Greetings friends, I hope you are well! 🙂

It's been a crazy time here at Jeff's Place with all the wildfires occurring in eastern Washington. The heat here is in the 90F-100F+ range, with little precipitation, making eastern Washington a tinderbox. 

Between lightening strikes and arsonists, we have had big wildfires in eastern Washington state that have been devastating cities nearby to me. Due to the severity of the fires the Governor has declared the wildfires an emergency situation in hopes of getting federal help. Thousands of people have been displaced and many homes burned down. 

We've had air quality alerts due to smoke from the fires with AQIs at 1000 and above, which is very high. Fortunately, here locally it has dropped down to  an AQI of 153, which is unhealthy, but we can still get out to shop for groceries, for example.  

I have been mostly staying inside, with my air filtration equipment keeping indoor air quality in good shape, and playing hifi and music games to avoid the smoke. That's what I do a lot for fun anyways, so all is good! 

The Duelund-Corona 832A Project

I've been doing quite a lot of listening to my bedroom system with my vintage Altec Corona 832A loudspeakers (see the Duelund-Corona 832A Project for more info).  I am blown away how good this system is performing.

It sounds so incredibly musical, the musical realism is amazing, the sound quality superb, and I feel edified every time it's playing music.

I've been using a cheap Sony Blu-ray BPD-BX650 player as a transport to feed my ancient Mhdt Labs Paradisea+ vacuum tube non-oversampling DAC.

If I remember correctly, when I bought the Sony it was $79 on Amazon. Now it has been replaced by the Sony BDP-S1700U, which is $114.

I connect the two with a homebrew shielded Duelund DCA16GA coaxial cable, and use a pair of Duelund DCA16GA interconnects between the DAC and the Leben CS300F integrated amplifier.  I connect the CS300F to the Corona 832A loudspeakers with Duelund DCA16GA tinned-copper speaker cables.

The Leben CS300F integrated amplifier has been a revelation after Frederik and I developed ultra-performing crossovers for the Coronas in The Duelund-Corona 832A Project - Serendipity to Ecstasy! article HERE. 

The Leben CS300F integrated amplifier is way better than I thought it was during my review of it, but the full musical magic it is capable of wasn't revealed until Frederik and I built the Duelund CAST copper crossovers for my Coronas.

The Leben CS300F integrated amplifier is good, really good!

I've got the loudspeakers setup in room boundary positions, which means room issues are essentially reduced to nil, and maximum living space is freed up.

Just as a reminder, you can't just setup any loudspeakers in room boundary positions, they really need to be designed for that, like Audio Note (UK) loudspeakers are, or like my vintage Altec Corona 832A loudspeakers were.

You might remember that Frederik and I chose to use the stock Altec N800E adjustable crossover circuit, but with Frederik's state-of-art Duelund CAST copper-foil paper-in-oil capacitors and inductors in the low and high-frequency crossover circuits.

The frosting on the cake was using Yazaki-san's recommended vintage Luxman AS-10 transformer-based constant impedance attenuators to provide high-frequency attenuation and adjustability instead of resistors, which makes it super easy to get the proper in-room tonal balance dialed in.

Just playing regular old Red Book CDs the performance of this system is astounding. If I blindfolded you, and I let you listen to it, then asked you what this system cost, my guess is you would say that it was at least $100K, and maybe more.

The cherry on top is that I can listen from essentially a position in the room and it still sounds great. 

Moral of the story: Don't let audiophile orthodoxy convince you there's only one way to do things. There's a few paths to musical bliss that don't cost a fortune. 

Audio Note (UK) Ongaku 211 Integrated Amplifier

The next audio system I'm going to describe actually does cost a fortune, and with an extraordinary level of performance that matches its lofty price point.  While the price tag will limit access to this level of system performance for many, if you can fit it into your budget it is an absolute mind blower. 

That would be my primary audio system with Tannoy Westminster Royal SEs with custom Duelund CAST crossovers using silver components in the high-frequency circuit, and copper components in the low-frequency circuit. 

What really blew my mind was the arrival of a full suite of Audio Note (UK) Level Five components to match with the West's.

The performance is so incredible that it really put me back on my heels. I've been struggling to articulate this level of performance, as words just don't seem to do it justice. 

The Audio Note (UK) Ongaku 211 SET integrated amplifier blew my mind with its Level Five performance level, and rewrote my perceptions of what was possible with audio amplifier performance.

I'm starting to recover from the shock and awe of encountering the Ongaku on my West's, and I've started writing the feature review of it. I just hope I can do it justice, as it is really something special. Wait for it, it is coming to Positive Feedback before too much longer.

Leben CS-60T Step-Up Transformer

I'm really digging the Leben CS-60T SUT.

I've got it in my office audio system paired with the Leben RS30EQ phono stage, and the pairing is superb. At the moment I've got the Triode Lab 45 EVO powering the Altecs in this system, but I want to try the Leben CS300F I'm using in the Corona 832A system with it, so I can give you an idea of what a full suite of Leben electronics is capable of. More to come about that. 

If you have a Leben based audio system the CS-60T SUT is a no-brainer.

Another no-brainer is pairing the Leben RS30EQ and CS-60T SUT with the superb Murasakino Musique Analogue ‘Sumile’ MC phonograph cartridge, that I have mounted on my vintage Thorens TD-124 turntable, that was restored and hot-rodded by Artisan Fidelity. 

Stay tuned for more on this!

Infineon's GaN Class D Amplifier

I'm intrigued by the advances being made with Infineon's GaN Class D technology developed by Jun-san at Infineon, and Professor Shibasaki's GaN amplifier presentation at the OTOTEN 2026 booth about it was a big hit, I have heard.

My first report about this exciting new technology was here: Exciting news: "... a landmark development in the century-long history of amplifiers."

Infineon's GaN Class D amplifier was compared to a 300B amplifier in the demonstration, and friends that attended were very impressed with the results.

As an update, I wanted to let you know that friend Yazaki-san forwarded me a couple video links about the demonstration that you can see below. They are in Japanese but you can follow along and get the gist of it.

First link: HERE

Second link: HERE

Yazaki-san is describing Infineon's GaN Class D amplifier technology as "... a landmark development in the century-long history of amplifiers."

Eventually I'll get a chance to listen to it, so I am looking forward to that. Of course I'll be telling you all about my impressions! 

Ok, that's all for now. As always, thanks for stopping by, and may the tone be with you!