guitar equipment – Preservation Sound

This Was A Home For Animals

chris — Tue, 31 Jul 2012 10:14:36 +0000

Above: the result of five-hours work on a dead, dead, dead Univox 50-watt tube bass head. This model was originally designated the E-3 or the U-1236 (click here for the schematic). It was made in 1968, and it’s similar to a blackface Fender Bassman in many ways: fixed bias 50Watt output with a pair of 6L6s, 12Ax7 and 12AU7 preamp tubes, volume, bass, and treble controls, and a pair of switches marked ‘Sharp’ and ‘Deep.’ These switches are similar to the ‘Bright’ and ‘Deep’ switches that you would find on the two separate input channels of a Fender amp. Unlike the Bassman, the Univox uses an unusual additional balanced voltage amp between the phase inverter and the power stage. The Univox is also single-channel, it lacks middle and presence controls, and the power supply uses a voltage doubler.

Above, the Univox as I originally found it in a filthy old garage. It came with an empty pro-quality 2×15 ported instrument speaker cabinet; $45 was the total price. A bit steep, I admit, but I was feeling optimistic I suppose. I think a fair price for this thing would have been somewhere between ‘FREE’ and $25. Oh did I mention that it had no tubes in it either? I declined to take the speaker cabinet and it’s probably in a landfill now somewhere. Just can’t save ’em all…

Hey there! Here’s the horrifying scene I encountered when I removed the single (incorrect) screw that was holding the chassis into the cabinet. What you are seeing is a heartwarming combination of acorn shells, spider eggs, and ants. Long after this thing ceased to be a device capable of amplifying audio, it had a second life as home for wayward animals. Let the crack fox explain. (click text at left for direct link; full video below).

Oh yeah so – the horrifying part? Look at how this thing is constructed: a (basically non-removable) circuit board! With half of it obscured by sheet metal. This ain’t gonna be easy. Feeling a little less optimistic at this point…

Above: the reverse side of the chassis (which was remarkably clean) after allllll of the repairs were completed. Here’s what it took:

*When I found an appropriate-sized fuse cap and tubed the thing up, I attached the test speaker and I got… hummmmmmmm. That’s it. Lots of hum. Now as a younger fellow this would have discouraged me, but I’ve learned better. Hum may suck but it is SOUND, so at least the power transformer, rectifier, and output stage is relatively operational.

*I measured the voltages throughout the power supply – they were way off. One of the (factory-original) filter caps was so, so drastically underrated – 150v whereas it needed to handle at least 300v – so it’s a miracle this thing ever worked at all. Replaced all the filter caps (and the bias cap) and voila – some audio, a tiny, tiny bit, was passing from the input and the tone controls seemed to work. The B+ points were now also reading within appropriate ranges.

*After replacing the bias cap, the bias was reading 20v whereas the schematic indicated -32v. I was also getting two different readings at the 6L6 grids. I suspected the coupling caps, and sure enough, they were shot. replaced those and bias was now -28v and balanced. I little lower than the schem, but so was the B+ overall so probably correct.

*Next: started checking the B+ at every plate. ALL THREE 47K plate-load resistors were shot. As was EVERY SINGLE coupling cap in the amp. Replaced all of that stuff and the amp was working alright. Some hum, the tone sucked, but it was loud.

*As I was checking some voltages around the chassis I saw some sparking inside the output transformer. The O/T is a paper/wire wound unit with no potting or wrap whatsoever – the coils are completely exposed. Not a good idea. Anyhow, something, moisture, dirt, who knows, had gotten inside of it, and now that it was putting out some real current, it was starting to burn up. I had a spare output transformer (vintage US made unit from a discarded PA head) with the same turns ratio, same size and weight, so I threw that in. Now the amp sounded great! Almost done…

*Last steps: removed the two-prong A/C cord and the ‘Death Cap,’ replaced the DPDT power/standby switch (the original switch was intermittent), and put in a better-matched pair of output tubes (a pair of old Sylvania 5881s). I used 50s RCAs for the preamp. Hum is totally gone, everything works great. It’s really a great-sounding amp now – loud, versatile controls, and so small and light for a 50W head. Pretty good, pretty neat…

As far as the cosmetics go: one of the original knobs was missing and I didn’t have an identical unit in stock, so I replaced all three with some vaguely period-correct Japanese knobs. I also didn’t have a Univox logo plate to replace the missing original, so I added a name plate from the random-logo-drawer onto the front of the amp just because it looked a little odd with nothing there. Univox is now ready to go, much better than it was from the factory: better caps, better output trans, and much better tubes too. If this had been a repair for a customer, the bill would have been around $400 for parts and labor (assuming I used new Chinese or Russian tubes and a new O/T). $400 is clearly too much for a sensible person to spend on repairing a piece like this, as the street value for a properly working unit is only about $350. Had someone other than an amplifier serviceman purchased this thing, it probably would have gone into the trash or into another garage for the next 45 years. Now, if the Univox had been wired and assembled like a Fender amp, on a turret board, the repair would have taken half as much time and the repair could have been vaguely cost-effective. It was the goddamn awkward circuit board that made it take so long to re-fit. Proof yet-again that repairman-friendly construction practices do add significantly to the service-life of an amplifier.

Baby it’s the Guitar Dude

chris — Wed, 25 Apr 2012 10:28:29 +0000

1971: Ovation instruments of New Hartford CT releases “the Guitar Dude,” a 100-watt 2×15 guitar amp.

1972: Bread, the band that virtually invented lite-rock, releases the album and single ‘Guitar Man,’ one of the most melancholy songs ever written about the life of a rock musician, right there with Superstar and Turn The Page.

Who draws the crowd and plays so loud
Baby it’s the guitar man
Who’s gonna steal the show
You know, baby, it’s the guitar man

He can make you love
He can make you cry
He will bring you down
Then he’ll get you high
Somethin’ keeps him goin’
Miles and miles a day
To find another place to play

Night after night who treats you right
Baby, it’s the guitar man
Who’s on the radio
You go listen to the guitar man

Then he comes to town
And you see his face
And you think you might
Like to take his place
Somethin’ keeps him driftin’
Miles and miles away
Searchin’ for the songs to play

Then you listen to the music
And you sing along
You want to get the meaning
Out of each and every song
Then you find yourself a message
And some words to call your own
And take them home

He can make you love
He can get you high
He will bring you down
Then he’ll make you cry
Somethin’ keeps him movin’
But no one seems to know
What it is that makes him go

Then the lights begin to flicker
And the sound is getting dim
The voice begins to falter
And the crowds are getting thin
But he never seems to notice
He’s just got to find
Another place to play

Either way
Got to play
Either way
Got to play

Sex Sex Sex Sex (guitar accessories)

chris — Sat, 07 Apr 2012 15:25:50 +0000

No explanation necessary

I manage to do a fair amount of business selling bespoke microphone preamps, filters, amplifiers, etc; but I could stand to sell more. Perhaps the problem is my marketing technique. Perhaps I could stand to ‘spice things up’ a bit. Perhaps the vacuum tubes in my designs could be given a more phallic character through quasi-clever wordplay and/or illustration technique. Or perhaps the complete pieces could themselves entirely become metaphorically represented by a female body/persona, and the potential buyer could be encouraged to ‘inject them full of life’ with your ‘signal.’

Does sex really sell or do we simply gravitate towards the easiest possible metaphor for any product message? And if sex DOES sell, then why not ingestion? Eating? As important as procreation is to the survival of the species, a starving man will surely choose a cheeseburger over a romantic dalliance. Perhaps the dominance of sex-based, rather than food-based, advertising in our culture, signifies nothing so much as the fact that we’re not hungry enough. If we were hungrier, would be be less easily aroused? And how about the other two ‘F’s of human instinct (fuck, feed, fight, flight)? Why not more combat-based or fear-based advertising? All the ads in the series come from a single 1981 issue of GUITAR PLAYER magazine.

Which ‘bone’ exactly is the ‘mojo bone’? And how could this ‘bone’ interact with a ‘back door’?

If you have been feeling/touching one body for sometime now, consider the improved sensation that could be possible from… oh never mind.

The heels have come off and the couple has exited the scene. Crucial to the progression of the movement from LR to BR: the fire; the wine; the dulcet tones of your Ibanez Artwood. All helpful tools in mastering the art of (reproducing human) life.

Those who have mastered their technique need not execute their practices in a darkened room. Consider our mood lighting. Mirrored (balls/ceiling panels) sold separately.

Gibson Electric Guitars and Amplifiers 1956

chris — Tue, 13 Mar 2012 11:44:11 +0000

Download the twenty-page 1956 Gibson Electric Guitars and Amplifiers Catalog:

DOWNLOAD: Gibson_Elec_1956_cat

Products covered, with text, specs, and photos, include: Gibson Super 400 CESN, L-5 CESN, ES-5 Switchmaster, Byrdland, ES-175, ES-175 DN, ES-350T, ES-125, ES-295, and ES-240 hollow-body electric guitars, Gibson GA-90, GA-77, GA-55 V, GA-70, GA-40 ‘Les Paul,’ GA-30, GA-20, GA-6, GA-9, and Gibsonette amplifiers; Gibson Les Paul Custom, Les Paul, Les Paul special, Les Paul Junior, and ES-225 electric guitars; Gibson J-160 E acoustic/electric, EM-150 electric mandolin, Gibson Electric Bass; Ultratone, Century, BR-6, Console Grande, Consolette, Electraharp, and Multiharp steel guitars, plus more.

The 1956 GA-90 ‘High-Fidelity Amplifier,’ with six 8″ speakers and promised 20-20K hz frequency response (really?).

This very rare catalog is something special for fans of the electric guitar. We see a number of trends developing – the solidbody electric guitar, ‘true vibrato’ circuits in amplifiers, high-wattage amps… and a few notably absent: humbucking pickups and amplifier reverb. These were right around the bend though… Download and enjoy.

Original catalog image of the 1956 Gibson Les Paul Custom

Gibson’s 1956 ES-225T, the first of their many semi-hollow body guitars, the most iconic of which is the ES-335. I borrowed a friend’s ES-225T for a few weeks in high school and I still have very fond memories of it… great guitars, very expensive today.

The 1956 Gibson 350T. A slightly less-fancy Byrdland, also with a medium-scale neck.

The 1956 Gibson ES-140, their short-scale offering of the era. An artist whom I regularly work with at Gold Coast Recorders often brings one of these to sessions, and it is a seriously fun sitting-on-the-couch guitar with a seriously noisy single-coil pickup.

The 1956 Gibson GA-6, one of their most classic amps. Very similar to a Tweed Fender Deluxe. Fantastic amplifier.

The 1956 Gibson Les Paul. We have a clone of one of these (based on a 1972 Gibson Les Paul Deluxe) at Gold Coast Recorders and it sounds great. 1956 was an important year in the development of the Les Paul as it marked the appearance of the tune-a-matic bridge: it was now possible to intonate your guitar quickly and accurately, AND also customize the string feel and sustain characteristic by setting the stud to get the break angle that you want.

Carvin Co. electric guitars of 1978

chris — Thu, 28 Jul 2011 13:31:11 +0000

Continuing our series on Carvin Musical Instruments of the 1970s: the complete Carvin electric guitar line-up of 1978. Download a twelve-page scan of the 1978 catalog:

DOWNLOAD: Carvin_guitars_1978

Products on offer include: Carvin DC150C, DC150B, CM140, CM130, and CM120 electric guitars; the Carvin CB100 stereo bass, and the DT630 and DB630 doubleneck instruments.

By 1978, Carvin had abandoned the slightly Fender-influenced European-made guitar components they had been using since the late 60s; the 1978 lineup is much more Gibson influenced; or maybe Gibson-by-way-of-Alembic. Noteable late-70s trends at work here include: solid brass hardware; heavier (8.5 lbs) instruments; humbucking pickups with coil taps; ‘natural’ finishes; and plentiful control knobs/switches ala Alembic and BC Rich.

One odd holdout from the earlier era of the electric-guitar is the fact that these instruments shipped with a guitar-cable included. I wonder when this practice finally ended. Seems like a cable more ought to come with an amplifier than with a guitar… Also notable that the bass-instruments shipped with flatwound strings standard. I have noticed that there is a definite trend lately for electric-guitar players to use flatwound strings again; I have been really enjoying the sound of flatwounds on my 60s Fender and Harmony guitars; it’s kinda the secret ingredient to get the sound of 60s records (assuming yr using an old gtr and an old amp as well). The only problem is that they are more expensive. $12 vs $5 for roundwounds. On the other hand, they rarely break, and it’s not necessary to change them as often, as a ‘dulled’ sound is sorta the point.

Previous 1970s Carvin coverage on PS dot com begins here…

Out-Of-Print-Book Report: “Electric Rock,” Richard Robinson 1971

chris — Sat, 16 Jul 2011 13:35:41 +0000

“Electric Rock” (Pyramid Communications, 1971, 224pp) was written by Richard Robinson. It’s a small paperback volume, mainly text, which offers an assessment of hundreds of the guitars, basses, amplifiers, and PA equipment that were available to the American public in 1971.

There is also ample text devoted to basic explanations of subjects such as ‘What is a piggyback amp?’

And in case you were wondering:

Try saying “The Shape Most Often Used For Rock Is Darkened In” 10 times. It will assume a mantra-like quality. And then you will know the shape of rock (darkened in). “Electric Rock” is filled with plenty of such slightly-off prose. It’s written in a circa ’70- streetwise-hipster voice, and this is not at all surprising once you learn a little about the author. Richard Robinson is a fascinating character. His slightly mean-spirited AllMusic profile tells most of the story. RR is most famous for co-founding ‘Rock Scene’ magazine and for producing Lou Reed’s unsuccessful first solo album. But he also produced a few of my personal favorite records of the era. Check these tracks out…

Teenage Head by the Flaming Groovies

Sifting Around In a Haze by Andy Zwerling: 06 Sifting Around In A Haze

Reachin’ by Hackamore Brick

Anyhow. Point is, RR had his finger on the pulse of a lot of music which would never amount to much commercially, but which has very much stood the test of time artistically. Kinda like… Reed’s first band the Velvet Underground. Pretty interesting… this guy definitely knew what he was doing.

In case you’re wondering what ever happened to Richard Robinson, well… apparently, here he is in 2007. Different line of work. Life is funny, huh? RR, if you are still out there, drop us a line.

Oh BTW one more thing to add about “Electric Rock”: Lenny Kaye wrote the forward. The-Lenny-Kaye as in, created ‘Nuggets‘ (basically the holy canon of Garage Rock) and also plays guitar (since the ’70s) for Patti Smith.

Check out ‘Electric Rock.’ One copy currently available at Amazon dot com.

Carvin Guitars, Amplifiers, and PA equipment: 1973 Catalog

chris — Wed, 13 Jul 2011 14:19:20 +0000

Download the thirty-two page 1973 Carvin catalog (presented in two sections):

DOWNLOAD AMPS, SPEAKERS, AND PA: Carvin_1973_part1

DOWNLOAD GUITARS: Carvin_1973_part2

Products covered, with images, specs, and text, include: Carvin Lead amps LM1000, BL1250, FR1200, LP600, SM450 and TM565; Carvin Bass Amps ABM850, BM900, BM355, and FH2500; Super Amps SBL2000, SLM1600, SABM1800, and SBM1900; Combo amps VTR-212, ML212, and MB212; Tube amp head VTR2500 and TV2500; Solid-State heads ST4000, ST2400, B3000, B2000, and B1500; Carvin P2500, P4500, and P5000 PA heads; plus numerous speaker cabinets and components.

Guitars and bases include: Carvin AS50B, CM95, SS75B, SS65B electrics; Carvin SB60, SB40, and AB45 bass guitars; DBS98B and DTS90B doubleneck guitars; PRO-S8 and PRO-D6 steel guitars; plus more.

Above, some of the new offerings for 1973: we see a Folded-Horn bass enclosure (popularized by ACOUSTIC corp in the early 1970s); we see a return to tube amplification in the form of the VTR2500 amp head (seems similar to Ampeg V4 of the era); and we see a larger PA head with 8 inputs and some sort of quasi-notch filtering: power output is 170 watts into 4 ohms. Can anyone hear the singer?

1973 Carvin AS50B. AFAICT, this instrument uses the same body as the earlier OVATION “Tornado” guitar.

The 1973 Ovation SB60. Identical to the cheaper SB40 save for the 1.5lbs heavier maple body. We’re near the start of the unfortunate ‘heavier-is-better’ guitar trend of the 1970s.

Doubleneck guitar/mandolin has been replaced by doubleneck guitar/12-string guitar.

Guild CopyCat tape echo has been replaced by Maestro ‘Sireko.’ Anyone out there have any experience with the merits of one vs the other?

Carvin Guitars, Amplifiers, and PA equipment: 1971 Catalog

chris — Tue, 12 Jul 2011 13:16:18 +0000

Download the thirty-two page 1971 Carvin catalog, presented in the original glorious black-and-white (9.9M zipped file):

DOWNLOAD: Carvin_1971_Catalog.pdf

Dig the excellent non-designed cover. Products covered, with pictures, specs, and text, include: Carvin Super Band Leader amp SBL2000, Super Lead Master Amp SLM1600, Super Bass Master SBM1500, Band Leader BL1100 and BL1200, Lead Master LM990 and LM1000, Carvin Altec -equipped Lead and Bass Masters, Bass Master BM 755 and BM 775. Public-Address (PA) systems/components include: PA5000 incorporating P2200 head and CR 150 speakers, PA600 featuring P3500 head and SR660 speakers, System 7000 featuring P4500 head. ‘Compact’ instrument amplifiers include Twin Master TM550, Lead Performer LP400, Bass Master BM340. Amplifier heads include Carvin B3000, B1600, B2400 and B1050 Bass amp heads or ‘Power units’ as Carvin calls them; L4000, L2500, and T2000 Lead Power Units, aka Guitar heads.

Guitars covered include: Carvin AS50B and AS50 hollowbody electrics, SS70, SS70B, SS65B, SS65 electric guitars, AB45 and SB40 electric basses, ABS95 bass/guitar doubleneck and AMS90 Mandolin/Guitar doubleneck; Carvin pedal steels # 41B, 61B, 81B, 101B, and 1010B; Carvin steel guitars PRO-S8, PRO-D8, PRO-D6; plus a range of parts and accessories.

1971 Carvin AS-50B Acoustic-Electric Guitar

1971 Carvin SB40 Electric Bass

1971 Carvin APS95 doubleneck

As far as i can determine, Carvin used imported European bodies for their acoustic electric guitars (similar to what Ovation did at the time) and imported the necks as well. I am honestly not sure if they made their own solid-bodies, but given that they were making amplifier cabinets, I can’t see any reason why they would not have. When you look at these guitars, the overall vibe is not Fender or Gibson… I feel like the closest comparison is the work of fellow Californian Paul Bigsby.

(image source)

BTW, if you have not read Andy Babiuk’s excellent book on Paul Bigsby, spend the $32 and check it out. Far and away one of the best books ever written on the subject of a musical-instrument innovator. NEways…back to Carvin…

1971 Carvin Super Amp

1971 Carvin L4000 amplifier head

The most interesting thing about the amplifiers is the construction method used. Years after even tube-based electronics had begun using printed-circuit-boards, Carvin was using point-to-point wiring for their all-solid-state amps. The amplifiers ranged in power from 80 watts into 4 ohms up to 160 watts into 4 ohms (2 ohm capable).

Guild CopyCat Tape Echo as offered in the 1971 Carvin Catalog

As Carvin still does today, the catalog also includes accessories made by other manufacturers, as well as part and encouragement to ‘build your own!’

Plenty more on offer within the catalog. Download and see…

Tomorrow: 1973.

Gibson Guitar Amplifers: 1966

chris — Sat, 25 Jun 2011 12:40:28 +0000

Download a twelve-page scan of the entire guitar-amp line represented in Gibson’s 1966 catalog:

DOWNLOAD: Gibson_amps_1966

Models covered, with specs and photos, include: Gibson GSS-100, GSS-50, and PLUS-50 solid-state amplifiers; Gibson Titan, Mercury, Atlas, and Atlas Medalist (Bass) amps; Vanguard GA-77, Apollo GA-95, Multi-stereo GA-79, Ranger GA-66, and Saturn GA-45 Reverb/Tremolo amps; Lancer GA-35, Minuteman GA-20 RVT, Explorer GA-15 RVT, Recording GA-75 and GA-75L, Skylark GA-5 and GA-5T practice/studio amps.

Above is some of the most awful product-prose that I have ever encountered, taken directly from p.16 of the 1966 catalog. ‘Butterflies, Stroking, Squeezing the full measure …..’ Were these people fucking high? Actually, the problem is that they probably weren’t high. Yet. 1966 seems to have been a decisive year in musical-instrument marketing; the very last year that manufacturers denied the very existence of Rock and Roll. Most of the catalogs and advertisements from 1966 (and earlier) were very staid, grown-up, and had a romantic rather than… aquarian… sensibility. In 1967 we start to see the bright colors, bold graphic design, and general emphasis on youth that remain in most musical-instrument marketing even today.

Above, the Gibson Atlas. What a beautiful piece of industrial design this is. After I came across this catalog, I looked for any examples of this unit for sale. I could not find a single one. While I am sure that the Gibson Atlas did not ship in nearly the same numbers as, say, a Fender Bassman, there is another reason that these 60’s Gibson amps are not too common today: reliability and build quality. While Gibson amps of the 1940s-60s are excellent sounding in general, Leo Fender really had these midwesterners beat as far as construction quality. Earlier this month I serviced a couple of early 60s Gibsons for a client. Opening up a mint-condition Gibson circa ’62 student amp… I can’t recall the model, but it was a PP 6AQ5 amp with fixed-depth trem… anyway, opened it up to find a few haphazardly placed terminal strips, and even a few multi-component junctions meeting in mid-air. This is in sharp contract to the build of even the cheapest Fenders, all of which have carefully laid-out, serviceman-friendly terminal boards. The same construction techniques you will find in much military and commercial hardware of the pre-PCB age. This is not surprising when you remember that Leo Fender began his career as a radio repairman rather than as a luthier or musician. As you (IF you) learn to design and build tube audio equipment, take some time to open up as many old pieces of hardware as you can find. $2, $5 pieces… old test equipment, radios, organs… check out the construction and mounting techniques, lead dress, solder joints… you will find a huge variety of techniques used, all of which will have some useful applications in your own work. This is all the stuff that can’t learn from schematics, and certainly not from reading (blogs) online.

Heathkit Rock-Band Hardware c. 1969

chris — Fri, 17 Jun 2011 18:19:18 +0000

Download a five-page scan of the various guitar amps, guitars, effects, and other Rock-combo-flotsam available from Heathkit in 1969:

DOWNLOAD: Heathkit_guitar_amps_1969

Products on offer include: Heathkit Starmaker TA-16 amplifier; AKG and Shure mics and Atlas stands; TA-27 guitar amp; Harmony ‘Silhouette’ H17 electric guitar; Heathkit TA-28 “Fuzz” Booster and TA-58 headphone amp; TA-17 amplifier head and TA-17-1 speaker system; TA-38 bass amplifer (130 lbs!); and a kit version of the famous Vox Jaguar organ.

M. and I were digging through some local pawn shops last week and we spotted the above-depicted ‘Starmaker’ amplifer buried under some radial arm saws. Coincidentally enough, the price they were asking was the same $119 that it would have cost you to buy as a kit in 1969. “…in about 8-10 hours and you’ll have the best value around in a solid-state amp. Order yours now.”

Kit-built electronics were a fascinating and vital part of consumer-culture in America through the 1970s. It’s kind of liberating when you think about it: a product which parses out some (but certainly not all) of the labor from the physical materials of the product; you, the consumer, can then create the finished product from a combination of your capital (money) and your raw labor/time. I am about to do the same thing with a shed; we need someplace to put our lawnmower, and the right balance of capital/labor for my particular circumstances is a shed-kit. I have neither the money to pay someone to build a shed for me nor the free time to build a shed from a blueprint and a pile of uncut lumber; the shed kit seems like the right choice for me. At some point in America, the value of the labor required to complete a piece of consumer-electronics equipment fell below a certain point, thanks to a combination automation (robots) and cheap foreign labor. This made the Heathkit a fairly indefensible option. This affordability of foreign labor (and transportation costs…) can’t last forever though. So I have to wonder: as foreign labor prices continue to rise, will we ever see a return of the kit-option for consumer electronics in America?

Do you ever come across a Vox Jaguar and wonder why it does not work quite right? Well now we know: it could have originated as one of these kits; 91 lbs of cold solder joints and sloppy lead dress. Heathkit makes a bold claim about the capability of the above Jaguar when used in league with their TA-38 bass amp: “Here’s a combination that will produce the most mind-bending, soul-grabbing sound around.” 266 lbs, $499.00.