What's the deal with old, cheap marantz receivers?

Let's not forget another venerable US brand based in Los Angeles, SAE. I have a rack full of their last good gear before it all became off-shored. James Bongiorno designed some of their earliest pieces but left to start GAS and Sumo, IIRC.

 

Oh yeah SAE was the thing back in the 70s. Even as late as the 1980's, the US made pieces remained popular. I recall going to a doctor's appointment, this must have been around 1989 or 1990, and I saw a couple of doctors discussing some papers. Instead of X rays or lab results, they had some SAE brochures and both were enthused talking about the gear!

James Bongiorno is one of my audio heroes. Quite the character!

 

The problem with Spectra Sonics for the consumer is that there was not a traditional amplifier in a chasis. The power supply was an open rack model taking up 5.25" of rack space. Then there was the card frame which was another 3 1/2". I think there were 8 slots, so one could use a Spectra crossover card, and also have a tri amped stereo system (6 amp cards) or any other configuration. There were provisions for operating each amp single ended or as bridged pairs. Unfortunately they didn't use a phase splitter before the amps. What they did was to take an inverting feed off one amplifier and feed it to the input of a second. This was not an ideal system, but easy enough to change.

OK to use this system, one had to wire the card rack to whatever configuration they wanted, and then wire the power supply up to the card rack. Then you need a rack to mount these two pieces to. You still have no volume controls. You must hook your speakers right up to the screws on the card rack. There are no input or output jacks of any type. Everything had to be custom wired.

Definitely not consumer friendly. When I had this for my home stereo I only knew of one other person who had a similar rig. Of course there were some studios that used them for power amps, but not many.

We used them primarily for PA. We had designed custom tri amped slant floor monitors with JBL drivers that used three bridged pairs and one single ended amp per monitor. They were most amazing monitors and almost everybody who heard them wanted them. I got a lot of job offers from bands because of those monitors and they're ultimately how I ended up with Seals & Crofts.

 

Yes we had a few SAE's at Sound West, but they were not reliable enough for our needs. That said, there were a few touring sound companies that did use them, and don't forget BGW as well. Lots of those were used professionally.

As for GAS, we had about a dozen of their amps at Dawnbreaker and there was always trouble with them blowing due to overheating. OTOH, they sounded great. I installed them, but they were stacked in a tall rack in the control room with the processors and we had 4 huge Augspurger monitor speakers that were often blasting at ear shattering levels. I ultimately had to build a cowling behind them and run AC through it.

Consequently, I made many trips to the GAS factory and often was in there while the amps were being repaired. It was just down the street from the studio. Jim was frequently there and was very down to earth. In fact, I came up with the idea for the cowling while talking with him. I never wanted to mount the amps that way. I felt they should have been in the soffets by the speakers, but I was outvoted. They did look cool where they were, but it was a pain. Plus we had long speaker runs.

 

Here is a deal on the Marantz 500. Not sure if the seller is from Brazil.

http://cgi.audiogon.com/cgi-bin/cl.pl?ampsmult&1197598119

 

The Mc tube power amp chassis (MC30, 40, 60, 75,240, 225, 275, and several solid state variants) are built from two pieces of material, one of which is a prechromed steel sheet. Both are straight brake jobs. The Marantz amps are a folded full box with the transformer cover and are all painted. The Marantzes also had a meter movement, of fairly good spec, and a complicated rotary switch for metering. The Marantzes also have a much more expensive pair of output transformers wound with square secondary wire and a lot of industrial or telco grade parts.

Mc had a better idea also IMO with the MPI separate scope rather than putting it in the tuner.

But before you get too impressed with either, look at the CRT display in an IFR service monitor.

 

The Marantz 2 & 5 power amps were the only units with Telephone grade electrolytics and advertised as such in the magazines and brochures of the day.

The telco caps are oil filled devices in a rectangular shape. Nothing like the consumer grade "FP" cans more commonly seen in consumer gear.

Starting with the Marantz 8, they replaced these caps with Sprague Long Life conventional FP style twist lock cans. True, they are surprisingly long lived, but not telco grade nor oil filled.

I've restored 8B amps, and that switch assembly is a common bakelite wafer device, actually quite fragile. Nothing exotic. Ditto for the meter movement. The Good-All coupling caps are mylar, though, and pretty good quality. I believe Fairchild used them as well.

I'm not knocking down the 8B, not at all. But it couldn't have possibly cost twice as much as the MC275 to build.

 

If they were oil filled, they were not electrolytic at all. Oil capacitors are superior to electrolytics in all performance parameters, but they are large in relation to their capacitance. They are not necessarily super high priced but more than regular lytics. There is such an animal as a "telco grade lytic" although that is not its correct technical term-it offers larger capacitance than an oil cap but does not meet mil temp standards nor is it nonpolarized. Although it is usually a lower voltage device, usually not very much more than 48V, which is the telco battery supply.

I pulled up schematics for the 8 and 8B from a site:

http://www.ys-audio.com/wce/marantz8.jpg

http://www.ys-audio.com/c_wcrut.htm

Unfortunately as .jpgs the detail isn't good enough for me to make out the values.

But from photos elsewhere it does look like the 8 and 8B share round lytic cans and the 2 and 5 have mil style battleship gray oil caps.

So I stand a little corrected, though the metalwork on the Marantzes was certainly no cheaper. I'd also bet that marantz was paying more per hour for assembly than Mc was.... But the only people who know for sure are probably dead.

I'd still very much like to ferret out the factory publication from Marantz on replacing the 8B transformers and the procedures used to optimize the circuit for each transformer.

 

Hello forum
Just my 2 cents newer electronics hi-fi at least is just not built the same. I purchased a yamaha or denon? receiver that claimed 100+ watts. in the 90's hooked them up to a pair of new speakers i bought Bohlender Graebener's planar's, and the sound was disappointing, that was putting it nicely. After trying several different settings etc, I remembered my marantz 2270 from a flea market $15 bucks. Always thought junky spare that looked cool. Hooked it up, and WOW! Music ... rich & clear. Made me think what the ??? So a few things I realized having dis-assembled repaired both new and older stuff, the older electronics is just more robust all the parts are bigger than there modern counterparts. A resistor today is the size of a grain of sand, okay 5 grains of sand. You need a macroscope to work on them it helps. 60's 70's gear resistor is the size of pencil eraser. you could have used your mom's iron to solder it. That goes for all the parts from older gear, larger parts allows more current flow,
less clipping. There's plenty of excellent modern gear also but the price reflects better parts.

just my 2 cents
enjoy the sound
rtl

 

Not my fully restored 2238B.

 

Late reply, but better late than never.

You must have gotten a USED model for $88 because by 1979, the 2220 was already 5-6 years old since they only made them in 1973-74. They retailed for $300 when new.

 

Which is more sought after, Marantz 8 or the Mac 275?