Cheap Tube Amplification- the Allied 333/Pioneer SX-34

Some other vintage options on the table are to forgo vintage receiver's, such as the Scott 500C (I own a restored one of these, in great condition), which put out 30-WPC.

Receiver's are complicated beasts, having AM/FM/FM Multiplex (stereo), phono preamp circuits. My 500C has 19 tubes and lots of resistors and lots of capacitors...

Both Scott and Fisher made smaller integrated amplifier's that use EL84 tubes and more powerful versions, still in the EL84 family. Other vintage models use compactron tubes, which have more than one tube design within the same tube envelope.

These units a far less complicated and are more reasonable priced, than the larger receiver's. The units are smaller, less expensive and are easier to store and upgrade than the larger more complicated receivers (which have the radio's built in).

All in all, they are more reliable than the receiver's because there is less to go wrong with them.

They will typically have 16-22 Watts of power available to them and can therefore drive speaker's that are 86-87 dB efficient, louder before encountering clipping and having distortion set in.

Here is the listening room of one of our member's, @action pact, who just got a deal on on a pair of Splendor speaker's that were shipped to him from England, these speaker's would retail for just over $2k in the US.

On the bottom shelf, if I remember correctly, is his Fisher X-100 integrated, which uses four EL84, small output power tubes and produces 20-WPC.



As you see, the design is a lot more simple than the larger Fisher type receiver's.



This integrated has tube rectification. The EL34 power tubes are really sweet sounding, they cost a lot less than the larger power tubes and last practically forever. The 20-WPC can drive most speaker quite nicely.

These types of amps are nice if you want a step-up from a lower powered amp, like the Allied 333, for just a little bit more money than the Allied.

 

Having previously owned a Fisher 400, I agree with all of the above. My X-100 presumably has a simpler signal path, and fewer tubes equals less heat in the room (which is important in the summer!). I actually like the more open and lively character of the X-100 better than the warmer, slower character of the 400.

Some corrections to the above:

My tube-rectified '59 X-100 puts out maybe 13 or 14 wpc, not 20 wpc.

My Spendors retail for for $3,195 at Acoustic Sounds; I paid a little over $1400 for a mint condition pair of demos, including shipping from England. Otherwise I wouldn't have been able to own such nice speakers!

 

I am using 12 watts on Revel Performa M22s that are 87.5dB sensitive. Plenty of volume. The Revel 6 ohm speakers appear to be tube friendly and dips only to 4.8 ohms.

 

Those specs are comparable to my Spendors, and my little Fisher has no problem driving them in a small room either.

 

Splendor is a wonderful speaker.

 

The Allied 333 12AX7 long black plate was replaced with a Mullard 12AX7 round getter long plate for an increase of performance. The tube was more clear and every instrument & voice stood apart better. It produced a remarkable sound stage. Then, later I tried Mullard 12AX7 square getter long plate. These are very expensive tubes. An additional minor, but noticeable increase in performance was noted and with this tube. So far no other tube type amps outperform the Allied 333.

 

The Allied just outperformed a rebuilt Scott 272 amp. I guess it will take a pair of Audio Note Conqeust amps to outperform this K40Y-9 rebuilt amp (receiver).

The amp structure in the Allied is like I never seen in an amp. It only has one stage of phono/preamp amplification. All others use at least two stages. This amp (receiver) should not have enough gain for a MM cartridge, but it does. Perhaps such a direct audio route to the power tubes is superior.

 

I changed my mind, stay with All Russian K40Y-9 capacitors. Polypropylene type are ok in the tone controls.

 

Seems I dont have permission to PM just yet... New member here and first post hello everybody! (I didn't see the introduction thread). Fledgling collector/listener on a budget. Not much of anything special yet aside from I do have one of these and was wondering if you might be able to go over it for me. Picked it up pretty cheap some years back. I'm willing to put another hundred or 2 into it. Admittedly it makes a low buzzing from the "big cap area", and has some channel imbalance. But I did like the type of sound it was producing aside from the issues. Using some modded fostex t50rp headphones. Nothing special for actual speakers just yet. But anyway was wondering if I could maybe send it your way for some fixing and upgrading one of these days.
Not really a vinyl guy. you could skip that part. Not really a radio guy. you could skip that also. Just line level (cd or dac) audio mostly. Or would I be better off just looking at that yaquin perhaps...

 

Well, a rebuild is close (but less) to same cost as a Fisher or Scott vintage amp. $450. You would have no extra cost buying a Yaqin MC-13S and selling the Allied 333. You do not need a phono preamp that the Yaqin does not have due to not owning vinyl.

 

Oh whoops. I thought I saw (about $100) posted above somewhere. And then with the repairs needed I was hoping more like 200. Must have misread. My bad.

 

Apologies for my initial shock and reaction. I'm still considering maybe sometime here...