Kenwood KR-9400 Receiver

A Kenwood monster from 1976, the KR-9400 runs a 120 watts per channel and was one of Kenwood's top of the line receiver during the 1970's only to be superseded by the KR-9500 and the KR-9600.

This unit has a huge transformer with two 15,000uf power caps.

I look forward to auditioning this unit over the next few weeks.

Noresco NE 561 Speakers

A great find came my way in this pair of Noresco NE 561 speakers, these are Canadian made with a well revered Isophon PH2132E dual concentric Alnico 8"X12" woofer with a 3" tweeter center mounted.

This pair of speakers has a beautiful walnut veneer cabinet that was a little sun bleached but a few nice coats of Circa 1856 Naturoil brought out the best in the cabinets.

I have swapped to this oil versus Minwax as the Minwax off gasses for 48 hours and this product is all natural.

I opted to upgrade the internal speaker wire to 16 gauge and replace the tired caps with Solen Fast Caps and it has completely opened up these speakers.

It looks t me like Noresco built these speakers to Isophon specs according to the data sheet.

So how do they sound, absolutely amazing on the Single Ended tube amp. They need a little bump up in the bass region but the mid range imaging is incredible. The cone tweeter is nice and smooth without any paper harshness, almost horn like. The dual concentric driver really shines in placement of instruments and musicians, the sound from one origin source is a real joy to listen to, no wonder the Isophon PH2132 drivers are well sought after.

The efficiency is pretty high of at least 95db at one watt, which suits the tube amp perfectly.

I have become a real fan of well designed speakers that use natural roll offs and a single capacitor in the crossover, it means that the drivers were designed to work together and they are not off the shelf  drivers.

Speakers that do this the best are EPI 100's, AR 18B's these Isophon drivers, the Tannoy Oxford Gold's and the Sound Dynamic Concert 500's all have a 1st order crossover and they all sound best on a tube amp.

These Noresco'c image incredibly well as if they are a window into the music. If you are a tube aficionado these speakers should be on your list of must hear speakers. 

Paradigm Mini Monitor V1

Another and later version of the Paradigm 3SE Mini speakers that showed this past week is this pair of Paradigm Mini Monitors Version 1.

The Paradigm 3SE Mini's made it up to Mark 3 before being rebranded as the Paradigm Mini Monitor. A move to a polypropylene woofer was carried over from earlier versions of the 3SE mini but the Mini Monitor now has a titanium dome tweeter, replacing the Vifa fabric dome tweeter. the Mini Monitor is now sold in its' seventh generation.

I find the titanium dome to be smooth and crisp, revealing more detail in the music that the Vifa tweeter. The bottom end bass notes can be a bit boxy as the 6.5" woofer tries to fulfill its' duties. Where these little speaker really shine is from the lower mid range right to the highs, these are silky smooth with great depth of sound and really nice imaging.

To really balance out these speakers a sub woofer should probably be used with a crossover in the 100-120Hz range.

These speakers sounded nicer on a single ended tube amp versus the push pull tubes.

I have a feeling these speakers will be staying around for a while.

Paradigm 3SE Mini Speakers

Another pair of Paradigm 3SE Mini speakers came to visit me again. this is about the sixth pair of this wonderful speaker that has graced my aural pleasures.

This pair belongs to a friend of the blog and wanted to hear them on the tube amp. These are by far one of my favorite 6.5" 2 way speakers out there and well worth seeking out if in the market for a decent set of used speakers for a smaller space.

The sound way larger than they actually are and outside of being a bit bass shy they image great with spot on mids and highs.

I did do a quick re cap with a  4.7uf Solen polypropylene cap which improved the performance immediately. 

ADC 303AX Speakers

Acoustic Dynamics Corporation, ADC 303AX speakers came my way yesterday. This sealed 2-way speaker is right out of the early 70's and competed with the usual suspect including AR, KLH, Dynaco, Jensen and others.

 These speakers were built around CTS Alnico woofers and a CTS tweeter that also has a doped surround, before the infamous yellow phenolic ring tweeter.

The sound is very deep in the bass region smooth across the mid range and the highs were surprisingly crisp and clean with great dispersion.

Real walnut veneer cabinets are in good shape with all corners square, the usual Wabi Sabi* scratches are evident event after a light sanding and a coat on MinWax and I am fine with that. In fact I prefer Wabi Sabi to modern standards.

 These sound best through the Single Ended tube amp, in fact they sound fantastic, I am well surprised.

An old ad was found on the Audio Karma site from a discount store called Dixie's and you can see where they fell in the pack.

Generous gobs of the doping material have sufficiently cover the crossover that make the 6uf cap un accessible so I will just leave it as it is.

*Wabi Sabi: Japanese for the art of imperfection.



Broadly, wabi-sabi is everything that today’s sleek, mass-produced, technology-saturated culture isn’t. It’s flea markets, not shopping malls; aged wood, not swank floor coverings; one single morning glory, not a dozen red roses. Wabi-sabi understands the tender, raw beauty of a gray December landscape and the aching elegance of an abandoned building or shed. It celebrates cracks and crevices and rot and all the other marks that time and weather and use leave behind. To discover wabi-sabi is to see the singular beauty in something that may first look decrepit and ugly.

Wabi-sabi reminds us that we are all transient beings on this planet—that our bodies, as well as the material world around us, are in the process of returning to dust. Nature’s cycles of growth, decay, and erosion are embodied in frayed edges, rust, liver spots. Through wabi-sabi, we learn to embrace both the glory and the melancholy found in these marks of passing time.

Electrohome Kalmar 120 push/pull tube amp with Phase Linear Model 3300 pre amplifier

I have been lucky enough to be listening to a Electrohome Kalmar 120 push/pull slave tube amp connected to a wonderfully clean Phase Linear Model 3300 pre amplifier.

The Electrohome Kalmar 120 is probably rated around 25 watts per channel and does an incredible job at powering any of my speakers to their best.

The sound is deep and powerful in the bass region, coupled with an incredibly open and transparent mid range topped with silky smooth treble that is crisp and clean.

There is a huge difference between the sound of tubes versus the sound of solid state gear that when comparing A/B between the both I find myself returning to the tubes.

So far this amp/pre amp combo sounds best with the Tannoy Oxford Golds, then the NAD Model 30's, it makes my Mission 770 Freedom IV's really come alive and with a bit of equalization, powers the University RRL-12 to new heights. Not saying that this combo does not do any other speakers in my collection justice, I just find myself coming back to the speakers noted above.


How does a Single Ended tube amp compare to a Push/Pull?

To my ears the single ended tube amp is not a clear in the bass region but far more open and forward in the upper mid range/treble region. The push/pull has much more punch and control in the bass along with stronger lower mid range. The upper mid range is a little more laid back and the treble region is not quite as hot/sizzling.

Both are amps are a true window into music with proper and I mean in the room with the musicians sound, the imaging is transparent, clean and true.

Once bitten by the tub amp sound one has a hard time plugging the solid state back into the wall.

University RRL-12 Speakers

A friend of the blog arrived this week with a pair of immaculately refurbished pair of University RRL-12 speakers. The RRL-12 speakers feature 12" woofer with Alnico magnets along with a 5 inch midrange with Alnico magnets and a wonderful dome tweeter.

This pair of University RRL-12 were lovingly and painstakingly redone with mint cabinets and crossover that have high quality Erse and Solen capacitors along with audiophile grade resistors.

With a little tweaking with the brilliance control on the back along with a little added bass and treble powered through a push/pull Electrohome Kalmar 120 tube amp and these speakers sound absolutely fantastic.

Once the equalization was figured out the sound was very open and transparent with incredible detail and depth, by depth I mean the 3 dimensional image of where the instruments and vocals have their place in the room. It is as if you are in the same room as the musicians, the clarity can only be realized with a tube amp.

This surviving pair of University speakers are a real gem to grace this audiophile blogger.