Full range speakers, SE triode and T-amps |
>   1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43
 
*** ﹝請按主旨作出回應﹞ ***
主旨寄件者更新日期
回覆 (509): photos hosting issue again...
Photobucket has changed its hosting rules again...  
 
Free accounts are now allowed for 25M of monthly bandwidth for viewing only (not 25M of storage limit)..  
 
So far it has been 280M of bandwidth used in my account, wow, thats quite a lot!  
 
It will be reset to zero at month end though and photos will reappear, until viewing bandwidth gets over 25M again....  
 
Will find a good solution.. thanks for your viewing. : )
CFT
19-09-22
20:19:54
回覆 (508): Iancanada diy toys
oh well..my apologies on the photos quality.  
Its photobucket I have been using.....and you know the problem they are facing..  
 
Photos are blurred if viewing from a PC, but are still somewhat OK on a mobile phone.  
 
Please view from a mobile phone in the meantime, as there will be a solution sometime later.  
CFT
19-07-23
22:19:15
回覆 (507): Iancanada diy toys
Iancanada modules:  
 
Pi3 + FiFoPi (reclocker) + ESS controller + ESS 9038 dac + IV stage + LifePO4 batteries charging controller board.(from web)
CFT
19-05-14
12:48:25
回覆 (506): Iancanada diy toys
Our whatsapp diy group had a large group buy of long anticipated Iancanada 2019 modules (FiFopi, 9028/38 dacs, IV stages, batteries charger board, etc.. )and we have started putting them together....more stories later.  
 
https://www.diyaudio.com/forums/group-buys/207438-ian-asynchronous-i2s-pdif-fifo-kit-buy-318.html#post5727881
CFT
19-05-14
12:35:18
回覆 (505): Happy Chinese New Year
祝大家新年快樂,心想事成,萬事勝意!  
CFT
19-02-05
02:10:42
回覆 (504): early 1950s WE755A
Went to a friend's Ping Pong training place to check out his WE775As, housed in a set of wooden antique radio cabinets as young as him. (Him being a member of the Chinese ping pong players team during the Ping-pong diplomacy in the 60s, some photos were posted two years ago)  
 
Well, what can I say, I can understand why this early 1950s pair should fetch over usd10k.. so coherent, beautiful vocal, its really musical~!  
 
Power amp: Quad 303  
Preamp: FM Acoustic
CFT
19-01-19
23:03:09
回覆 (503): Dynavox 3.5" full range
http://feleppa.com.au/speakermeasmid.html  
 
Tested out the Dynavox LY302F the other day.  
 
Very nice driver! Overall better than TC9 for sure~!  
 
No wonder its ranked the highest in the link above.  
 
No woofer assistance needed.
CFT
19-01-19
22:27:45
回覆 (502): Happy diy in 2019~!
Happy New Year!  
 
January 2019 marks the 10th year anniversary of this thread, amazing itsnt it, its now 10 year old! (Thanks to Tanuski's early encouragement on the committment part.)  
 
And, really, hifi (stereo) diy is a fun hobby.  
 
It combines your hifi understanding and experience, your electronic knowledge, mechanical skills, esthetic/artistic senses, together with your creativity and innovation (or your technology transferring ability) into *making something of your own*, that pleases your eyes, boosts your endorphins, and brings about the aural pleasure, which all leads to and for your music enjoyment!  
 
Hope your new year resolution all set and best DIY wishes to us all in 2019~!
CFT
19-01-01
17:16:00
回覆 (501): PTT205 PP Amp
Congrats, thats an excellent tube, a sleeper and a real gem indeed.. :D  
 
The original builder of the amp using this tube is no longer with us... so sad... :(  
 
I can tell you that he bought a full box of them NOS... but have no idea where they are now... unfortunately. Grab this French tube quick if you happen to bump into any...  
 
As for the circuit, its just a very common PP amp circuit, heavily biased but nothing special..though I dont have the voltages in use to say, the output transformer came from a junk vintage English amp which by accident brings the synergy into the play (PP sounds like SE)..  
 
Happy listening!  
 
CFT
18-11-01
22:33:15
回覆 (500): PTT205 PP Amp
Hello,  
Were do find schematic and tubes for PTT205?  
i use those tubes in SE amp.  
Regards  
phoenixOZ
18-10-30
19:08:24
回覆 (760): Zenith fullrange speakers 1958
Finally..got this pair of Zenith speakers circa 1958 on ebay. (^_^)
CFT
18-08-09
21:06:24
回覆 (759): Holey on ebay waveguide
Quite exciting actually as it is very promising...I mean it works very well! (^_^)  
 
Showing that a small full range can work nicely in place of compression driver on horn/waveguide.  
 
Eventually will use minidsp for the EQ and xover functions to a woofer.
CFT
18-07-23
13:58:25
回覆 (758): Holey on ebay waveguide
Last night we tested briefly the Peerless TC9 and one of my favorites - Coral holey Basket (Sony) speakers on waveguide.  
 
Photo showing the Sony Holey loaded to the ebay waveguide.  
 
Throat size is 2" and the paper cone is 2.5" in diameter. Thats a quick trial...will need to smooth out the rim of the throat to avoid rough freq response at upper highs.  
 
Its open backed and so it sounded like when its mounted on an OB panel in terms of the big sound stage, but a bit more dynamic and having same imaging across the room in the listening area. Need more listening time in a proper set up and will have more comment later. (^_^)
CFT
18-07-23
13:48:34
回覆 (757): Another 1" waveguide
The idea of making a synergy horn is to achieve a sort of single point source with directivity controlled over a large range, say down to below 500Hz... Danelys can go down to below 100Hz IIRC.  
 
That ebay horn posted with 2 inch throat can control directivity to ~700Hz...and it can be done by extending the mouth to a wider width for lowering it.down to ~400Hz or so...  
 
The beauty of it ...is that same thing kind of can be achieved by using a single driver (with no xover at critical freq range say 700hz to 7khz where ears most sensitive), guaranteeing phase coherence... though it cannot go down as low but with a woofer say a 15" to pick up the directive continuity....its certainly good.  
 
Power handling wise...say using Aura Whisper as its a full range unit..designed to handle some 60w max...if its only respobsible for a few.hundred hz up...then loudness is not of a concern....it has 84db efficiency but there will be some gain provided by the waveguide so efficiency could come up a notch...or so....but need to look at the required EQ as well...  
 
Here is what i am talking about... very nice response curves after eq and with controlled directivity.down to ~500Hz.  
 
techtalk.parts-express.com/forum/tech-talk-forum/59712-2-aura-whisper-waveguide-loaded
CFT
18-07-19
22:34:01
回覆 (756): Another 1" waveguide
Someone had a Danley to play with...and also heard of a diy one which is equal or better than Danleys...not expensive to build one if you have the time and woodworking skills.. (^_^)  
 
www.diyaudio.com/forums/multi-way/292379-syns.html
CFT
18-07-19
22:08:57
回覆 (755): Another 1" waveguide
But how low can those 2 inches go? Also have to consider sound pressure.  
 
I am eyeing on the Danley SH50 which has twin 12" and goes down to 40-50 hz. Not sure if welborne is going to acquire a pair
Derek2A3
18-07-19
17:02:40
回覆 (754): Another 1" waveguide
Likewise... (^_^)  
 
Learning too... (^V^)  
 
Thats the highly sort after horn system design these days for the horn guys I understand...it does two things beautifully at the same time...high and mid coming from a small focused source at the horn throat while directivity being controlled nicely.  
 
But hey, keep in mind that the 2" full range loaded with the ebay horn posted is supposed be doing the same thing, so worth the try ! (^V^)
CFT
18-07-19
16:49:17
回覆 (753): Another 1" waveguide
I am not a horn guy, but do love to witness what this synergy horn could do.
Derek2A3
18-07-19
16:06:59
回覆 (752): Another 1" waveguide
They all say this 1" waveguide is good.  
 
B-52 PHRN-1014 1" Horn 10" x 14" Bolt-On  
 
Its a copy of the PRV one (that I missed out) which in turn a clone of a Qsc.  
 
And I finally pressed the buy button on the Parts Express site last night, along with the purchase of a pair of Aura whisper plus two techtronic Element 2" units (for the 2" ebay waveguide), all buyout items at a discount.  
 
CFT
18-07-18
18:27:46
回覆 (751): audio-gd C39 preamp and modules
yes, some collection of amp design topologies!  
 
Missing diamond amp, single ended, etc..  
 
Most recently filled that up with AD844 OTA, satri, Dartzeel and Marantz amps with diamond non feedback structures..and ASKA pre and ALPHA single ended amp..etc...
CFT
18-07-18
18:16:29
回覆 (750): audio-gd C39 preamp and modules
CFT HING GOOD JOB  
 
I LIKE ML-2 THE MOST.
ghost
18-07-18
08:16:02
回覆 (749): audio-gd C39 preamp and modules
CFT
18-07-17
21:56:30
回覆 (748): audio-gd C39 preamp and modules
CFT
18-07-17
21:55:19
回覆 (747): audio-gd C39 preamp and modules
CFT
18-07-17
21:54:24
回覆 (746): audio-gd C39 preamp and modules
After I bought this audio-gd C39 preamp and the interchangeable modules back in 2006.. I was telling myself that there would be no need for doing ss diy preamp any more..as one can swap in Marantz, Accuphase, Mark Levinson, Musical Fidelity modules...all in one chasis powered by shunt regulators. (^_^)  
 
From Audio-gd web archive:  
 
C39 preamp:  
www.audio-gd.com/PRO/pre/C39/C39MK3EN_Custom.htm  
 
Modules:  
www.audio-gd.com/pro/diy/MD/MDEN.htm
CFT
18-07-17
21:44:09
回覆 (745): Linkwitz speaker systems
It was yesterday ....I came up with a transformation plan for my Pluto/LXmini.  
(^V^)  
 
Lately I have been looking into ways of making synergy horns..and it looks like using a single tiny 2" full range unit on a horn as mentioned in post #740 sounds promising based on some others reports, and by such a way perhaps there is really no need to do a synergy horn with multiple drivers yet can still achieve extended controlled directivity..but what about taking one more step and synergize it with a woofer instead, crossing at ~500 Hz to cover down to ~40 Hz or so...and in this case it needs an enclosure. Then the Pluto mid woofer solution all in a sudden came out of my mind. (^V^) YES, just land the horn over to that mid woofer and cross at the LXmini xover freq ~700Hz!  
 
So there are three changeable heads now I could be playing with the mid woofer portion of the LXmini.  
 
1) the omni (< ~4khz) Pluto head with the Aura Whisper 2" driver. (later can try out the Aura Cougar 1" diameter with 3/4" cone for achieving omni ~<10khz)  
 
2) Seas full range (OB) as in LXmini.  
(or using some vintage full range units as a general FAST system)  
 
3) Synergy horn with a 2" fullrange at apex and two small side holes for the mid woofer sound to filter through. (so all sound coming out thru the horn).  
 
Itsnt it fun! (^_^)  
CFT
18-07-15
22:22:55
回覆 (744): Linkwitz speaker systems
Then came 2006 in HK...after hybernating for over a decade of no hifi diy, one day on web I discovered that Linkwitz had a website and his latest system was called Orion and there was also the little brother, Pluto that was just launched in 2005! It was love at the first sight and so I decided to build a set.  
 
A lot of work and time was put into it but really worthy. Its still playing in the living room today since 2007. This is my second set of Linkwitz system.  
 
And in 2014 the LXmini was introduced... so I got all the necessary parts for upgrading my Pluto to it.
CFT
18-07-15
21:44:50
回覆 (743): Linkwitz speaker systems
Built my first Linkwitz system in happy school days, using KEF B110s and modified Audax tweeters, but was mixed in with the TL-10, a 6 foot tall transmission line subwoofer by Gary Galo as the center subwoofer channel.  
 
And here it is the series of articles:  
 
A Three-Enclosure Loudspeaker System with Active Delay and Crossover.  
 
Item #12  
www.linkwitzlab.com/publications.htm  
 
Learned so much from those Speaker Builders (and The Audio Amateurs) magazines where I got the Linkwitz aricles from - at the headquarters of the Audio Engineering Society in NYC. (My luck that the president then allowed me to make photo copies as much as I wanted from the library...as a kid that was an easy luck I suppose...but still could recall his secretary Eileen was a bit in awe as I literally spent hours by the photocopier for a few rounds.
CFT
18-07-15
20:12:21
回覆 (742): NDK duculon testing
Albert just put together a PCB for the duculon trial...exciting! (^V^)  
 
1pekingroad.com/zaspx/topics.aspx?topicsno=4&subjectno=83176&uppersubjectno=83176
CFT
18-07-12
19:16:28
回覆 (741): horn loaded tiny fullrange speakers to ~400Hz
This horn could hold the constant directivity to 700Hz or so but could load down further...good enough* (^_^).  
(could further lower the constant directivity by extending the mouth area...)  
 
* According to Dr. Griesinger's research which demonstrated that 700-7000Hz is the critical range of frequencies where our hearing and our brain combine the fundamental sound with its harmonics.  
CFT
18-07-05
15:39:07
回覆 (740): horn loaded tiny fullrange speakers to ~400Hz
Bought a pair of horn waveguides (17"W x11"H) with a two inch throat for loading with small full range drivers (nope, not compression drivers) - like HiVi A2S, Aura whisper/Cougar, SB Acoustic 2.5" etc.  
 
Some are loading them down to 400 Hz with great results. (^_^)  
 
Synergy horn type of mod can be done on them too..good deal. (^V^)
CFT
18-07-04
22:02:25
回覆 (739): MJ Audio Festival - March 2018
多謝 CFT 兄的美言 , 窮就是動力  
 
 
1 pekingroad 有好多猛人, 我只是個飲奶中嘅學神.
ghost
18-06-17
18:13:52
回覆 (738): MJ Audio Festival - March 2018
期待!  
ghost 兄的前及後級皆超diy傑作! (^V^)
CFT
18-06-16
09:32:52
回覆 (737): MJ Audio Festival - March 2018
最近有空開始預備改良我部老爺大功率後級  
__________________________________________  
 
 
等睇嘢!
Derek2A3
18-06-15
09:56:34
回覆 (736): MJ Audio Festival - March 2018
更正應該係 R2R 32_BIT PCM DSD 硬解 DAC
ghost
18-06-15
09:19:35
回覆 (735): MJ Audio Festival - March 2018
改良中
ghost
18-06-15
07:57:29
回覆 (734): MJ Audio Festival - March 2018
我部係 R2R 24_BIT PCM DSD 硬解 DAC, CD,WAV,FLAC,DSD files 可直接硬解輸出到前級.  
 
最近有空開始預備改良我部老爺大功率後級.
ghost
18-06-15
07:56:03
回覆 (733): MJ Audio Festival - March 2018
正!  
 
R2R type 以前得Total dac 之類貴廠機。。而家diy 都得。 (^_^)  
 
最近留意一部signalyst - dsd to analog filter...see post #707 幾過引。。  
 
upsample pcm 去 dsd 256/512先, 跟住去這filter, 板沒有自己的clock, 只是作filtering用...應該會很好声。(^V^)
CFT
18-06-14
16:06:47
回覆 (732): MJ Audio Festival - March 2018
R2R 32 BIT DAC FOR MY CAS SYSTEM
ghost
18-06-14
14:18:56
回覆 (731): MJ Audio Festival - March 2018
我諗遲多10年香港僅存的電子零件鋪都無埋  
__________________________________  
 
 
對,反正價錢平,壞就成件換新,整都無謂。 DIY 嘛,直頭戇居啦!  
 
___________________________________________________________  
 
DIY 直頭戇居 哈哈  
 
我揸慣辣雞 有時都好難收手 前年手痕又整部 R2R DAC 辣雞佬睇見支辣雞就會技癢
https://c1.staticflickr.com/5/4282/35665113121_f286909018_h.jpg
ghost
18-06-14
14:13:05