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Brian
05-11-2003, 09:12 AM
Well, after playing around quite a bit, the Philips preamp is not as bad as I thought it was. Unlike McIntosh where the amp gain controls do best fully opened and still require sufficient voltage to keep the preamp in the optimum curve of the output voltage, the Philips combo does better with the amp gain controls turned down and the preamp pushing higher voltage. The inputs and outputs must be buffered to minimize impedance mismatching.

The preamp inputs don't overload with 2 volts which is the max out of the Philips tuner throught the variable outputs. I used about 1 volt for listening.

I settled on testing with the Smaller Advents which do well in my room as it is. I decided not to use the Klipsch since the speakers are too efficient and I couldn't get the settings where I wanted.

I have been moving the Advents using a Sony STR6045 receiver and they are positions about 3' from any wall and about 18" off the floor to get the tweeters closer to listening position. As is, with the Sony, the sound stage is almost wall to wall and starts in front of the speakers and goes quite deep. The height is from the floor to almost the ceiling (7') but, not too tall with solo instruments. As setup, the Sony/Advent makes for a really nice classical listening system though a better antenna would help I think to reduce the Fm noise base. With the Philips, the bottom to top soundstage stayed while the side to side is now done to the outside of the speakers and the front edge moved back to the fron tof the speakers. Driving the tuner directly into the power amp increased these but, still less than with the Sony. I've tried moving the speakers a bit but there was no position that increased the soundstage.

Soundstage is only 1 thing I look for with, another being instrument placement. Here the Sony took the back seat. With the Philips, you almost felt you could put a marker where each instrument was. Subbing the C28, the soundstage increased but, not to the dimensions of the Sony and instrument placement was not as well defined.

The Philips does not have the authority of the C28. It does have greater detail while resolution in some ways is better and some ways not as good. The C28 delivers the tones from the soundbox of stringed instruments better while picking out what is being used on a cymbal goes to the Philips.

Kettles and cello has more of the attack recognized by the Philips while the C28 conveys more of the tonality. The C28 meanwhile picks up the attack on a triangle better as well as the tonality. Male vocals on either are very close. The is more sibilence with female vocal on the Philips but the voice is - well a bit more feminine.

The C28 gives me the feel that I'm say in the BSO listening while the Philips seems to put me on the banks of the Charles river listeing to the same thing. Lees hall effect, more open and airy.

The phono preamp was turned down to about 2mv and it helped focus and did not have the confused sound which it had been exhibiting. This is the opposite of what I had thought should happen but after rading the manual and realizing the preamp has four (4) independent phono preamps - yes each phono input has a separate preamp so you can run 2 radically different cartridges without having to play the gain reset game as with most preamps. You could even mod 1 for a diferent optimal load if you wanted. The result here was consistent with my other observations.

The Philips requires a bit more time to set up in the system to get the best out of it as I found out. But, once dialed in is better than I initally thought. I suspect the reveiwers back in 1978 of the preamp got so involved with the lights and switches they did not set it up and the resulting reveiw was as close to a neutral comment as I'd read. They spend too much time on the lights and switches and maybe 25% of the space on the sound qualities. If Philips had devoted a bit more to the sonics, the preamp could have been a contender for the very top few positions.

The Philips system as a whole, is very good to excellent. The total presentation is different from a McIntosh and for those who don't find the McIntosh experience to be enthralling should really enjoy the Philips. Even as a McIntosh lover, I find the system, now that it is dialed in better even more impressive. It will become my #2 system moving the tube systems down the line by 1 notch.

For those looking for a budget (I'd estimate the amp/preamp/tuner to reasonably go for aboout $1,000 though, a few total systems have been picked up just prior to the FM shootout for something like $400) high power high quality system, the Philips is a must try. That's about half the going price (and 2X the power @ 8ohms) of my McIntosh. If either AM or FM is important, then the tuner, esecially should be on your short list.

As a side, I'm mating the Sony up with the Advents for a longer term tryout. The presentation with classical is as well presented as even the McIntosh though not competitive from the prospective of individual sonic attributes.

Brian
06-01-2003, 10:52 AM
Well, just got the Advents (10" masonite ring) back from being refoamed and moved them into the Philips system. Synergy better than with the Smaller Advents. The woofer spead is faster with the 10" and as I've said before the amp is a fast amp. The preamp is slower with a result that the 3 work better together than the Smaller with its slower (do to mass) woofer in the system. I'm doing a burn-in for the weekend but when I got them home the first listening showed the improvement and this morning the sound was even better. The initial thought was this is more than good enough to be a main system. I'll see over the next few days if I'm left with the same feeling and if the smallness of the Advent could be lived with long term. Remember, I'm used to full range electrostatics and the big Bozaks so the Advents are small speakers and have a smaller sound than I am used to. The preamp does dial in nicely to them and is a good match. It may be the preamp which I thought was a weak point just requires a better matched system to show its stuff off and I may have found it.

Thatch_Ear
06-01-2003, 09:45 PM
Sorry, but the only identification I found in your great review was for the McIntosh C28 and a Sony reciever. Would you tell us what the Phillips was? Seems like great gear and I ought to go give it a listen.
Thanks

Brian
06-02-2003, 05:20 PM
Sorry Thatch,
The preamp is the 5721, power amp is the 5781 and the tuner is the 6731. They are commonly referred to in their silver faced numbers as the AH572 preamp, AH578 power amp and the 673 tuner.

Thatch_Ear
06-03-2003, 08:38 AM
Thanks much. It is about time to go out and do some listening and one of the places I go handles Phillips, so I thought I would check them out.

Brian
06-03-2003, 07:30 PM
Thatch,
These are vintage units from the late 70s. Seems there were a number sold as systems and the 3 pieces do come up as a set on eBay and privately. The tuner was #3 and now #4 on the tunerinfo site out of some 38 tested to date with the Mc MR78 in 36th place. The AM section of the tuner is amazing sonically. It is a REAL AM tuner, not what is in most units. I am keeping it in the main system just for the AM (by using the 2nd set of tuner outputs). The power amp seems to have a quiet following using them in multiamp (bi-amp) systems and @210 watts rms/chl into 8 ohms is clean and runs cool. The preamp seemed to be the question. The press at the time seemed to think it was overpriced because of the map display and capacitive switching. In reality the unit was just ahead of its time. The writers were so interested in these bells and whistles they all but forgot to look under the hood and actually seriously listen. I fell for this at first but after settling down and getting the system set up found the preamp to actually be maybe only weak in that it may compress the signal a bit when playing the same signal directly into the power amp. For an lp lover, the phono preamp with its 4 phono preamps (2 pair) each individually adjustable really means you can run 2 really different cartridges and custom set the preamp for each rather than a single preamp with a switch between 2 inputs. I've listened to the phono sections through the tape outputs directly into the power amp and the phono section alone is worth the price of the preamp (especially at the bargain pricing they are popping up on eBay for). If you have a dealer with a set you should give a listen.

Thatch_Ear
06-04-2003, 06:39 PM
Thanks, I am not up on Phillips and thought you had something that was new. I recently purchaced a Phillips SACD player and was going to look for these componants next time I went in that store. Man would I have put my foot into it!!
:eek:

Brian
06-24-2003, 07:44 PM
Just changed out the interconnects (don't know the make of what I was using or age) for a new set from Rat Shack. These are the gold plate av cables with the separate ground wire. Left the ground unattached. Have let them "burn-in" for the last few days and now in comparing the tuner through the preamp and bypassing the preamp and going directly into the poser amp, the preamp is not exhibiting the slight compression I had previously heard. On CD similar result now. Guess the cables were a limiting factor that I attributed to the preamp. I've now cycled out all my cables for the Rat Shack and find them to work well. As for you guys who have to have pure vintage, anyone want some original KLH model 41 reel to reel tape deck interconnects. These have 90 degree ends and an assortment of other vintage interconnects? Great addition to keeping that vintage system all vintage.

Thatch_Ear
06-26-2003, 09:36 PM
You might try attaching the ground wire to one end only and see if a floating ground does anything. Better wires do make a difference, glad to hear you have improved on the great sound you had.