Mark Fenlon's New CHP-70 (note the "P")

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Hi Guys,
Here's my all new CHP-70 driver. Note the all custom colour and tone matching. It's only available in Japan at this time. Maybe going to Germany soon.

Paper cone unit, centre bonded cap. Paper is made in Japan, forming done in Taiwan. As per my custom, it's 100% custom built.

Revc = 3.6 Ohm
Fo = 66Hz
Sd = 50 Cm/2
Vas = 5.0 Litres
Cms = 1.394N/M
Mmd = 4.0g
Mms = 4.2g
Bl = 2.99 T/M
Qms = 3.114
Qes = 0.701
Qts = 0.572
Levc = 0.043 mH
No = 0.195%
Pwr = 18 W
Pwr Max = 36 W
Cone Dia = 71-mm
 

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Ha! Look at that extension. :) I'm seeing a driver that's flat to 15KHz, gentle roll-off of the extreme top to keep things nice & smooth sounding & a -12dB point at about 25KHz. I love the FR that's engineered into these units -subtle lift to counter step loss, slight dip in the sibilence zone lifting up a touch more to inject some presence, & ~ flat until that final slow descent. I bet the Japanese go ape over these things; it's exactly the sort of thing they like.
 
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Hi Mark; Yeah I'm still here after a nasty bout with the Flu! Still enjoying my Alpair 10/ Alpha 15 "H" baffle combo--hard to beat IMHO! Might be fun to try the "12's" with the Goldwood "18" ----maybe I can even work some dovetails into an OB!
Glad your products are doing well.

Pete
 
I'm currently using this amp at home both with CHR-70 in 6 litre BR and Alpair 7 also in BR. Absolutely delicious!!:D:D. Will be building Alpair 7 Pencils soon.

Tony has done a nice job. I've encouraged Tony (Twin Audio) to join Manufacturers to show his work in more detail.

Arrrrrrgh...... my ageing CD player must be replaced soon:RIP:

Cheers

Mark.
 
Hi Mark,

I'm glad you love my 300B tube amplifier. The amplifier used 3 x 6SN7 as input and driver stages to push 300B in class A single end circuit. The sound tends to be sweet and powerful. You made a right choice for Full Music 300B and French 5U4G rectifier and made sonic performance improved a lot. RCA 6SN7GTB is good enough and no need to replace now. Can replace the matched pair Russia 6H8C. Try Full Music 6SN7. The China made audiophile graded tubes are really good.

6SN7-300B-22.jpg
 
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