Resurrected 1993 B&K Components ST1400 Power Amplifier deserves WBC Ultimate 8 Gauge Speaker Cables

April 7, 2025

#510

Gentle reader,

I know, I just wrote to you about being able to get my wounded 1993 B&K Components ST1400 Power Amplifier working again: The Robb Collections: Wounded B&K Components ST1400 Power Amplifier is Back from the Dead! Dynaco A25XL Speakers Driven.

Above, is the "before" photo.

In my defense, I had, out of desperation, yanked the amp out of the system and I thought, "Is it time to buy a NEW power amplifier?" The Robb Collections: Review of Marantz MM7025, their Last Two Channel Power Amplifier.

Not being one to let a wounded comrade die from what might be a minor wound, I decided to see if I I could determine what the problem was without the nonexistent factory service manual or even a schematic.

Since the amp was working fine now, I decided to do what some folks do: Place the power amp near the speakers. With the last of my pink Monster Cable speaker wires attaching the amp to the too-long-dormant 1974 Dynaco A25XL speakers and the music was sounding great, I decided to go ahead and buy a pair of short WBC speaker cables.

Above is how they arrived from Amazon.
As I discovered with the new Marantz 7025 power amp and wanting to use my Dynaco QD2 unit and vintage Realistic APM-300 LED power meter between the B&K PRO10 preamp and the 7025 power amp was by buying Center Channel speaker cables:

There were many lengths to choose from but none were bargain prices. The white-clad ones above are 7 gauge, their largest and thickest wire. I picked two:

"WORLDS BEST CABLES 5 Foot Ultimate - 8 AWG - Ultra-Pure OFC - Premium Audiophile HiFi Single Speaker Cable for Center Channel with Eminence Gold Banana Plugs & Carbon Tweed Jacket."

Unlike all of the previous WBC (XLR, RCA and Speaker) cables which were all made in Japan, these were made in Taiwan. Now, I have no problem with products made in Taiwan. It is a free democratic country and the few things I have bought which were made there are well made and, so far, trouble free.

Should I play some striptease music?

Their boxes are so well made, I am keeping them. One never knows when one could need a nice, sturdy box or two.

A bit like jewelry, what with the silk bags protecting the terminals and the cables tied with silk ribbons.

I had routed the pink Monster Cable speaker wires underneath the base of the bamboo-stools-made-speaker-stands and up to the speaker's terminals.

Image above courtesy of Canuck Audio Mart.

The flexibility of the pink wires made close placement to the record shelf possible.

The RCA cables are "WBC 10 foot RCA Cable Pair - Gotham GAC-4/1 Star-Quad Interconnect Cable with Amphenol ACPL Black Chrome Body, Gold Plated RCA Connectors - Directional."

No fair comparison in size when they are woven cloth wound.

Monster Cable XPHP 2 Conductor Advanced Speaker Wire:

Key features Monster Cable features are:

Magnetic Flux Tube (How a clear hollow plastic tube can be "magnetic", I do not know.)
Time Correct Windings (A term Monster Cable came up with for the different gauge conductors in each wire.)
Linear Polyethylene Dielectric
Flexible Jacket

WBC states that the cables I bought are 8 gauge which makes them slightly smaller than the 7 gauge shown below. But significantly larger than 12 gauge.

These two images are official Worlds Best Cables advertising images, via Amazon.com.

Before Picture above.

"After Picture" above shows how much thicker and less flexible (due to cloth sleeving) is, which required me to move it further away from the record shelf. I rerouted the new speaker cables and RCA cables so that they are all further away from the shielded Belden power cable. Plus, it looks much neater.

The Belden power cable is away from and at a right angle to the other cables. Even though it IS shielded, it is "best practices" to do this type of cable routing.

Left speaker's cable routing.

Pink wires nestled in the WBC boxes.

1993 B&K Components ST1400 Power Amplifier powered up and playing Thin Lizzy's first album to start "breaking in" the cables. Cowboy Song is THE ultimate Rock Guitar song, in my opinion.

Most early Dynaco Speakers came with beige grille cloths. These $99 eBay finds had this black cloth which seems to be from the factory.

And, the finally, the "money shot" showing the completed installation of the revived power amp using WBC large gauge speaker cables like the rest of the system is equipped.

I hope that I am now done having to put money into the system for a while. I had been SO happy with it for many years right up to the 1990's Panor-era Dynaco ST-200 power amplifier losing it's left channel. Again, NO service manuals or schematics for their equipment. That started a landslide of spending which I have been documenting for you.

Thank you SO much for reading my article! Sometimes I get a bit verbose, but so many of you are reading my articles (more than half a million of you! I still can't believe it) I cannot thank you enough.

Feel free to comment below or on Facebook. Also, note that EVERY previous article (more than 500 of them) are right below this one.

Scott Robb

April 7, 2025

#510

Wounded B&K Components ST1400 Power Amplifier is Back from the Dead! Dynaco A25XL Speakers Driven.

April 3, 2025

#509

Gentle reader,

I've been enjoying the hobby of home entertainment in the form of listening to recorded music with the most realism my budget can afford since 1976.

This image shows the 1970's Dynaco A25XL speakers I scored via eBay years ago for only $99. In front of them is my once electronically wounded B&K Components ST1400 stereo power amplifier. How I came to own one of the now-out-of-business American audio companies fine pieces of equipment can be read here: The Robb Collections: 30-year-old Panor-era Dynaco ST-200 Power Amp loses Left Channel. Meet the B&K Components ST1400 Replacement Amp!

This image shows it installed into my system prior to my going crazy buying replacements for ALL of my wiring with WBC (Worlds Best Cables) cables.

Matching pre and power amp side by side. The WBC XLR cables I bought were too short to reach the power amplifier if it was all the way to the left. MY OCD really did not like that!

You too may have suffered from this type of logic: "Well, I really like this __________, so, I might as well buy the matching_____________________." Which I did by buying the matching B&K Components PRO10 preamplifier which has an external power supply made of Unobtanium. "Why is that the case?" you may be thinking.

My theory is this: Some of percentage of what is sold via eBay are things which the seller's parents once owned. There were three PRO10 units on eBay when I went looking. Only this one included the power supply. The likely scenario is: said adult children of late-parents carted all the stuff they wanted from Mom/Dad's house to a storage locker having decided to see what they could get some money out of by putting things on eBay, Facebook Marketplace, or wherever. By the time they got to their Dad's stereo stuff, they had no idea what this unmarked little metal box with a cable coming out of it was for. They put the preamp up for sale to those looking for a PRO10. I myself, did not know the situation separate power supply situation, but the seller of the one I bought said in the description: "..WITH power supply." That's what this article is about. The Robb Collections: Panor-era Dynaco PAT-6 in Reserve, Made-in-the-USA B&K Components: PRO10 Sonata Preamplifier and ST1400 Power Amplifier

So, everything is going along swimmingly as far as wonderful sounding music and I was proud that B&K Components were designed and built right here in the US. The trouble is, they are also from the 1990's as are the Panor-era Dynaco PAT-6 Preamp/tuner and ST-200 power amplifier were. One day, the left channel was very low volume and crackly!

Like the late 1990's Dynaco, B&K Components went out of business a few years ago and they shut down their website too. I could find ZERO service information on their products.

I worked on things with electronics for a little longer than I have been in this hobby, starting in 1973 as a new-car dealership auto mechanic for nine years, switching in 1982 to working on the nation's capitol's Subway cars for an additional 35 years, then retiring. So, I know much about electronics, but without a schematic, I don't know where to look for the problem with an ohm meter.

Fellow vintage electronics lovers are always talking about "recapping" their receivers and amplifiers. So, I took the amp far enough apart to be able to read the information on the four large power capacitors. I found exact ((looking) replacements and bought two.

Once the board which attaches to the two large capacitors was out of the way, I decided to remove the amplifier board and heat sink to take a closer look. That is when I spied the four glass BUSS AGC 4 amp fuses. B&K had wrapped a thin yellow piece of tape around each, perhaps to make them more visible. I began to look closely with a LED flashlight. That is when I saw one fuse had "blown". "Ah-hah!", I said. I looked through my supply of glass fuses and had five 3 amp ones and one 5 amp. Fuses open (and circuit breakers too) because there is a problem somewhere. Putting a larger (higher capacity) fuse in to replace an open one is a BAD and potentially dangerous idea. DO NOT DO THAT!

Since I had already bought and installed a new Marantz power amplifier. The Robb Collections: Review of Marantz MM7025, their Last Two Channel Power Amplifier. I thought, "I have nothing to lose, it's already broken, try the 5 amp fuse."

Some time ago, a fellow reader of this blog, and now my actual friend, Bob Berne, had sent another fellow reader, and also now actual friend, Bruce Woodrow and myself a kit to build a tiny Chinese tube buffer amplifier. After messing with those for a while, I bought two other Chinese, but factory built and better quality, tube preamplifiers to see if it would make an audible improvement in my systems.

Using my SONY CAR Discman as a source and the last of my Monster Cables pink speaker wire driving my 1970's Dynaco A25XL speakers, I fired everything up and waited....perfect sound!!!

I was SO happy! I went on eBay to find genuine BUSS 4 amp AGC fuses and ordered ten of them. Once they arrived, I replace all four 32-year-old fuses with new ones. I put the cover back on and retested it. Still perfect.

Since my also now-one-channel (and now residing in Bob Berne's Dynaco Museum) Dynaco ST-200 power amplifier had TWO sets of outputs and the B&K Components and Marantz MM7025 only have ONE set of speaker outputs, I have not been able to enjoy my 1970's Dynaco A25XL speakers. FYI: They are 3dB more efficient than the standard A25 speakers, and thus take half the power to produce the same level of sound.

The thick power cable (shown) I am using for the ST1400 is from a dead PURE|AV power conditioner. It is made by Belkin from their famous 19364 shielded power cable. In the past, I had replaced factory power cords with this cable on many power amps and receivers.

When something electronic dies, I disassemble it putting the PC components and transformers in a box for transporting to the county's Hazmat/Electronics recycler facility. I recycle the metal parts as well. If it was driven by a "wall wart" power supply, I keep it, just in case... Sadly they only accept #1 and #2 plastics for recycling.

I decided to use the now-revived ST1400 power amplifier to drive them.

See the matching stands under the Dynaco A25XL speakers? I came up with an inexpensive alternative to factory-built speakers stands. Many of which are made from inferior particle board or MDF covered in black vinyl or paper: Bamboo stools. The Robb Collections: Wooden Speaker Stands and Risers too Expensive? Try Bamboo Stools. How-To Guide. I first found a perfect pair which matched and replaced the falling apart bases from my Klipsch KG4 speakers. They too perfectly matched. The secret to keep the stands firmly attached to the speakers is revealed in the article linked above.

The system in 2018. Klipsch KG4 on the left with bamboo stool for a stand.

The B&K Components PRO10 preamplifier has THREE stereo outputs (below). Two sets of RCA terminals and one pair of balanced XLR outputs.

So, now I have the ability to listen to the Cerwin-Vega! LS-12 speakers driven by the Marantz MM7025 in stereo, or in pseudo-quadraphonic with my Dynaco QD-2 supplying the pair of Tannoy C-88 tower speakers behind my listening chair with ambiance and sometimes individual instrument sounds.

It does a marvelous job of making me feel like I am on stage with the band or orchestra. Truly a marvelous passive device. Unlike it's QD-1 brethren, it has three-way binding/banana terminals on the back rather than the cheap spring terminals.

And, if I really want to be blasted, I can once again drive all six speakers at the same time, but now with two separate power amplifiers.

And that, my dear readers, is the end of this saga. I am SO glad that I took the time to try and figure out why the left channel of the ST1400 was failing. There are four fuses, two for each channel. I do not know enough about complex electronics to understand why any sound was being produced in one channel with an open fuse, nor do I care. I am just VERY happy that it is fixed and all is well in my audio world.

Thank you SO much for taking the time to read my humble blog. I began writing many years ago just for something to do. Little did I know that so many people would be interested in what I have to say! Feel free to comment below or via Facebook.

Also, every (all 508!) article is below this one, at least on a PC it is. Happy listening!

Scott Robb

April 3, 2025

#509

Is Physical Media-Based Home Stereo (Two-Channel) Music Listening Going Away? Or Have Streaming, Smart Phones and Ear Buds Taken Over?

March 13, 2025

#208

Gentle reader,

My previous article dealt with my needing a replacement stereo power amplifier after my second 1990's unit also developed a problem. Here is the link to it: The Robb Collections: Review of Marantz MM7025, their Last Two Channel Power Amplifier.

In that search, I found a real lack of two channel equipment except budget priced stereo receivers and some stereo integrated amplifiers. I mentioned this and as a result, I began a more in depth look at what NEW audio equipment was available locally, i.e., Best Buy, (not much) or via a popular audio/video website which happens to be in Virginia, which is where I have lived for almost fifty-one years now. That site being: Crutchfield: Car Stereo and Audio, Speakers, Home Theater, Pro Audio, TVs

Image by and courtesy of Crutchfield Audio

I exhaustively searched their entire website and compiled lists of what they carry to determine if multi-channel audio/video (Home Theater) equipment was proportionally more of their items offered for sale, or was two-channel (Stereo) dominant?

Crutchfield

Stereo Receivers: Choices 20

Cambridge Audio 2

Denon 2

Integra 1

Marantz 2

McIntosh 1

Onkyo 1

Sony 1

Yamaha 10

Total 20

Stereo Preamps 32

Anthem 2

Cambridge Audio 3

ELAC 1

HiFi Rose 6

iFi Audio 3

Marantz 2

Mark Levinson 1

McIntosh 2

NAD 2

OSD Audio 1

Panasonic 2

Pro-Ject 2

Rotel 4

TEAC 1

Total 32

Stereo Power Amps 18

18 of 112 Power Amplifiers available are two-channel/stereo

Stereo Integrated Amplifiers 34

124 items listed. Many are Streaming Amplifiers

34 are JUST Stereo Integrated Amplifiers

TOTAL @ Crutchfield 104

Home Theater Products at Crutchfield

Multichannel receivers 62

Surround Sound Processor Preamplifiers 8

Multi-room power amplifiers 44

Multichannel power amplifiers 94

Multichannel integrated amplifiers 90

TOTAL 298

In answer to my question above: "(Is) multi-channel audio/video (Home Theater) equipment was proportionally more of their items offered for sale, or was two-channel (Stereo) dominant?" That answer is yes: Home Theater equipment is FAR more of what Crutchfield carries over Stereo equipment. Is this the national norm? Worldwide? I have no way of knowing. But, I suspect it is typical of most countries.

These statistics compiled above are based solely upon my spending a long time on Crutchfield's website. Which is something I recommend you do if you are looking for something new.

I bought a new Yamaha integrated amplifier, like this one, to replace the aged one seen in the image below, which was the Yamaha stack I had created to supply music to my Klipsch KG4 and BOSE 301 speakers in this room which we designated "The Office" before we moved in twenty-four years ago.

This is from 2019. Only the cassette deck remains and it is not in the stack anymore. Every other component has been replaced do to failure or my finding something better, such as an HD Radio tuner. So, like Grampa's old Ax*, while A stack of components still sits there, none of it is the same.

*The story of Grampa's Old Ax goes like this: "This is Grampa's old ax. The handle has been replaced three times and the head once, but it's still Grampa's old ax." Of course nothing remained of the ax. Both parts were discarded. Therefore, it is not Grampa's old ax.

That so many stereo components (104) ARE available as new at Crutchfield, makes me wonder if my question is answered universally. If I were to type "Stereo Amplifier" into Amazon's search page, there would be MANY items listed. How many are NOT made in China? How many are what the typical home stereo enthusiast would buy and enjoy at home and be proud to share and show off to others? Compared to how many are capable of reproducing recorded sound and not, in your opinion worth even thinking about?

Parts Express: Speakers, Amplifiers, Audio Parts and Solutions is a site I have visited often in the past when I was modifying old speakers, such as these below. They carry all kinds of electronic stuff and are kind of the 21st Century's Radio Shack.

Above, a modified Radio Shack LX5 speaker.

I found this pair of LYRIC speakers with ten inch woofers at Salvation Army many years ago. The surrounds were completely gone. Stock speaker on the right with new Eosone woofer already installed. ALL Eosone drivers with Cerwin-Vega! E-310 crossovers.

This is a Realistic Minimus 11 metal speaker. All components replaced.

My famous Radio Shack Minimus 7W speaker (one of two) on the left and one of two stock ones I also bought on the right. The Robb Collections: Converted my already upgraded Minimus 7 speakers to ribbon tweeters!

Modified Minimus 11 compared to modified Minimus 7W.

I did this search on their site just now: Search results for "stereo amplifier" and it yields 113 results over five pages. Many are their own brand "Dayton Audio". Others, like PYLE brand are ones I would never buy. When I searched for "Class D" it yielded 135 results over six pages. Many are built PCBs which one needs a power supply and a cabinet or case for. Others are "Audio Excitor" drivers, and subwoofer plate amplifiers as well as car audio amplifiers and mixing consoles with a few subwoofers. They have ONE name brand stereo integrated amplifier, a Denon model, in all those pages.

I feel that it is safe for me to say that if one were to walk into the average (not high end) electronics store what they would likely find was all kinds of HDTVs home theater receivers, Blu-ray players, subwoofers and multiple speakers of all kinds and sizes to enjoy the sound effects in their home of a Blu-ray or DVD being played and/or being steamed. But, stereo equipment, if they carry it at all, might be over in a corner somewhere with just a few components to choose from. That is IF you have any home entertainment electronics store near your home. We have one: Best Buy.

To conclude: If I had access to sales figures, I could answer my own question more fully. But, where would one find such figures and for which population areas, which companies, which stores? Also, all of the equipment, used and new which sells via eBay, Facebook marketplace and other sites. No way that I know of to find sales figures.

Thank you for taking the time to read this article. My researching and writing this blog is a labor of love. Feel free to comment below or on Facebook. I write two other blogs: Pictures of Nancy. The Love of My Life. and People Say I'm Special. But I Don't Know Why

Scott Robb

March 13, 2025

#508