[herroyuihk]

I think the best of 12au7 are Mullard 12au7 1956, Amperex 12au7 1953 and 1958~9, and other good choices are Telefunken ECC802s, and 10Mseries 12au7
the best of 5687 are Kuhl TungSol 5687 black plate, Amperex 7119 pinch waist D getter.......and Raytheon brozen plate

 

[rapzoo]

Quote:

Originally Posted by olblueyez /img/forum/go_quote.gif I would like to hear some impressions from some one who has had a chance to listen to the 600 Ohm 880 and 990 on the raptor.

I have not heard the 600 Ohm 990 but I have spent quite a bit of time with the 600 Ohm 880 on my Raptor. Keep in mind that all of my comments are based on listening with a pair of Tung-Sol 5687W blackplates and either the RCA 12AU7 clear top or the RCA 6189. Since both of these RCA tubes are detailed and crisp in their presentation they are probably not the best match for the detailed and crisp 880, but they are what I have had on hand. I have a 1958 Mullard long plate and an Amperex Bugle Boy 12AU7 on order. The warmth of these 12AU7s may mate better with the 880s. Nonetheless, my impressions with the RCA tubes is very positive. The 600 Ohm 880 / Raptor combination exhibits a liquid and natural midrange with clear, sweet, extended highs. Timbre is very good and male and female vocals are both very natural. The soundstage is quite good with good instrument separation and the PRaT is also good. One of the two weaknesses that I have observed with the 880s is eliminated by the Raptor. With many amps, the 600 Ohm 880s exhibit a woolly bass. The bass is there but it is not well defined. I believe that this is the result of underamping. When driven by the Raptor, the bass of the 880s is completely transformed. The woollyness is gone and replaced by a deep, tight and well articulated bass. IMO the second weakness of the 880s is a tendency toward sibilance on some recordings. This tendency is still present with the Raptor, moreso with the clear top than the 6189. I am guessing that the warmer Mullard and Amperex may be able to tame this. I will post my impressions after these tubes arrive.

 

[raffy]

Quote:

Originally Posted by rapzoo /img/forum/go_quote.gif I am guessing that the warmer Mullard and Amperex may be able to tame this. I will post my impressions after these tubes arrive.

I have a 1960s Mullard and from my experience, it tames the sibilance present in certain recordings. It doesn't take it all away, especially and really bad recordings but definitely does help. The sound is overall warmer but detail remains good. YMMV

 

[rapzoo]

Quote:

Originally Posted by raffy /img/forum/go_quote.gif I have a 1960s Mullard and from my experience, it tames the sibilance present in certain recordings. It doesn't take it all away, especially and really bad recordings but definitely does help. The sound is overall warmer but detail remains good. YMMV

Glad to hear your experience with the Mullard, Raffy. It sounds very promising. How was the control on the lower frequencies?

 

[raffy]

Just curious, does anyone here have the old version of the Raptor w/ the old non-plitron power supply? Or did anyone here have the old PS and had it upgraded to the Plitron PS? If so, what were the improvement, if any?

 

[olblueyez]

Ok guys, anyone know what it means when there is a really bright flash below the bottom mica when I turn my amp on? Its the input tube and its only the one tube. The tube works fine, no noise and sounds great. Whats it all about?

 

[wharfrat1]

After another week or so of listening, I still have to say out of my stock of 12AU7's(I have a bugle boy, 1960's telefunken, 1960's mullard, and the stock tube), the Mullard is still my favorite. I have it running with a pair of 60's Raytheon branded Tung-sols. I just love the overall warmth, and the depth it adds to the bass, yet still plenty of detail. It has great seperation on the instruments in a recording, especially live recordings. I have been listening mostly with my HD-650's. Even with a little darker can, this setup has been fantastic.

But, far be it from me to stop tinkering. I just placed a big order today. I should have in the next 7-10 days:
12AU7:
Amperex 7316
1950's Mullard Long Plate
RCA Clear Top
5687:
Matched Pair of the Tung-Sol Ribbed Plate(early 50's)
Matched Pair of the 50's D getter Tung-Sols
Matched Pair of GE 5 Stars

Man, my wife would kill me if she knew what I dropped on tubes today. I'm anxious to here the Tung-Sol ribbed plate 5687's. Supposedly they are the best Tung-Sol 5687's. I am excited to find out.

 

[raffy]

Quote:

Originally Posted by wharfrat1 /img/forum/go_quote.gif After another week or so of listening, I still have to say out of my stock of 12AU7's(I have a bugle boy, 1960's telefunken, 1960's mullard, and the stock tube), the Mullard is still my favorite. I have it running with a pair of 60's Raytheon branded Tung-sols. I just love the overall warmth, and the depth it adds to the bass, yet still plenty of detail. It has great seperation on the instruments in a recording, especially live recordings. I have been listening mostly with my HD-650's. Even with a little darker can, this setup has been fantastic. But, far be it from me to stop tinkering. I just placed a big order today. I should have in the next 7-10 days: 12AU7: Amperex 7316 1950's Mullard Long Plate RCA Clear Top 5687: Matched Pair of the Tung-Sol Ribbed Plate(early 50's) Matched Pair of the 50's D getter Tung-Sols Matched Pair of GE 5 Stars Man, my wife would kill me if she knew what I dropped on tubes today. I'm anxious to here the Tung-Sol ribbed plate 5687's. Supposedly they are the best Tung-Sol 5687's. I am excited to find out.

Where did you find the ribbed Tungsols? I heard those are really rare.

 

[OutdoorXplorer]

The bright flash happens to the Amperex 7316. It's just a short flash and everything else is perfectly OK. Probably it is "Flash by Design"...

Quote:

Originally Posted by olblueyez /img/forum/go_quote.gif Ok guys, anyone know what it means when there is a really bright flash below the bottom mica when I turn my amp on? Its the input tube and its only the one tube. The tube works fine, no noise and sounds great. Whats it all about?

You should be able to get a few off eBay without any hassle..

Quote:

Originally Posted by raffy /img/forum/go_quote.gif Where did you find the ribbed Tungsols? I heard those are really rare.

 

[vcoheda]

yes. amperex tubes flash upon start up.

 

[olblueyez]

Quote:

Originally Posted by vcoheda /img/forum/go_quote.gif yes. amperex tubes flash upon start up.

I take it that refers to some of them and not all of them.

 

[OutdoorXplorer]

Let's run a pooling and see have many of us experience such flashes upon start up....

I would appreciate it as a unique feature of Amperex tubes.

Quote:

Originally Posted by vcoheda /img/forum/go_quote.gif yes. amperex tubes flash upon start up.

Quote:

Originally Posted by olblueyez /img/forum/go_quote.gif I take it that refers to some of them and not all of them.

 

[olblueyez]

Bought 2 and one flashes.

 

[OutdoorXplorer]

I bought 2 and both flashes. Wonder it is by design or defect?

Quote:

Originally Posted by olblueyez /img/forum/go_quote.gif Bought 2 and one flashes.

 

[olblueyez]

Its now 5 in the morning and I have been listening to the flasher all night and this is by far the best tube for the 650. Vocals are perfect and this tube is very 3 dimensional as compared to the others I have tried. Bass is closer to the RCA 12BH7A than the others too. All I have to do is choose 16/44.1, 24/96 or 24/192 on my dac and I get a perfect sound signature for every track I listen to.