Rollin' and a Tumblin' at Ronnie Scott's

Fellow blogger Bill (hmm, there's a blues lyric in there somewhere) recommended the Jeff Beck at Ronnie Scott's DVD with his highest praise just the other day. And then I stumbled on this number with Imogen Heap on vocals. Stellar guitar work from Beck and I have been a fan of Heap's since her Frou Frou days. She is not a blues shouter but the visual and vocal counterpoint works well. Beck's never been a beaten path sort of player and this collaboration with Heap is inspired.

Beck has long been a favorite. I saw the first two Beck, Bogert and Appice performances live in London in '72, and again that following spring in Syracuse. They were fronted in the 'Cuse by Wet Willie, a bit of creative scheduling that left me baffled. Jeff Beck having to follow a group named for sticking a saliva gobbed-finger in someone's ear, what was the world coming to? Keep on Smilin' I was not.

But enough. Jeff Beck:



Ok, now for a bit of wallowing in the '70s. First up, my initial encounter with Stevie Wonder's Superstition was this one:



That's Timmy Bogert and Carmine Appice backing Jeff Beck. I had been a Vanilla Fudge fan and this other band featuring Bogert and Appice:



Rusty Day was on vocals and Detroit's own Jim McCarty was on guitar. I caught Cactus in '71 at the Syracuse War Memorial, following Chase (!) and before Black Sabbath. Great seats and a great show.

I Buy My Dehydrated Boulders and Integrated Circuits From Acme

The Acme Company is the source of the amusing products that Wile E. Coyote uses with less than stellar success in his pursuit of the Road Runner. While they do not sell rocket sleds, Acme Enterprises of Orlando does supply name brand integrated circuits at reasonable prices and with good service. They evidently got their start supplying large hotel chains with the quality parts they need to maintain the gazillion room tvs they own. Who knew?? Someone actually fixes tvs.

I can also recommend their Quick Braid solder wick. I am not sure it is exactly Chem-Wick quality, but it is certainly close enough that I can happily pocket the savings and not worry about it. Good wick makes for tidy work. Or something like that. It certainly makes the work go faster. Anyway, Mike approved and he uses this stuff in feet per day. The big 100' spool will last me a year.

Lil' Mar: Step #1

Lil' Mar is a petite Marantz 4220 quad receiver from the mid '70s. Or, as the faceplate says: 'Stereo 2 - Quadradial 4'! Orion says it was sold from 1974 to 1978 and retail list price was $329. The more authoritative Classic-Audio.com says it debuted in '73 and listed in '74 for $299. It was the smallest and lowest powered Marantz quad receiver. Orion says it packs 15 watts per side (stereo, I assume), but Classic-Audio.com lists it at 2x20 or 4x8. It is not exactly a powerhouse, even by the standards of the mid '70s, but I imagine it would drive a dorm room 2 channel rig quite nicely. As for quad, I hope they chose their speakers carefully.


Lil' Mar is not a standard sized component. It is only 14" wide; the similarly powered stereo 2215 is 17.25" wide. Classic-Audio.com lists it at 16.875" wide, but that has to include a wood case.

My initial listen was not particularly favorable. One channel was down in volume and noisy. At the very least I wanted a stable amp that would play vinyl well, so recapping the phono, regulator, and output sections was mandatory.

Cramming 4 channel gutti-wuts into such a small space required some engineering trickery. The regulator was relatively easy to access at front right, but the amplifier was going to be a bit complicated. The heat sink occupies the center of the unit with the board on its left. This is not a pop-out like the wonderful Marantz 2275. It's more of an unscrew/tug/unscrew sort of effort so I decide to procrastinate a bit and save it for next time. In the photo below the tuners are at the left, nicely shielded as Marantz is wont to do.

Underneath you can see the preamp/tone control circuitry at the right, behind the faceplate. It's a bit daunting. The board just above the heatsink is the SQ quad circuit board. All the way at the top you can just make out the phono board, facing down.

I removed the two screws on the regulator and recapped it with Panasonic FCs and FMs while it was still tethered to the wires connecting it to the rest of the amp. They were a bit short, so it was a bit awkward soldering. If that engineer had specified just another half inch of wire I would have complimented his foresight at this time. But, no.

The phono section was much of the same: two screws and some tugging. It is mounted to the side of the chassis, under and to the left of the tuners. Marantz phono sections tend to have a significant number of film caps, but not this one. It has 8 electrolytics, 4 films and 4 ceramics. If I recall correctly, the 2275 has a single electrolytic cap in the phono section. So I could feel good about myself I replaced the two output coupling caps at the far right with Elna Silmics at 22 mfds instead of 10. The rest were replaced with Panasonic FCs. Here is the phono board 'before'.


All in all, I replaced 12 caps, fired it up and the amp was stable. So step #1 is complete and the next trip to the bench will deal with the amp itself.

Cleaning Up the Archives: The Sony ST 4950 Tuner

I checked out this acquisition a few weeks ago and have been in a lazy funk due to the systemic shock of 8 to 5 employment. And you know what they say about procrastination... Anyway, the archives have now been diminished by one.

The ST-4950 is a handsome tuner, and is really a surprising cosmetic given the vintage. According to the wonderful FMTunerInfo.com it was sold in 1977 for $350, but the matching TAN-8550 power amp (coming soon!) service manual in my possession is dated 1974. I think this cosmetic is a forerunner of the early '80s look, although better executed than those that followed.


After a scrubbing the garage grime off the exterior, I popped the top prior to plugging it in. A visual inspection can save some heartache and it might have in this instance. The cap at the far left was visibly leaking so it was replaced. I squirted a few switches and the tuning capacitor with Deoxit and fired up the unit.


It worked great. This day on the bench was a short one, so just the single cap was replaced. However, I am going to have to have a Sony re-cap orgy in the near future and get the amp and tuner going with fresh parts. They deserve a very critical listening. Their build quality is very, very good and the amp is an especially desirable unit. Stereo Club member Paul, supplier of the amp service manual, is a very big fan of the Sony V-FET gear and has strongly recommended their addition to the Permanent Collection.

Oh yeah, what about that honking big hole in the chassis? I should point out that most of this line of tuners featured the now obsolete Dolby FM. This particular model did not, but I presume it shared a chassis with either the 3950SD or the big dog 5950SD that did. In this case less is more and the lack of Dolby is a good thing.

For you fans of classic hifi porn, here is the Sony ST-5950 as presented by the Vintage Knob.

The Alamo Jet Guitar Amp

Time for something completely different, music creation instead of a music reproduction! Tube instead of solid state (mostly)! Here, in Fenderish garb is the 4 tube, single ended 6V6, Alamo Jet from around '65 to '67:


Alamo Electronics was based in San Antonio (natcherly) and had an interesting history from '46 through about '82. As far as I can tell Alamo was never a premium manufacturer, but their amps have acquired a following, especially here in the Lone Star state. The Jet seems to fit nicely as a harp/practice/small venue blues amp.


This amp was in very respectable and original shape, but the last time it was used by one of the boys it was a bit noisy. That was quite a while ago, and I was nervous about firing it up without at least a basic refurb. So it was time to hit the bench.

This is a very basic point to point amp with a minimum number of caps. The 3 section main filter can was a 20@450v/20@450v/20@25v that was in marginal shape. The high voltage sections were hanging in there but the 25v section read high on the ESR meter. Forty year old electrolytics make me nervous so the can had to go. I resolved to just bypass it with caps under the hood and made the mistake of asking Mike how he would approach it. Mike whipped out the big clippers and popped the 3 tabs under the hood free. I really have to quit asking questions with obvious answers.

We resolved to up the values to 47@450v/33@450v/47@63v with Panasonics EE series caps for the high voltage caps and an FC for the other. I replaced the two 10mfd@25v caps with films @100v. Three orange drops and a Panasonic FC 47@63 brought the cap count to a very modest 9. I left the bevy of ceramic caps for another day.


The amp powered up nicely on Mike's Sencore Powerite and was stable, so tomorrow we will see how it sounds.

One note: the several solder points to the chassis were extremely tough to melt. It takes a hot gun to make headway on this amp, I guess the chassis functions as a very big heat sink.

Interestingly, I could not find a Wikipedia entry on Alamo. C'mon guys. But I did find several very useful links. Here is a part 1 of a very good history of Alamo Electronics in Vintage Guitar. And here is part 2. This article indicates '65 marked the transition to the black tolex, so the would be the earliest date of origin for my amp. The part 2 model summation seems to describe my amp cosmetically as in the '65-'66 range but it definitely has two small transistors in the tone control circuit. And it is missing from '65 line up, but I would think that is an omission. Maybe. The early '70s seems to be the transitional period for solid state, so it beats me as to the vintage of my Jet.

And here is a much more thorough restoration/augmentation of what appears to be a bit later version of the Jet, model 2564. My Jet was missing the sticker on the inside so I am not sure of my model number. Evidently Alamo was a bit cavalier with their names and model numbers.

And here are some good pictures of what I also assume is a later Jet, and please scroll to the bottom to view the reverb. Funny. I assume this is an original and not a replacement.

One last digression. In about 1982 Alamo Electronics merged with Southwest Technical Products of San Antonio. In that year I did a pilot software project on a SWTP Uniflex 6809 mini/micro for the state of Texas and demo'ed it for the Governor's office. Ahh, memories. Anyway, SWTP was also a hifi manufacturer of note and deserves some attention from the Stereo Club at some point in the future.

HD Radio Self Noise Etc.

I guess I should supply a warning: serious technical wonkery ahead.

Paul, a member of the Stereo Club before it even existed, sent me this marvelous link on the topic of HD radio self noise, otherwise known as digital side band hiss. The author is Brian Beezley. This is a very dense exploration of the effect and its mitigation, complete with 8 by 10 glossy photos and a list at the end of vintage tuners that might avoid the issue to some degree. Highly recommended despite the trepanation required to relieve the pressure on my brain.

Paul also included this equally informative link on the remarkable Sony XDR-F1HD tuner. Let Paul talk for a moment:

I have this tuner and the specs documented on this site are true. Reception of analog signals is unbelievable. It isn't the best sounding tuner but its front end and IF selectivity performance is without parallel. Simply put, I receive, in stereo, stations I've never heard on the dial before. It's a cheap $100 plastic box and HD radio isn't the best sounding for FM but as a signal grabber, it's truly amazing.

And lastly, here is Brian Beezley's web page. Impressive.

Yet Another Video Oddity: the JVC XL G512NBK CD Graphics Player

I was vaguely aware, back in the day, of the CD graphics player, but the whole idea seemed... odd. Pumping a still picture to my tv while listening to a cd just seemed something less than a thrilling use for my entertainment dollar. Karaoke is obviously not in my bloodstream, I guess. In recent years I have seen one or two cheapish Memorex cd graphics players on the hoof, but they never seemed of a quality worth examining. Recently I found the well built JVC XL G512 (G12NBK on the back! The mind boggles...) cd player that seems to be a different animal.



Wikipedia summarizes the CD+G format nicely, and here is one of the web's magnificent obsessives who happens to specialize in the format. Where would we be without these guys? Without the web he would be an obscure crank, but with it he is transformed into a historical resource. May I offer a tip of the Hatlo hat!

JVC cd players have never been on a wish list, but I stumbled on this one and was intrigued. It was heavy and from August '89, good signs. Orion says it was 500 bucks new, a non-trivial amount. It was relatively clean and reasonably complex, so how could I say no?

I took it by Mike's and popped the top and was happy to see innards of substance:

The transport was definitely a cut above, as was the laser assembly. It worked flawlessly and sounded very good. Note the two boards on the right. The smaller board on top is the video board with video, S-video and midi out. Might I say far out. Underneath is a real main board with a significant number of film caps, always a sign someone in Japan truly cared. The front advertised 'Noise-Shaping 18 bit', '4 Times Over Sampling Digital Filter', and 'Dual DA Converter' so this was evidently a serious attempt at a quality player.

One negative: the top was among the chimpiest flimsiest I have ever encountered. In a way it was encouraging: all the heft was in stuff that mattered. But beware, it will bend if you look at it wrong.

Many modern dvd players function very well as cd players, the theory being the technological bump up to handle higher bit rates inherent in movies requires better digital to analog converters. Mere music is a walk in the park, so to speak. There are lots of dvd mod'ers out there taking advantage of this by souping up their analog sections for a great sonic bang for the buck. Perhaps the XL G512 enjoys a similar benefit with the addition of the cd graphics capability kicking the quality up a notch. I did not have a chance to pull the video board and check the main board out in full, but this might be a very interesting candidate for a cap upgrade.

Update: my fellow poster has pointed out my inadvertent slur of the noble bonobo. Sometime in the past 'chimpy' entered my vocabulary as some sort of amusing amalgamation of 'chintzy' and 'wimpy'. It has now been corrected. For what it is worth I straightened several significant dents with my thumb. Flimsy it is.

Amusing But Obsolete Technology #1

Gearhounds tend to have a bit of a soft spot for interesting technology that was crushed by a disinterested market place. The case at hand: the RCA Selectavision Capacitance Electronic Disk (CED) video system. Released to the world at roughly the same time as the Laserdisc and its optical pick up, the CED system actually uses a needle that tracks the disk and renders the movie via modulated capacitance. Really. I am not capable of making this up. Ok, I am, but I swear I am not.

RCA Selectavision seems to have lived from 1981 until RCA was purchased by GE in 1986.

One still occasionally comes across the interestingly packaged 12" disks in thrifts, usually Butch Cassidy. The disk actually lives inside the hard plastic sleeve until loaded into player. The sleeve is removed and the disk stays. But the players are very rare these days. Until two days ago my last encounter with a player was about 10 years ago. Laserdisc players are much more common, maybe approaching 100 LDs for every Selectavision player that I have ever encountered in a thrift. Selectavision died young compared to laserdiscs.

A few days ago I found an RCA SFT 100 in very good condition for $4.20 after my my 30% senior discount at Savers. (I was shocked to see that this same player went for $305 on ebay recently. Wow.) As a resident in good standing at the Home for the Easily Amused, I made the purchase and took it by the Home, otherwise known as Austin Stereo Service.


Mike happened to have a few disks around and 'Pumping Iron', the movie that eventually led to the bankruptcy of California, was tried out.

After a few missteps akin to Gerry Ford eating the corn husk with the tamale we fired it up and it worked!


Here is Arnold's bicep attempting to devour Mike's tv. The observant among you will note that the player only draws 38 watts while pumping Arnold out to the screen. The picture quality was quite good. This format's ability to fast forward is truly astounding. You can rip to the end of the video in seconds in non-display mode, and fast forward display retains its video quality.

All in all this player was a great addition to the Stereo Club collection. Now we all need to pull those Selectavision disks we have been saving out of the closet and see how they look...

The Magnum Dynalab FT 11

This FT 11 arrived working but without stereo. This very well built, compact, and stylish tuner from '88 or so had a list price of $495. It was the bottom of the Magnum Dynalab line with the FT 101 ($885) and the Etude ($1295) above it.

Popping the top revealed... not much. I discovered (according to the wonderful FMTunerInfo.com) that this was the original version of the FT 11 based on the board color. No tuning capacitor, just some chips, a few discrete components and some air. Given the vintage it was time for a cap job.



Unfortunately, the FT 11 is pan built. No bottom cover, bummer. You need to pull the main board after desoldering the antenna leads, unscrewing the rca jack plate and detaching the face. The cap count was a very modest 20 or so, replaced with Panasonic FMs, FCs and a few metallized stacked films. I replaced the 4.7 mfd output coupling caps with 22 mfd Elna Silmics. The board was easy to follow with stout traces:



I stitched the FT 11 mostly back together and fired it up. Weird. It would not tune properly, it was seemingly stuck on a crazy, out of range station. Mike took a look and said: 'Bridge.' I checked all my solder work and it looked good, but dutifully started scraping resin. Yowza! Underneath a small puddle of resin was a thin flash of solder bridging a circuit. A touch of the iron healed the bridge and the FT 11 fired up in stereo.

FMTunerInfo had suggested switching op-amps to improve the sound. I did a bit of research and discovered the installed NE5532 was a 50 cent part these days and that decent upgrades could be had for $2 to $12. Not exactly breaking the bank. I ordered a few TI bifet op-amps from Mouser: OPA2604AP ($4.27) and OPA2134PA ($2.42). And also the Analog Devices OP275GPZ from Digi-key. I should have gotten savvy and soldered in a chip caddy so I could swap them out, but that will have to wait for next time. I soldered in the OPA2604AP and fired it up. Note the brown Silmic at the lower right corner.


All was well, except now the stereo had vanished. Why, I have not a clue. I whined a bit and Mike took a twirl at the adjustments with the little plastic screw drivers and the stereo returned. I gotta get a set of those screw drivers. Whenever I ask for them Mike insists on doing it himself.

The modified FT 11 is a nice sounding tuner. It must have narrower filters than the '70s receivers I work on because KMFA, 89.5, sounded good. No hiss so Mike deemed it 'digital ready'.

I recently exchanged a few emails with an old friend and tuner guru who has been published on FMTunerInfo.com, and he has provided some excellent guidance on resolving the digital hiss issues in vintage tuners. More on that in the (hopefully) near future.

The Onkyo 2500 MK II Receiver: a Tale of Two Dohs!

We have for your consideration the Onkyo TX 2500 MKII, the second of the 4 receiver Onkyo range from 1978-80. The 2500 listed for a not insignificant $360, the equivalent of about $450,000 in current dollars. For the sake of comparison the big dog, 100 watt, TX 6500 MK II listed at $650. Back in the day that was about 6 weeks take home pay for me, and was $250 more than my mortgage.



This unit was evidently last used in a barn or garage; it was filthy, but as often happens the thick pelt of dust and fur seemingly preserved it from the daily nicks and knocks. A thorough detailing left it close to pristine except for an extremely annoying bent tuning knob shaft. Not trying to straighten it is like not picking at a scab, but it worked and it's usually not worth the risk of making it worse. That last trip to the thrift or flea market is the primary source of hifi trauma.

Orion says the 2500 is capable of a tidy 40 watts RMS, no doubt a conservative rating. It has been my experience that the medium powered receivers of the '70s sound very good when just a bit of care is taken with the choice of speakers. The 30-50 watt-ers seems to occupy the sonic sweet spot, with a bit more slam than their lesser brethren, but without some of the complications that can creep into a bigger box. Simpler is often better. I also assume that much of what I hear is the result of price point design decisions unrelated to absolute wattage. It could be bigger main filters than the lesser units or outputs that hit a happier part of their thermal range. At any rate, that elusive mojo can show up almost anywhere, but the middle of the pack seems to be a good place to look.

This particular 2500 had one channel in the dumper and the usual noise in the other. I checked the amp transistors and all was well. I checked the output of the preamp and the channel that was down was extremely low, so I expected that a recapping would get us rocking. But... no. In an object lesson of 'look for the obvious, stupid' Mike pointed me towards the fuse block on the back of the unit. Yup, one was blown. Evidently there had been an event and a fuse had given its life to protect a speaker. Fuses on the back? Who knew? That was doh! #1.

The restoration replaced 54 caps with the usual suspects: Panasonic FMs and FCs with a few stray metallized stacked films. The 2500 has 4 boards: power supply, amp driver, preamp and the combo FM/AM/phono. The latter 3 were straight forward although the preamp was a bit cramped as usual due to proximity to the front panel controls. The power supply board is mounted upside down under the main filters. It had to be unscrewed, wire ties clipped, the main filters clamps unscrewed and some tugging before it succumbed to the iron. The 6800mfd @ 50 volt main filters were left as original. If I get ambitious I might double their values someday.

Here is the underside: very tidy. Note the power supply board at the lower right.


Here it is from topside:

Richard Avedon I am not. At least the photo is in focus. Sort of. Below is a close up of the tuner board in the vicinity of the leads to the lamps. Nice, eh? It is so well labeled that even a solder monkey like myself can follow it. No spatial relations brain squeeze when I try to figure out where the leg of a cap is. Many a resistor has been mistakenly desoldered from poorly marked board...



Onkyo has a reputation for quality tuners, and here is where the tale gets complicated. The fm tuner is a phase-locked loop (PLL) with nice meters for signal strength and center, and 3 lamps: locked, tuned and stereo. FM stereo worked but the other two lamps did not. The locked lamp was burned out and replaced successfully, but the tuned lamp was good, and would not light up. Drat.

Poking through the circuit revealed nothing that was obviously wrong; all the pertinent transistors seemed fine. So I took the easy way out. Sometimes it is easier to spend some money than to exercise your brain pan. I had an order pending to a new vendor, Acme Electronics, so I added a new FM chip, the BA1320 for $2.39 to my shopping cart of anvils and dehydrated boulders. Oh, and another FM chip and a big roll of solder wick. More on that later, perhaps.

Well, as you might expect, the new chip did not solve the problem. Hmm. So it was time for the 'A' team to track it down. Mike puttered for a few minutes and then determined that I must have missed testing the offending transistor: a C380 adjacent to the where the tuning knob connects to the board. Doh!



The impedance of your hand on the tuning knob alters the circuit and turns the lamp off. Below, note the white wire that connects the knob to the board. Just to the right is a pair of black transisitors. The upper was the offender. Note the light bulb on the board where the white wire connects: it's there to absorb a whack of static electricity when you grab the tuning knob.



Anyway, the 2500 is now in fine fettle. The tuner sounds very clean except for the digital side band hiss that pollutes KGSR (107.1) and KMFA (89.5). This leads inevitably to tech jokes, eg. 'this tuner is not digital ready', or 'that sure is an accurate rendering of digital hash'. Anyway, it sounds great on a stations that have not yet embraced the dark side of Ibiquity. I really need to track down tuner tweaks to avoid the hiss.

I am rolling this article out the door without significant critical listening, stuff is piling up on the bench. So, with luck, I will tack on an update on how it sounds in a week or so.