everything on ebay is ridiculously priced..the AXL chinese amp is priced at rm1.6k while a shop i know sells it for rm900

pasar road dont have ar?

This post has been edited by ryan_hustler: May 27 2009, 02:21 PM

A few shops do have 'some' tubes, NIXIE included but not the popular models.. I saw a Philips tube going for RM58 at NIXIE.

cheap things dont come good. good thing dont come cheap.

Well thanks for stating the obvious. But good things dont have to cost a bomb either.I dont like being ripped off,do you ?

Jazzy: Philips tubes? interesting..hope to uncover some telefunken or army grade tubes

An update on the Nelson Pass F5.

Have been busy looking for F5 parts, especially the resistors and the HEXFET IRF240 series.

Just the resistors will cause a bomb, non inductive and aluminium casing with 15W rating. Man I am not going to blast the speakers full volume. Anyway, the rule on diy is that if u dont get the 'needed' quality, it will be reworks, as always.

The pcb shall be in any time.

Now have problem to find such huge casing and capcitors with 120,000uF. BHC, RIFA Nippon, Dubiler or Nichicon?

This post has been edited by ccschua: May 28 2009, 11:06 PM

ccschua,
Good luck dude!

Heard that LME49810 is not bad too. Any takers. 300Watters measured with SN ratio more than 120dB

I have read the threads on this. Impressive! But I certainly do not need 300W!
My 9Watter( x2) T-Amp is quite sufficient in satisfying my audio needs on top of my other amps (I also have other 'chipamp' to play around like the GainClone).. .. also not to mention the co$t factor. Kinda hard to justify another amp to the missus.. hehe

Keep us posted on your search for the exotic caps.. read your post at diyaudio.com

I had a chance to listen to HEXFET IRFP240 (International Rectifier) and I am really impressed with the smooth flowing and prowess the unit can deliver. Guess that is F5 is getting the attention.

I do not know the sound of IRF240 or IRFP240, the sound of IRF150 and IRFP9150 sound quite nice especially for vocal and chamber music. I use the pair to assembly Pass lab pure class A 10W single ended amp a few year back.

did you match the MOSFET pair on both channel? I have heard people commenting on good sound just off the shelf.

I do not match the pair on both channel. It sound nice once I plug in the power. It do sound smoother after around 48 hour of run in. In term of vocal it do sound close to my EL84 tube set. The original Zen circuit do need a pre-amp to make it more powerful as it only have 1 gain stage and 1 output stage.

What is your power filtering circuit component i.e. the capacitors bank of 120,000uF as well as the transformer. Plitron, Avel ? Is Talema measured up. How do you shield the tranny.

The circuit I build is the Zen. I use 4 pcs of 22000uF capacitor as filter. I do not do any special sheiding on the transformer. I put the transformer around the cornel of the casing then I surround it with the capacitor laying horizontal as sheild. The transformer is just normal EL core make by local manufacturing which locate at Rawang with copper foil around the coil anf the core.

So what choice of cap u use. Does ESR matter to you when u make the selection. Peter daniel has hinted paralleling of say 6x15,000 might be better.

EI for tube amp is commonly used. For solid state, they are seldom applied due to size and the large BW coupling and the EMI?

But I guess beggers cant be chosers. I cant find any toroid with 2x18V above 250VA.

Hey guys,

Is there any amp that can improve the SQ of Sennheiser IE8?

can u show some photo of your built and also whether the amp can give you the micro details and dynamics + soundstage?

OK, but need to wait a little while as the amp is not with me right now, it is at my home town. I am not sure what your mean of micro detail. As per compare, it do come close to SE triode amp as I do heard a lot of detail. To acheive this you need a 10x pre to coupler with it or you need an extra ordinary high sensitive speaker (above 95db). When coupling with the Zen pre or M7 pre, it do give a reasonable soundstage. The amp I build is the original Zen and I used Philip capacitor as filter and Panasonic 105 degree capacitor as output.

Is the 105 deg cap affecting the life or the sound? I plan to use F5 for driving tough nuts like 85dB 4 ohm into 200W dynaudio Focus 110. And for F5 it is easy.

I have just received the board for F5 and here it is. As expected, the board is slightly bigger than a match box.

Hi Chchyong, time to give me your details.

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Added on June 5, 2009, 9:23 amhas anyone seen or use liquid cooling for power amp heat sinks.

This post has been edited by ccschua: Jun 5 2009, 09:23 AM

I've been testing different capacitor brand these few days.. but somehow, i dun feel there is different between this caps..

So i'm wondering whether it is necessary to buy more expensive cap?

cap tested : Ruby ZL, ELNA RE3, PANA FM, cheapo Rudoycon . All in 470uF

wish to have a some discussion with you guys..thanks