Sony STR 7055 Receiver

This beautiful, mid 1970's vintage Sony STR 7055 receiver was acquired yesterday. The STR 7055 was the second highest top of the line in Sony's receiver, bettered by the STR 7065 at that time.

This unit is in mint condition for being 40 years old and needed little cleaning to make it shine. The fuse type bulbs for the face plate need to be replaced and that is about it. While it is opened up I have cleaned out the pots and switches along with the decades of dust.

Vintageknob.org has a more info on the history of this receiver along with all the specs.

From what I have read the unit is conservatively rated at 35WPC, 45WPC at 1K hertz into 8 ohms and 55WPC at 4 ohms with dynamic power of 200 watts at 4 ohms.

I got a chance to listen to this unit for a brief period of time last night and this unit sounds phenomenal. Further searching the interweb, some have compared this model to early Marantz receivers and Sansui  amps. There was even some postings that Sony had their eyes set on MacIntosh amps when building this unit.

The sound is wonderful, full and warm like all units that you would expect from this era. I believe this Sony will be in use for a long time in the sound room.

EPI M100 Versus Mirage 450 Shootout

Up next is the EPI 100's which won out against the late EPI T/E 100 plus and the Acoustic Research AR15's. How are the legendary EPI's going to fair against the Mirage?

Fit and finish: The real wood veneer of the EPI wins hands down against the vinyl veneer of the Mirage 450's. The internal box of the Mirage does have one piece of bracing just above the woofer which helps the front baffle resonance.

Both speakers got a new foam job and recap of the crossover. The EPI's are a 1st. order crossover with a 10uf cap to the tweeter and the woofer rolls off naturally. The Mirage has a 8uf cap 2nd. order crossover for the tweeter and a first order crossover for the woofer.

I like the modern looks of the Mirage but prefer real wood veneer....These two are tied.

Sound: Both speakers have a similar sound signature and both have tight articulate bass. the EPI 100 goes just a tad lower and has a tiny bit more weight to it but both are pretty close in the bass region. Bass lines on bass guitars are easily distinguishable, there is good weight to lower piano keys.

The mid range seems to be a bit smoother with the EPI 100's narrowing the sound stage to a space in front of you. The Mirage tends to expand out the sound stage a bit more. But more or less the mid range is pretty close.

The treble region is where the Mirage takes over. The dome tweeter reveals higher detail in the cymbals and other percussion instruments. For my ears I can just hear a little more of the drum sticks hitting the cymbals.

My conclusion is both speakers have strong points and week points where the other one does not. They are both worthy entry level vintage audio speakers worth picking up. I like the real wood veneer and the deeper bass of the EPI but I also like the looks of the Mirage and the detailed high end of the tweeter.

Both speakers are awesome.

In the end I feel that these speakers are a tie and I could live with either pair of them.

Audio Technica AT-701 Stereophones

A cool pair of vintage Stereophones came my way this week, Audio Technica AT-701.

These stereophones seem to be about a mid to late 70's vintage and in good shape. On first listening impressions the mid range and highs are very nice, as is the stereo imaging. The bass region is a little light but not to bad when used with a loudness switch or a boost in bass.

The fit is very comfortable and the coiling cord stretches for at least 9 feet.

Pretty cool cans for the head.

The brochure line I like the best is the cups that add severe peaks in response.....Um, I don't think that is what you want to say in an advert!

EPI M100 vs. Acoustic Research AR15

Up next is a classic shootout between two speakers that probably competed against each other in the mid 70's the EPI M100 and Acoustic Research AR15.

Both speakers are two way with 8" woofers, one with an inverted dome tweeter and one with a dome tweeter, both are acoustically suspended systems and the cabinets on both are real walnut veneer. Both speakers are crossed over at 1800hz. Both speakers also got new caps and the veneers were sanded and re stained.

I will start he shootout with aesthetics, both speakers are well built with stunning real wood veneer. I painted the fronts of the AR15's with a piano gloss black which gives it a nod in appearance. Also the insets for the woofer and tweeter on the AR15's are better as the drivers sit flush mounted.

The internals are similar in design but the AR15's have a 2nd. order crossover with a 0db/-3db/-6db level switch for the tweeter on the back. The EPI is a 1st. order crossover on the tweeter alone.

I would give the nod to the AR15's in the aesthetic department.

The sound is where the meat of the matter is.

I  had an extensive listening session between these two and here are my thoughts. The EPI once again has digs deeper into the bass region giving the speaker a fuller richer bottom end something the AR15's just can't reach. From the bass region to the lower mid range the EPI's have a smoother transition. I find the EPI's smoother throughout the mid range right up into the mid treble range, this is where the Ar15's take over.

The dome tweeter on the AR15's obviously extend higher and give off a much more spacious stereo image with more detailed revealed in the material. The Ar15's also give off the airiness sound that surrounds you when listening to the music, where as the EPI limit on the upper regions does not throw off the same airiness.

The sound stage and imaging was a little closer together with the EPI's where as the sound stage and imaging was much more expansive with the AR15's.

I found the EPI's to be a bit more efficient than  AR15's. I had to set the tweeter on the AR15's to the -3db setting or the AR15's where just too bright for my room. Perhaps the design was to over come the heavily shagged carpet and drapes of the seventies.

When listening to George Winston's Autumn, I found the piano notes weightier with the EPI's and less shrill. This CD is a great source for finding the resonance of the tweeters with certain piano keys. The AR15's could at times  be a little shrill, more so than the EPI's. 

So what is my final impression? These two speakers are very close to each other and I found myself leaning toward the richness of the bass and mid range of the EPI's over the spaciousness and upper detail of the AR15's. I could listen to both speakers for hours on end and have been doing so with the AR15's to date.

These speakers are both excellent examples of the golden audio era, both are worth having a listen to along the path of vintage audio.

The nod goes to the EPI's by a nose.

Next up will be the EPI M100 vs. Mirage 450's.

EPI M100 Vs. EPI T/E 100 Plus shootout

I figured since I have both the first generation EPI 100's and the last generation EPI T/E 100 Plus it would only be fitting to do a side by side comparison on how this model changed over the years. To get a brief history on the EPI story check out the Human Speakers site.

 

To start the shootout I will compare the appearance of both these speakers. The original 100's have a beautiful real walnut veneer compared to the 100+'s oak vinyl veneer. the Original EPI's win in the regard.

The EPI+'s have a wider front baffle in which the drivers are flush, this will help in reducing any reflection of sound waves from the tweeter and helps with the expanding the stereo sound stage. The 100+ are better in this regard.

The build of both the cabinets are equal.

Now for the sound of these two speakers side by side. I found the original EPI 100's to be much tighter in the bass region and they tend to dig deeper giving me a fuller more natural sound. The bass notes where cleaner.

The polycarbonate tweeter of the EPI 100+ gives off a very large sound stage and in doing so comes across quite loud and harsh at times. It is almost as if the tweeter could use a resistor to bring the output down.

The original EPI 100 tweeter is a paper inverted cone which does not give off the same sibilance as the polycarbonate dome does. The sound stage is not as wide and a little more focused than the EPI 100+.

When I do an A/B comparison between the two speakers I instantly find the EPI T/E 100+ speakers fatiguing and wanting me to go back to the original EPI 100's.

Hands down the original EPI 100's easily beat out the last version of the EPI T/E 100+. I could listen to the original EPI 100's for hours on end and never get tired of their sound. 

The original EPI 100's are proving to be a classic timeless speaker design that is still highly sought after. If one had an option to buy one speaker over the other the originals are the way to go.

Next shootout will pit the EPI 100's against the Acoustic Research AR15's, these two speakers should prove a better comparison, stay tuned.

EPI M100 finished

These first generation EPI 100's just got a new lease on life this week. It is amazing how good a pair of 40 year old speakers can sound. I am glad these did not end up in a landfill.

I picked these speakers up from a guy that bought them new as part of his first stereo back in the 70's and I am happy to do a full restoration on them.

EPI 100's are a great speaker design from Winslow Burhoe and a very simple in their execution. The woofer digs deep for an acoustic suspension design and can attack the bass notes fast, the tweeter is crossed with a simple 10uf cap in the first order at 1800hz. The cabinets are well built and have a beautiful walnut veneer to them.

At the ripe age of 40 years old the following was done to bring these awesome speakers back to their youth.

Both woofers needed a re foam, which they received.

New polypropylene +/- 5% caps where installed along with upgraded copper speaker wire.

The speaker terminals where upgraded to gold plated binding post that accept banana plugs.

 

While the driver where out I sanded and re finished the walnut cabinets with 2 coats of Minwax natural stain to bring back the natural beauty of the wood.

All in all this was another excellent opportunity to bring this classic speaker back to life. I have had a few hours of listening pleasure with these original EPI 100 and it clear why these musical speakers have stood the test of time in the vintage audio Renaissance. EPI 100's  are always worth the time and effort and should be experienced by anyone who is into vintage audio.

Mirage 450 sound

I have had a good 24 hours with the Mirage 450 speakers originally manufactured in the mid 80's by Audio Products International or better known as API, the same guys that make Energy speakers.

From what I gather these speakers retailed around $450.00 and are definitely a mid-fi offering.

The speakers are very open in the high end by what looks like a Vifa tweeter, the 8 inch woofer digs decently deep to around 40-50hz. I tend to find I like the tightness of acoustic suspension speakers more than bass reflex models. The mid range is right in the middle, not overly emphasized nor to far back.

Acoustic suspension speakers do not over emphasize the bass region and tend to be a little tighter in the reproduction of bass notes. Bass reflex speakers can have a boomy sound to them.

I really like these speakers I would put them 2 notches above a pair of Mission 700's  but three notches below my pair of Mission 770's.

The Mirage 450's are non fatiguing and a real pleasure to listen too, the sound stage seems just right, not to far back but not surrounding you either. Esthetically these speakers are quite pleasing to the eye.

This project was well worth the effort and I will enjoy listening to them before moving them along.