Apollo Valve Amps

[Sonor]

Hello,
Hope everyone is keeping well.
Would anyone be able to help with with recommendations for valve amps to drive the Apollos
Any guidance with any info to improve the sound? eg crossovers caps etc
Mine are the ones with 130 A drivers.
I am new to vintage JBls and would like to learn a little more about my speakers.
Thanks for any guidance help and advice.

[1audiohack]

Hello Sonor!

Welcome to Lansing Heritage.

I have very little valve / tube experience to offer, sorry.

I do have a friend with Apollo's that runs them with SAE amps.

More than anything I wanted to offer a welcome.

Surely someone will chime in with experience.

All the best.
Barry.

[speakerdave]

I'm not an expert from the technical standpoint, but will venture that the relevant feature of tube amps for woofers designed in the tube amp era is the transformer output, not the tubes. That is, the impedance relationship between the amp and speaker, aka damping factor. So, transistor amps with opt's such as some McIntosh would serve just as well. Any good quality amp from the tube era that has been thoroughly gone through and restored should do to fill that category, as well as more recent examples. Other than that, it is just your preference. As Barry has pointed out, some listeners find regular transistors amps work just fine for those speakers.

[Mr. Widget]

Welcome to the Lansing Heritage Forum.

Regarding "what you have", if the woofer is the 130A, then you must have the 001 system which comprises of that woofer, a 1200Hz crossover and a LE175DHL. This was a very early design. It offers very high sensitivity so you can play around with virtually any low power tube amp you like.

Additionally due to the high sensitivity of your woofer, it has very little XMAX and a fairly high FS. This translates to not much deep bass and even with equalization you will be limited as to what it can do down low before you damage it. For the high frequency driver, it was the lower cost option of the JBL compression drivers so it doesn't extend as high as the LE85, or have the very dynamic midrange capabilities of the 375.

All that said, you can always add a super tweeter for more highs if you feel they are lacking and you may want to add a subwoofer if you feel the need for deeper bass. Then again, if you use a tube amp that has rather weak control of the woofer (low damping factor) you will get a full sound that may satisfy you in the bass department and you may be able to use a bit of treble boost to get the highs back.

Whether the speakers are right for you or not is a personal choice thing. The 001 system was a very good system in it's day and can still bring a lot of joy if you understand what you have and don't have unrealistic expectations.

Lastly, on the crossover. They are probably the weakest link in the system. A simple cap or wiring upgrade will buy you very little, but may make you feel like you are doing something. I would replace the crossovers entirely.

Play around with your Apollos and let us know how you do.


Widget