Hafler XL600 Vs Hafler 9505 Much difference?


Hello all, I am new here and still learning to navigate the website. I have been out of audio for a number of years. I had an old Hafler XL600 years ago and really liked it for the price. I am thinking of getting into audio again and am considering purchasing either an XL600 or the newer Hafler 9505/9500. I have read there have been a lot of improvements in amplifiers in the last decade. Is that true? How much difference is there in the amps I am refering to? Would I notice a difference between the XL600 and the newer amp? I hope to purchase Boston Acoustics VS336 speakers to go with this.
Any info would be helpful.
Thanks
sundriednm
The XL-600 is stock. Did some more listening. The XL-600 has a great sound stage and imaging. Better than the 9505 in my opinion. BUT, after listening for a couple days, the XL-600 was very tiring on the ears. Lot of fatigue. That doesn't happen with the 9505. So I bi-amped them with the 9505 on the high end and the XL-600 on the woofers. Sounds excellent. Amazing and not tiring. The speakers were meant to be bi-amped. Sum it up. NO way the 9505 has the power to push the Rti A9's. Bass was very very loose with the 9505 alone. I thought it was the speakers. It was the amp.
It is my opinion that the XL600 and the 9505 do have similar sounds. Only got to audition the 9505 one time though and it was not on long enough to really get warmed up. I own two DH220's, one DH200, one XL600 and a Pro5000 and a DH110 preamp. Been buying defective units and fixing them in my retirement. Just recently got the XL600 and it does sound nice and smooth, IMO. However, strangely I find that the Pro5000 seems to have the most clarity of them all. A good recording on the 5000 sounds like it is taking place right in the room.
Well, my XL-600 is having problems in one channel now, so I will be taking it to a repair shop. Maybe I will buy an upgrade kit for it as well. Hopefully, the Amp sounds more like the 9505 then?? Thanks for your feedback.
I have never heard a Pro5000 before. I will check out prices on that.
Thanks
Chances are good that what you're hearing as a, "bass problem" with the 9505, is a case of expiring power supply filter caps. I've been using mine to power the bottom of my actively bi-amped system, for a number of years. My filter caps went south, about three years ago(symptoms appeared earlier, of course). The differences would be much more noticeable(across the board), if the amp was used full musical bandwidth. Especially given that you seem to enjoy cranking your tunes. These made a world of difference, but you have to leave the top off the amp, as they are slightly taller than stock: (http://www.digikey.com/product-detail/en/B41456B9229M/495-4228-ND/2269437)
Should have mentioned; those caps are slightly(10%) over the stock uF value, very low ESR and long life. You can further improve your 9505's presentation, with a pair of these(easy to install) FRED bridges: (http://datasheet.octopart.com/VBE17-06N07-IXYS-datasheet-143416.pdf), higher quality binding posts and RCA's, all of which can be gotten from Michael Percy: (http://www.percyaudio.com/Catalog.pdf)