CMA Twelve AK4490 delta sigma chip set. Yggdrasil is AWOL.

 

[UntilThen]

2 other participants will join me today so it's more than one pair of ears trying out these combos. After an hour or so, it became very obvious that I prefer He1000se over LCD-3f and LCD-X. Not by a bit but by a lot. Whilst the Audeze(s) are good, it became increasingly clear that the He1000se is simply better. In the words of my Indian friend who came by the other night with ZMF Verite Close and HD800S, the He1000se is so much better. In resolution, staging and stereo separation. Even the bass to him, the He1000se is a clear winner. I'm in agreement with most of the points.

So I'll focus on just He1000se with these amps. This is where I have to smile big time after 2 hours or so last night. I'm far from finished yet with my evaluation but it is obvious that there are no poor sounding amps here and that make picking a favourite difficult. There is one amp that stood out though and I wouldn't announce it yet because I need more listening and scrutinising and I need my 2 assistant listeners to come in tomorrow for an unbiased combined view.

I've just roll in different power tubes on the amps now. Tung Sol 7236 on Wa22 and Tung Sol 5998 on LF339i. Mjolnir 2 still has the Amperex Orange Globe which I reckon is as good as mj2 could get. Others will disagree with me and that's ok because I don't have much tubes to roll in mj2 right now, aside from the Voskhod 6n23p '73.

 

[UntilThen]

I'm going to focus on Wa22 and LF339i for now. The 2 ss amps - Questyle CMA Twelve and v280 have a more spritely tone of their own. Snap of fingers are sharp and very distinct and every note is very clear and precise.The 2 tube amps (one OTL and the other transformer coupled) have heave and body to their presentations. Organic and texture laden is what comes to mind. The hybrid Mjolnir 2 sits somewhere in the middle.

 

[hp4fun]

I know it is a LF 339i thread, so this is a remotely related question: why no one bid on these Telefunken 6080 tubes? Seems still usable. From the images they look genuine to me.

https://www.ebay.com/itm/6-tubes-60...345217?hash=item3ff00d5501:g:NVEAAOSwpkpfyL0z

 

[UntilThen]

I wanted to buy the Telefunken 6080 from euroklang but he wouldn't send it to Australia.

 

[UntilThen]

Pictures or it didn't happen... It's very close between these 2 amps. Incredibly good sounding with these tubes in it. I have just a very slight preference on the La Figaro 339i. Just a little because the Wa22 with those tubes sound very good too, even though the drivers are the more common variety.

LF339i - RCA 5693 and Tung Sol 5998 ; Wa22 - Sylvania 6sn7gtb, Tung Sol 7236, Cossor 53ku.

 

[UntilThen]

Satisfaction overload. Mt. Sinai here I come. It's a surreal moment listening to 'Holding On' War On Drugs on Hekse with LF339i. I think these are made for rock and roll !

Ok I'll try a classical piece now. Piano Concerto No. 21 in C Major K 467. Sublime and soothing. LF339i is not all about head banging rock and roll. It's about refinement too.

 

[UntilThen]

Change of tempo now. Teresa Teng on Tian Mi Mi. https://tidal.com/browse/track/16331253
Vocals are lovely !

Now listen to Alan Taylor and Chris Jones on audiophile recordings. I have this on audiophile CD.

 

[hp4fun]

Change of tempo now. Teresa Teng on Tian Mi Mi. https://tidal.com/browse/track/16331253
Vocals are lovely !

Now listen to Alan Taylor and Chris Jones on audiophile recordings. I have this on audiophile CD.

Perfect for the Australian Day, mate!

 

[UntilThen]

Interesting experiment. LF339i as preamp out to Mjolnir 2. More tube tone now. MJ2 can not be accused of not enough tube tone now.

Noise floor is not audible with volume knob on MJ2 at 12 noon and that's loud. Next will try LF339i as preamp out to v280. I can only go via RCA preamp out to v280 or MJ2 RCA in.

 

[UntilThen]

LF339i as preamp out to v280 is a great tone. So much more body and heave now. Still details galore. I'm strictly using He1000se as my headphone now. I can't believe LF339i handles preamp duties so well.

Next I'll use LF339i as preamp to SMSL SP200. This is similar to @adeadcrab and @hp4fun using LF339i as preamp out to THX 789. So let's see....

 

[Bruc3]

I can't believe LF339i handles preamp duties so well.

How about pre-amp out to speakers?

Wonder if it gives speakers that extra organic sound.