Yes,they are quite different.Both are excellent amplifiers.The big drawback to the otherwise outstanding XL-600 is the cooling fan.If you would like to talk more on the subject,give me a call.
I'm not sure about replcing the fan.It would solve the problem for me.I have always been aware of the fan when it runs at lower listening levels/during quiet passages.Other than that,I think the XL-600 is one of the greatest amps ever made! It has a big,dynamic,natural sound.Brass sounds like brass,piano sounds like piano.I get much of the same character(w/o the fan)in my current favorite--Muse model 160.
Even though the XL-600 is very powerful,it is not great into tough loads(Like Infinity Kappa 9).The 9505 is much better in this regard.
It was nice speaking to you(until we were cut off).I have not heard the VS336,but am a fan of Boston Acoustic Speakers.For a mass market speaker company,they always gave you alot for the money! I owned the VRM-50's and thought that they were very nice bookshelves,but a tad forward/bright.One of my early home theater set-ups was the micro 90 system,which used the VR tweeter and gave the user a touch of high end at an affordable price.That system still lives in my son's bedroom.I would think that most BA speakers would be easy to drive and that an XL-600 or 9500 would be overkill.An XL-280 or a 9300 shold be more than you need.The 9300 was a very sweet sounding amp.Like the 9500,it was Stereophile class B recommended. I believe that the reviewer actually preferred the 9300.The Hafler P3000 came after the 9300/9303 and was also a great sounding transnova amp.
Sorry about the disconnect on the phone. When I had the Boston Acoustics A400's I found them very power hungry. I had them Bi-Amped with the XL-280 and found they sounded even better with the XL-600. Overkill yes but they sounded very sweet and needed a lot of power. I was also in my early 20's at the time and pushed them very hard.(Blew a few speakers back then). I don't know about the VS336 but I imagine it needs power as well.
I had a pair of Acoustic Research speakers I hooked up to my XL-600 back then. I don't remember the AR speaker name but it had four 12 inch woofers on each speaker. WOW. XL600 was clipping(I believe) at very high volumes. The sound would go flat or something like that. Not sure not an expert.
What is a Stereophile Class B rating?
Stereophlle has an annual recommended components list.Class "A" is for spare no cost ,best in world performance.Class 'B" for outstanding performance,but not the very,very best.Class C recommended components are still quite good,but with trade-offs that are a result of price point compromises.Class "D" recommendation is reserved for budget products that outperform their peers and come close to the high end at usually a significantly lower cost.
The Hafler 9500 and 9300 were either the lowest priced Class A or I believe Class B recommended amps from 1993 until 1995 or 1996.
Home Theater Review says(about the VR 336):sensitivity rating of 87dB into a benign eight Ohm load, making it ideal for receiver-based home theaters or integrated amplifier-based two channel systems."While it is always better to error on the side of more power,a 9300 should do quite well.
Well, for anyone interested. I finally got in a XL-600 amp to compare to the 9505 Model. The XL-600 is Much better. Richer, Fuller sound. As well as the bass being much tighter. The 9505 just couldn't handle the Polk Audio Rti-A9 speakers that are rated at 250 watts a channel and 500 peak. After listening to 2 songs with the XL-600 my girlfried says wow that sounds a lot better. She knows very little about audio and didn't even know what I was hooking up. I was going to bi-amp the Polks but I don't feel I even need to now. Amazing the amp was made about 25 years ago now.
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.
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)
I'm guessing you didn't check out the link that I provided.
(F)ast (R)ecovery (E)pitaxial (D)iode It's been my
experience, that their being substituted for common bridge
rectifiers, eliminates much grain/noise from gain circuits,
resulting in a more natural presentation. Regarding the
leaving off of the amp's top: I suppose it could be dangerous,
if there are those around that might place their hands in the
amp. I'm not faced with that issue. If I were; I would use
stand-offs(about 1/2") and longer screws to reattach the top.
No, I looked at the link and it didn't mean much to me. I live in the Philippines and my biggest challenge at the moment is finding someone who will repair the Amps using my parts. I went to a chain shop yesterday that was recommended but I have to use their parts. Who knows what they would be.
I appreciate your input. I should be hearing back about a different tech recommendation today.
Wish I knew someone competent, and close to you, that I could recommend. If you lived in Indiana; I'd help you myself. In reality; one only need be able to use a screwdriver, to replace the filter capacitors(in the 9505). No soldering involved. Just disassembly/reassembly. It's unfortunate that Rockford has stopped supporting the Hafler line, with replacment parts & service. Hope you get your tunes restored, and soon.
Mainly; a greater sense of dynamics, faster/more tuneful low-
end, less noise(some call it, "blacker background) and a
smoother/more detailed top end(not to say muted, recessed or
falsely accentuated in any way). They also allow upgraded
fuses and PCs to show off their benefits more obviously.
There are a few electronic manufacturers that offer them, as
an upgrade. ie:
(http://www.rogueaudio.com/The_Magnum_Series.htm) Of course;
upgrading your filter caps adds to the improvement too.
Parts Connexion also offers these rectifier PCBs, so you can
more easily do a discrete HEXFRED or Schottky bridge: