Mac Attack! McIntosh MA-5100 Integrated Amplifier McIntosh MR-67 Tuner JBL Studio 590

Mac Attack! McIntosh MA-5100 Integrated Amplifier McIntosh MR-67 Tuner JBL Studio 590

By mrgoodsound 

Editor: I really knew relatively little about mrgoodsound when he came on board. After some exchanges, I became more and more surprised by the scope of his vintage interests. I am delighted he has started to write about his system and vintage equipment. I have a lot more to comment on McIntosh etc, but I'll leave that to the comments section.

12" Stentorian HF-1214 drivers

A Transitional Phase

I am currently stuck in loudspeaker purgatory. I have 3 DIY speaker projects on hold for one reason or another, 2 or 3 more DIY speaker ideas, and a shortlist of (vintage!) commerical loudspeakers that you just don't see come up for sale every day. The desire to rid myself of my current inefficient modern tower speakers for high-sensitivity, low-loss, alnico-magnet loudspeakers from a bygone era is at the top of my mind these days. Even stronger still is the desire to continue to enjoy music every night, which means making the best of the acoustic system I currently have.

JBL Studio 590

As to what I currently have, the Studio 590 is still enjoyable. It is a 2.5-way design using a compression driver in a bi-radial horn and two 8" woofers. The Studio 5 series has been around for a few years now and was reportedly Greg Timbers' (JBL Everest, JBL 250Ti) last design work for JBL before his departure. It's primary shortcoming is the nature of its crossover design, the complex filter networks and attenuation required to match the horn-loaded compression driver with its lower half. Efficiency is lost, electrical (and musical) energy is converted to heat and the critical middle frequencies shy away from the spotlight or a chance at expressiveness until the volume is increased. The sound is very modern and 'straight-up', and experiments with well-designed high-power push-pull pentode amplifiers showed that solid-state amplification is still a necessary evil, despite a published 90dB @ 2.83V sensitivity rating.

Still, this model is available factory direct and often on sale for about $1,000 US a pair. For this price, I find them recommendable and superior to the large majority of commercial loudspeakers at this price point. Much has already been written about these speakers online and I will not go into too much detail other than to say I like them but yearn for better. The best review I found, complete with measurements, was published in Aussie mag AVHub here.

McIntosh MA-5100

I browse local audio classifieds daily, for opportunities to acquire desirable vintage equipment, although this often gets me into cases of buying things I don't actually need in any way. This amplifier was one of these purchases, but I am fairly pleased with it. I picked it up along with a MR-67 tuner from a gentleman who had lived with them for over 20 years. He was a retired combat veteran and could no longer enjoy the equipment in his living situation. I felt rather bad, but he expressed satisfaction that both pieces were going to a good home.

My new (to me) MA-5100

The MA-5100 is a full-function integrated amplifier with phono section and 45 watts per channel. It was manufactured in 1966 and was one of the early solid-state units offered by McIntosh, based on silicon transistors. Firstly, my bias against McIntosh. I think modern (post 1979 production) McIntosh equipment is a travesty. The quality (I speak only of internal construction and circuit design for integrity of sound, not fit & finish) has only declined over the years, and it is to a point where they produce amplifiers that look more like computers than audio equipment inside, not to mention the frequent re-issuing of classic models that perform worse and worse than the original. Misguided engineering via over obsession with specifications (1 kilowatt amplifiers!) to produce products to appeal to those who wish to show off or are truly on the path to audio hell. Like present-day Klipsch, their sales are sustained on brand power and marketing only.

The subject of today's article is from a different era, and I am fond of McIntosh gear of the 1960s and prior. The MA-5100 is gorgeous, especially with its wood grain enclosure and original fascia lighting. It has tone controls, loudness contour, old 'LP' phono equalization, and two phono inputs; all features which I use and appreciate. The sound has traces of harshness associated with early transistor equipment, but despite this it plays with great immediacy and presence. This is only once a critical volume threshold is reached, as is the case with nearly all solid-state amplifiers. However, still impressive, and perhaps the hallmark of McIntosh equipment from this era. Tonal and timbral quality is there, and the sound is not awfully washed out like modern McIntosh amplifiers. It can be used to enjoy jazz and classical. The MA-5100 was an 'entry-level' piece and can be found for reasonable prices today. It is not autoformer coupled on the output, but this is frankly an unnecessary feature,  unless you advocate the use of Wilson speakers with 2 ohm impedance troughs.

McIntosh MR-67

The MR-67 tuner is a piece I have wanted for a while. Yes, I still listen to FM, frequently so. In Toronto we are fortunate to have many great stations still to enjoy classical and jazz music. It is a tube tuner and an aesthetic mate to the MA-5100, although their production was a few years apart. Even with a simple copper wire used as an antenna, reception is very good, and the local 96.3 Classical FM can be enjoyed. I prefer to listen to FM in mono as the sound is even more immediate and present, and without multiplexing the signal path is technically shortened. A good broadcast with this tuner sounds warm and inviting, even the commercials sound good.

For a classical novice, FM is a great way to not only hear new pieces, but learn more about them. In between or before playing a piece, the radio host will often give context to the music and who is performing it. I keep pen and paper handy while listening and write down the times when hearing something I like, then look up what was playing on the station's website later.

A tuner will remain a mainstay in my system for background listening, to provide a constant signal for warming up or breaking in other components, as well as when I come home from work too tired to think critically about what I want to listen to. I love this piece although I forsee myself replacing it with a Scott 310E if the opportunity presents itself. The Scott is nowhere near as pretty, but is on another echelon of FM quality compared to any McIntosh tuner. Unfortunately, good examples of the Scott are getting hard to find, and command high prices.