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回覆 (155): As close as I can get
 
Oh yes, that 6922-sized tube looks just tiny next to the GM100 !  
 
thekong
14-07-14
15:59:38
回覆 (154): As close as I can get
Ah, I see, I see!  
 
Is it just the tube is excessively large that makes the output transformer look tiny or perhaps, that everything else in the picture are all giants but still no where placing near the monster size GM100?  
 
 
Its all relative, right?  
bobui
14-07-14
15:52:42
回覆 (153): As close as I can get
Look like a Russian GM100 or 250TH triode to me. If it is the bigger GM100. It has a max 5kv, 1.6A and Pmax of 1kW. In single ended mode, can easily produced >300W if you have a transformer the size of a mini copper.
bobui
14-07-14
15:44:19
回覆 (153): As close as I can get
Radar is not the agent!  
 
Just found out the amp is NAT Audio Magma, the power tube is GM100, which claimes to have an output of 170W :-O  
 
http://nataudio.com/products/all-products/vacuum-tube-power-amplifiers/item/26-magma.html
thekong
14-07-14
15:43:29
回覆 (152): As close as I can get
 
 
There's a Constellation at the back. Why not ask Radar ?
evp1312
14-07-14
15:03:14
回覆 (151): As close as I can get
 
Any idea what this huge tube is ?  
 
thekong
14-07-14
14:55:53
回覆 (151): 7 - 1
今天我又學到新野, 煮好食蛋牛治, 比率一定要蛋7, 牛1. 這個不及格 la!  
 
7蛋, 1牛, ok!  
 
 
 
bobui
14-07-09
07:38:38
回覆 (150): As close as I can get
Wait a minute! Where is the decanter and proper burgundy glasses? Next time allow me to bring mine.  
 
Playing Boney.M on a Verdier Magnum, kind of a bit offensive. Right?
bobui
14-07-07
18:09:52
回覆 (149): As close as I can get
There you are! So, you are spening it all on the French bottles and leave very little for LP, amp, CAS and basically any decent audio stuffs. How could you?  
 
Actually, I was wrong, you could. You really can but please kindly bring me in!  
 
bobui
14-07-07
17:40:20
回覆 (148): As close as I can get
OK, 1966 is too old ? Here is a newer one he show off .....  
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Yes, a bit on the old side & likely lost its charm. burgundy seldom last that long unless it is an exceptional year. The 1971 magnum should be better
Derek2A3
14-07-07
17:19:09
回覆 (147): As close as I can get
 
... & I wasn't on the guess list .... Let me do the dishes sir ....
Cadiver
14-07-07
16:59:06
回覆 (146): As close as I can get
 
OK, 1966 is too old ? Here is a newer one he show off .....
Cadiver
14-07-07
16:55:23
回覆 (145): As close as I can get
A bottle of 1966 might already be over the hill  
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That's probable! Just bring over to me lor!  
 
bobui
14-07-07
16:36:15
回覆 (144): As close as I can get
Can I at least smell the bottle please ...  
 
Tell me where and when, I go and book a flight.  
 
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A bottle of 1966 might already be over the hill
Derek2A3
14-07-07
16:05:21
回覆 (144): As close as I can get
Can I at least smell the bottle please ...  
 
Tell me where and when, I go and book a flight.  
 
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A bottle of 1966 might already be over the hill
Derek2A3
14-07-07
16:05:20
回覆 (143): As close as I can get
ROMANEE-CONTI vineyard, Burgundy
bobui
14-07-07
14:51:52
回覆 (142): Blanc de Blancs
Tell me where and when, I go and book a flight.  
 
A friend of yours was born on 1966?
bobui
14-07-07
14:33:51
回覆 (141): Blanc de Blancs
 
Oh shee, someone just show me a bottle of this they are opening, I am going to throw up now ... This should cost more than my Hi-fi, my car, my son and everything else .... Can I at least smell the bottle please ...
Cadiver
14-07-07
13:00:50
回覆 (140): Blanc de Blancs
Burgundy with short ribs. Care to join?  
 
The wine opener is made and invented by Campagnolo, the most well known bike component brand in the world from Italy.  
 
Mix of wine, bike stuff and good food! Nothing more I want to ask lor!  
 
Where is Chopin?  
 
 
 
bobui
14-07-04
22:20:49
回覆 (139): Blanc de Blancs
Friday night la! What could be more appropriate than winding up a busy week with bubbles and good food. When it comes to Champagne, we have hidden high hand Andxxx recommendation. Here is a blanc de blancs that worth every penny. Frozen white prawns and Feta cheese. Well match la!  
 
Have a good weekend too!  
bobui
14-07-04
21:05:14
回覆 (138): Western Electric DIY
bobui
14-06-28
12:36:21
回覆 (137): Western Electric DIY
This things sound pretty good even on youtube ....  
 
Cadiver
14-06-28
01:43:53
回覆 (136): Dvorak Cello Concerto
Daniel Muller Schott plays Dvorak Cello Concerto tonight at HK City Hall.  
 
I am going la, of course. Popular tune and one of the best Cello Concerto of all time. Still a very small number of tickets @URBITX.  
 
Go la!  
 
 
 
bobui
14-06-27
15:25:31
回覆 (135): Stock up for a party coming!
fuxked !  
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Hearing is not one of my virtue lor. You see, I could easily mistaken a mono recording from a stereo. How on the bloody earth could my ear drums able to identify the sonic pleasure between a 33k load and a 47k in a delicate phono input? Pretty much zero lor!  
 
Show me some resistors carrying the orange, yellow and/or purple bands. I am very certain that I can separate the 33k from the 47k with one eye shut lor!  
 
bobui
14-06-27
13:32:56
回覆 (135): Stock up for a party coming!
you just don't know you are fuxked ! :-)  
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That's very serious! Better do sth before it's too late
Derek2A3
14-06-27
13:27:49
回覆 (134): Stock up for a party coming!
>I am pretty sure I wouldn't be the one that is truly fuxked. I simple couldn't hear any major difference anyway.<  
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So, maybe it is not that you are not fuxked, but you just don't know you are fuxked ! :-)  
 
 
thekong
14-06-27
12:09:36
回覆 (133): Stock up for a party coming!
either you have a lucky match or your truly fxxked !  
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I am pretty sure I wouldn't be the one that is truly fuxked. I simple couldn't hear any major difference anyway.  
 
There have been a few occasions I mistaken a mono record and thinking, oh, the sound stage is wide and bass is thunder. Very good stereo imaging and sound real nice! Only when I moved my ass over to turn the record to the other side that I saw the big four letters, saying "FFRR". Silly me lor! But then, I thought, OK.....I did enjoy Side A. Would I not be enjoy as much because now I realize I am listening to mono?
bobui
14-06-27
10:54:50
回覆 (132): Stock up for a party coming!
Impedance or not, matching is everything and it is make or break as Master Limage said. If you have more you got more chance of fxxking it up or more chances of getting it right. If you don't have enough, either you have a lucky match or your truly fxxked !  
 
Sorry just my 2 cents of useless input. Just stepping in for on9keung !
daiwok
14-06-26
20:39:52
回覆 (131): Stock up for a party coming!
Glad you suggest box speakers to go. At least I get the chance to sneak in a tall girl of the name Maggie. Would be unbearable should a suggestion come from Limage of what must be dumped.  
 
Not having the slightest interests in knowing what CAS, these three alphabets stand for and how it evolve into the home of many high hands. My deep interests is still with the two most simple, well recognized and faithful alphabets in audio, LP.
bobui
14-06-26
18:02:45
回覆 (130): Stock up for a party coming!
>box speakers<  
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Yes, those definitiely have to go  
 
thekong
14-06-26
16:21:01
回覆 (129): Stock up for a party coming!
dump it.  
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What else has to go? I kind of worship Transformers, valves, tonearm, Long play record, box speakers, mu followers and legs. Should I have them dumped like shit instead. Tell me, tell me!  
 
bobui
14-06-26
16:10:13
回覆 (128): Stock up for a party coming!
should have it dumped like shit instead!  
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Better late than never. But before you do that, pls be sure that those PPs & Cartiers are in the treasure box, not to say letting me know when & where you dump it.
Derek2A3
14-06-26
14:47:06
回覆 (127): Stock up for a party coming!
 
 
"cathode followers don't sound good"  
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Good gracious, you should have told me earlier!  
 
I have kept, in my treasure box, an article advocating the invincible merits of the cathode follower which I worship like doctrine. I should have it dumped like shit instead!  
 
limage
14-06-26
14:40:14
回覆 (126): Stock up for a party coming!
"cathode followers don't sound good".  
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He is not the only one that doesn't prefer cathode followers. Some old schools don't even want to admit SRPP or mu-follower exist.  
 
bobui
14-06-26
13:03:22
回覆 (126): Stock up for a party coming!
there is power transfer and there is signal transfer. for maximum power transfer, the impedances of the source and target should be the same. but for home use of pre to power amp interface , it is a signal transfer. the idea behind the x10 etc. is not to let the target impedance which is really part of the output circuit of the source affec the operation mode of the source circuit.  
of course there is the digital interface as well and i will leave that to mdlover.
drwkng
14-06-26
12:59:18
回覆 (125): Stock up for a party coming!
However, as I understand, some professional audio equipment use input / output transformers, and the industry standard seems to be 600 Ohm. So, does it mean the input / output impedance ratio in this case is 1:1 ?  
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Yes, at least that is where they are trying to head towards. 1:1 is the best in signal transfer, there is no room for argument as this has been proved by math. In the pro field, interconnects can be talking about 10s of meters, so leaving them with no other choice.  
 
Side track a bit about this low impedance output. I once read an interview with Bruce Moore, who was questioned why he rarely used a buffer output stage to lower the impedance. And his answer was : "cathode followers don't sound good". Of course, he can be wrong!
Derek2A3
14-06-26
12:41:03
回覆 (128): Stock up for a party coming!
If no buffer stage or any kind of lower impedance output circuit, the output impedance of some old (pre-70s) valve preamp can be as high as 50k or more. Not 3 or 5k.  
 
I am not too concern with impedance matching even if I were to build a pre or phono amp that need to mate with a power amp having a lower input impedance. Simply because there are many modern valve circuits I can adopt that come with fairly low output impedance. 1 K or even less, not very uncommon.  
 
Take 6H30 or 12B4A for example, Their impedance are in just about 1k. If output is taken from their cathode. You can really achieve fairly low output impedance. Some manufacturers even parallel two to achieve a level of output impedance in par with transistor amp but that doesn't always promise good sound. Surely not the kind of sound I prefer!  
 
bobui
14-06-26
12:34:10
回覆 (129): Stock up for a party coming!
>The 27D is one which features 60 Ω output.<  
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60 Ω is really exceptional for a tube preamp, I think the lowest one I have seen was 90 Ω  
 
I wonder whether any buffering stage was implemented in the design!  
 
thekong
14-06-26
12:29:58
回覆 (128): Stock up for a party coming!
 
 
I do not have sufficient experience on impedance matching between the pre-amp and power amp since I've stuck with the CJ for so many years.  
 
In the phono section, however, I did try various MC cartridges with a large range of resistor loadings and they made so tremendous a difference that you simply cannot ignore. The same is true with MC transformer interface. Sort of make or break!  
 
By the same token, I opine, impedance matching between pre-amp and power amp ought to be one parameter worth serious consideration.  
 
Nevertheless, a tube pre can also be very low in output impedance depending on design. The 27D is one which features 60 Ω output.  
 
limage
14-06-26
12:15:52
回覆 (127): Stock up for a party coming!
>I would say many of the older circuits I have tried with relatively higher output impedance sound more relax and smooth. <  
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That is probably because you always use your DIY, or tube, amps which usually have higher input impedance.  
 
Without a buffer, the output impedance of a typical tube preamp circuit could be as high as 3k to 5k ohm, which would more than likely get you into trouble matching with a SS amp like the Pass with input impedance of only 20K ohm.  
 
 
thekong
14-06-26
12:12:03
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