Importance of Amplifier versus Preamp?

Thank you all of you Gentlemen and Ladies for the insight.
I feel like I am learning a lot about this magical world!
Here is my equipment:
amp: SAE 2401, vintage
preamp: Nikko Beta 2 , vintage
Sony TA77ESD, vintage
Yamaha CD300S cd player new.
cables from Blue Jean cables.
I listen to classic rock, blues, some classic.
as far as budget , I am looking at maybe another 1500.
All advice is much appreciated.

I just purchased , used , a Sony ta 55e77s, and I have a Nikko Beta 20.
What would you suggest that is vintage, from 1985 through 200 that would be good.Thanks.

Almarg,
here we go: SONY TA-E77ESD is my preamp working with the SAE 2101 amplifier.Sorry about that mistake.
I just bought another amp:Sony TA-E330ES for my office.
I probably will pair it with the Nikko Beta 20.
What bookshelf speakers would be a good choice? Thank you kindly.

Therefore, after all those advices, the quandary becomes: I will keep the Sony and the SAE ,but I need to upgrade the speakers.
What would be good floor standing used speakers for $1000?
Should I go vintage, or current? Hum.........

therefore the question becomes: for a limited budget, I have looked and purchased vintage equipment because the idea was that the vintage equipment was better engineered/constructed that a lot of equipment made today, for 1/10 of the price of today equipment.
As far as the polk speakers,should I get other speakers? what do I need to look for. Just so everyone remember,at my age, my auditive range is probably 90 % of what it was when I was 20, so my ultimate goal is a sound that is clean, with an emphasis on mid range, and just enough bass to be balanced. Hope this make sense.
Speaker specs: Monitor 75 T/•1-inch (25mm) silk/polymertweeter/•Four 6-1/2-inch composite drivers/frequency response:30Hz - 25kHz /
thank you for your input.

After reading some comments on amplifier, I really wonder what mechanical/electrical/audio miracles have been performed , knowing the fact that the laws of Physics are still the same as they were 20/30 years ago, metallurgy has not come up with new alloys, to justify the cost in ten of thousands of dollars. As Mr Carver demonstrated, by building an affordable amplifier, of which the sound could not be distinguished from an extremely expensive name amplifier that was being compared to(mid`s 70 )!
The fact also remains that the human auditory system is very limited in scope, unless your name was Beethoven, or Mile Davis,for example. Just wondering.....So if I was able to spend 5/6 grands on an amplifier, I would probably buy a Carver amp...I can already feel the wave of outrage from all the AUDIOPHILES coming at me....OHLALA!

Zd542
I think that all the answers were great!
But you lost me with the respect "innuendos".
So sorry to have offended you.
Just so you know, most of the music I have listened to sound warmer on older equipment.
Here is an excerpt from Lincoln Gray, Ph.D., Department of Communication Sciences and Disorders, James Madison University on neural auditory system:
The Range of Sounds to Which We Respond; Neural Tuning Curves

Our absolute threshold, the minimum level of sound that we can detect, is strongly dependent on frequency. At the level of pain, sound levels are about six orders of magnitude above the minimal audible threshold. Sound pressure level (SPL) is measured in decibels (dB). Decibels are a logarithmic scale, with each 6 dB increase indicating a doubling of intensity. The perceived loudness of a sound is related to its intensity. Sound frequencies are measured in Hertz (Hz), or cycles per second. Normally, we hear sounds as low as 20 Hz and as high as 20,000 Hz. The frequency of a sound is associated with its pitch. Hearing is best at about 3-4 kHz. Hearing sensitivity decreases at higher and lower frequencies, but more so at higher than lower frequencies. High-frequency hearing is typically lost as we age.

In conclusion, no I am not an expert,and I am cognizant of that fact, however, like you said, I read a lot. And thank you for humoring me as well.
Thank you for taking the time.
Respectfully,
Long live Rock and Roll!
Good bye.

Almarg
thank you kindly for the "teaching moment" about Mr Carver.
Much appreciated.
Rockanroller.