Trying the minimalist route: PROTON AI-3000 II All-in-one Stereo Reciever and NOTHING ELSE!

Gentle reader,

Yes, it has been a long time since my last post. I've been incredibly busy remodeling our house. So, busy, it seems like that is all I ever do.

As you know, I have become a PROTON audio fan since buying my first D540 integrated amp some time ago. In fact, I've been compiling images from various sources of the many home audio equipment they made back in the day.

One component in particular has intrigued me. They made an all-in-one stereo: Stereo receiver with the usual AM/FM tuner, albeit, this tuner is supposed to be incredible. Plus they built in a fine CD player AND a cassette deck too. All in one, well not compact, it's quite large and heavy, but it is less than the standard 17" width.

In fact, they made three models, first was the AI-3000. It was made from 1988 to 1990 and retailed for $1250. Making it the most expensive PROTON product one could buy. It included two matching speakers. But I have read the speakers aren't that good. Next came the AI-3000 II, although my Orion Audio Blue Book also lists an AI-3000 IIS as well. Whether that is a typo, I do not know, but no information was found on an "S" model. The II came out in 1991 and was made for two years. The book lists a third called AI-3200, which were from 1992 to 1994.

Almost every photo of these I have seen, the door that flips down is missing. The few, that have them, the sellers wants a LOT more money for. For a friggin' piece of plastic?

This is actually the second one that I bought. The first arrived having been dropped en route and the CD player wasn't working. Full refund allowed me to buy the one above which is an improved model: Much better CD transport and some added box on the back where the earlier (by serial number) one has a blank back panel. A riddle to as to what lurks within the mysterious back box which can been seen further down in the article.

One thing I wish was different, the cassette deck is auto reverse. Much more convenient for sure, but once you've heard cassettes on a 3-head deck, there's no going back.

As the seller stated, everything DOES work on this one and I have been giving all the circuits a workout.

Here is what the system looked like before I started disassembling it last night:

TWO and a half systems crammed into the rack with TEN speakers available for use. It had gotten crazy. You may recall my quest to reassemble my first stereo from 1976? That plus the addition of a mono channel is the extra system and a half. BELOW is what it looks like now:

HUGE difference, wouldn't you agree? I tell you this, that rack is a whole lot easier to move now! Below are all the components removed, plus in the stack is the other AI-3000 II:

TOP to bottom are: OPPO universal disc player, PROTON preamplifier, TDK CD recorder, which I have yet to use, Nakamichi CD changer, which is AWESOME, PROTON D540 that acted as the mono power amp, PROTON AI-3000 II with the bad CD player that was NOT part of the system, Dynaco power amplifier and the 12" subwoofer that I used to use with the smallest speakers at the top of this electronics totem pole.

I converted the photo above to black and white for fun.

Speakers above, both I have previously written about. They are formerly Radio Shack models called Minimus 7W and Minimus 11. All R/S components are long gone. Well, OK, the woven Kevlar woofers are R/S units from a pair of Optimus speakers that have a huge cult following.

Above are all the various cables not being used at the moment: Three PANGEA AC-14 power cables, one for the subwoofer, one for the Dynaco amp and the darker one is an AC-14SE which is for the OPPO. Next are the Monster Cable Z-Series jumper speaker cables that I have removed from the path from SWTPC amp to Dynaco PAT-5 preamp's speaker selector circuit. Beneath those are the smaller BLE Design braided speaker wires, beneath those are the Seismic Audio speaker cables that I bought to get the 1/4" mono plugs for the SWTPC amp. Next is the pair of digital (one optical, one coaxial) cables that linked the OPPO to the TDK CD recorder. Beneath those are the thick Radio Shack cables that I found and were the analog input cables for the TDK. Next are the 1/2 meter Liberty Cables Z-500 THX Certified cables that were PROTON preamp to Dynaco power amp leads. Beneath them are the Monster Cable (don't remember the model name/number) that served the OPPO and Nakamichi's output to the preamp. Last pile are various other RCA interconnects.

NOW, here is the improved connection intimated above from SWTPC amp to Dynaco preamp:

The foreshortened Seismic Audio cables send the signal to the PAT-5's Amplifier input 3-way binding/banana terminals. The "A" speaker terminals only have the lamp cord mono speaker wire in the left terminals. The Monster Cable Z-Series speaker cables are in the "B" speaker terminals and lead to the AMAZING Dynaco A25XL speakers for stereo duty. And YES, you do NOT see the phono cable plugged in, because it is too short to reach while the rack is this far away from the wall.

This arrangement is so much simpler and more elegant than the monstrosity I had set up prior. WHAT was I thinking? 

Below is the rear of the PROTON AI-3000 II. I added the speaker selector switch box from the previous kit to this so that I can power two sets of speakers with the 3000. The Klipsch KG4s in the listening room and the Cerwin-Vega LS-12s in this room. I've been listening to the C-Vs all day as I've been editing photos and typing this. I think they sound fantastic. Maybe some, or perhaps most Cerwin-Vega speakers are Mid-Fi,  but the LS-12s are Hi-Fi.

The AI-3000 II has two RCA inputs: PHONO and VIDEO, plus PRE-OUT! Yes, my faithful readers, it can also be used as an all-in-one PREAMPLIFIER! Who knew? I have not tried it and wonder if somehow the unit is designed to turn off the power amp portion is plugs are inserted in those terminals? 

YES, there IS the mysterious added on box I told you about. There is some lettering I can see, but it yields no clues.

SO, how do I like the AI-3000 II? Very much indeed. Of course I am using the speakers and cables that I have been using prior, and since those were powered by products from the same factory in Taiwan (the 1990's rebirth of the Dynaco brand, PROTON and NAD were all made there) the sound is quite similar. Very dynamic from records, CDs and even cassettes. 

Now, get this: The maximum output per channel is 22 watts! Yes, that is IT! But remember, the SWTPC amp from the 1970's also only puts out 25 watts per channel. The key to the extreme volume without distortion is the speakers: The Klipsch KG4s and Cerwin-Vega LS-12s are extremely efficient. The more efficient (measured as X decibels from 1 watt (or 2.83 volts) at one meter in an anechoic chamber) the less amplifier power is needed to play very loudly. This is vital for classical orchestral music as the music has tremendous range from quietest to loudest passages.

MY plan is to enjoy this simplified stereo for as long as possible. Eventually, I am going to want to record CDs for instance or listen to SACDs and HDCDs. But in the mean time I plan to enjoy the simplicity of the PROTON AI-3000 II All-in-One receiver.

One problem was discovered in this endeavor: The Dynaco PAT-5 preamplifier's LEFT channel PHONO input has ceased to work! I tried the LUXMAN turntable with the 3000 and both channels work. So, it is the PAT-5 at fault. Sigh. ANY DYNACO fan out there know how to fix it?

Based upon my findings of the one Phono channel input not working, today (the 29th) I pulled the rack out again and disconnected the RCA cables to and from the PAT-5. I moved the power cord for the SWTPC amplifier to the Adcom ACE-515 power conditioner beneath it to the one below the JVC cassette deck. I leave the ACE-515 on the right off, so the PAT-5's passive Speaker connections and switch is still usable. It is not using any AC power at all.

Thanks once again for looking,

Scott

October 26, 2017