aikido headphone amp
May 1, 2007 at 2:23 AM Post #61 of 70
Quote:

Originally Posted by AndrewFischer /img/forum/go_quote.gif
I ordered a pair of Rev. B 9-pin mono boards this week end.


What is different in rev b from rev a? I poked around the site and didn't see anything obvious.
 
May 1, 2007 at 2:55 AM Post #62 of 70
Quote:

Originally Posted by n_maher /img/forum/go_quote.gif
What is different in rev b from rev a? I poked around the site and didn't see anything obvious.


More output tubes. Mostly some dual-triode computer tubes. 5687, 6900, 7044, 7119, 7370, 7892, E182CC. The 9H based tubes are output only. Input is 9A or 9AJ.

More flexible heater jumpers. You can combine 12V and 6V tubes if the 12V tubes can be wired for 6.3V. For example 12AX7 and 6DJ8 can be used. There are also a new few series connections possible but I'm not sure if there are any useful combinations.


For me the most important change, and the reason I got these over the on-sale octal boards is the 5687 support. Some of the other tubes are interesting too. A pair of 6900 tubes are a mere $375 on eBay. I haven't really looked at the rest yet.
 
May 3, 2007 at 11:54 PM Post #64 of 70
I had a listening session yesterday.

I listened to diana krall, metallica, lenny kravitz, mariah carey, fat boy slim, chemical brothers, beethoven 6th symphony.

I must say (not only because I'm bragging) that the sound is much better this time. the harshness that was there when I 1st listened to it seems to be disappearing (or have disappeared). soundstage is still good. and the details are amazing. there were instruments/sounds that I haven't heard before but are present now. bass is still good like the last time. highs are still present.

I cannot guarantee that every aikido would sound the same though as people have used other parts/tubes and power supply used are different.

What I'm sure of is that this aikido seems to be much better than my morgan jones (with cavalli "improvements"). though I used "better" parts on the aikido than my MJ.

more listening tests tonight! I will be putting it my favorite tschaikovsky and vivaldi discs. I was too lazy to get them from the car CD changer last night :|
 
May 8, 2007 at 3:16 AM Post #66 of 70
no photos yet but I have drilled a hole at the back of the chassis to fit a 8cm fan blowing out. the inside can get hot so I decided to use a fan. it's panasonic one and it's very silent.

I have used a 7cm AMD (delta fan) on the heatsink for the DC heater supply as it can get very hot. the delta fan is not quiet at all when the cover is not in place. But it may quiet down to acceptable levels when covered. if not, I'll get an aerocool silent fan.

I had a short listening session last night. Listen's to Tschaikovsky's 1st piano concernto 2nd movement and vivaldi 4 seasons.I like a lot. the "tenderness" to the piano concerto is very involving and the violins in the vivaldi are "sweet as sugar".

the amp is still quiet (no hum).

I'll give it a few more days and I'll probably start painting it on the weekend. I'm hoping for a mirror black finish. I may buy a new can of paint since I have acrylic and it seems enamel is more durable.
 
Jun 19, 2007 at 9:38 AM Post #69 of 70
Quote:

Originally Posted by lordearl /img/forum/go_quote.gif
Jarthel - nice work!

What are the dimensions of your chassis?

Do you have the PSU in a separate chassis?


psu is in the same chassis so the inside is a bit cramp. but the transformer and choke are on top on the chassis.

as for dimensions, i believe it's around 23cm (w) x 35cm (l) x 9cm (h)
==============

I have not finished the chassis. I have sanded it but have not started painting it. the weather here has not been very nice for painting. :|
 
You must log in or register to reply here.

Users who are viewing this thread

Total: 3 (members: 0, guests: 3)
Back
Top