“…this tube was actually manufactured in the Mullard factory in India. Still a fantastic tube and delivers that glorious midrange you’d expect from Mullard.”
Continue readingBEL 12au7 Short Plates India
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Rolling with 6as7 tubes
After spending the last few weeks diving deep into the 6AS7 tube family, I’ve finally emerged with a definitive breakdown. While “tube rolling” power tubes comes with the occupational hazard of being hot as hell to the touch—making preamp rolling feel like a breeze by comparison—the sonic rewards are well worth the singed fingertips. Since this family offers a manageable selection compared to the endless sea of 12AX7s, I’ve put together this quick-reference guide to help you find your perfect match.
Continue readingNOS vs NEW – EL34
GE 6829 Long Gray Plates
” Sound was again in the top group for overall detail and tone quality. Low level detail was probably the most apparent of all the tubes tested, and it had a particularly subtle tonal presentation, distinguishing between some hues and colours missed by the others.” Read
“rich, detailed, warm, and thanks to the lower mu, very quiet and low in microphonics.” Read
KT88/6550 New vs Old Stock
Great report on new and old stock tubes – View Report
Bellari HA540 Headphone Amplifier
And now another headphone amp review. I got Bellari because it’s the only headphone amp out there that uses 12ax7 and thus 5751 tubes. So I was excited that I would be able to use my favorite Telefunken, Mazda or Sylvania GB with it. I got the amp really quickly from Amazon ($3 next day shipping with Prime rules!)
This review is going to be very short… I got the amp, yanked out the Shuguang tube – garbage. The first thing I’ve noticed that power supply was puny – 150ma I believe. I was wondering how that little thing could provide enough power to drive filament and the amp at the same time – but it did. I inserted Mazda 12ax7 with Silver Plates – plug my Sennhisers HD650 – lighted a cigar and turned on an album by Diana Panton. The first thing that I’ve noticed, the sound was quite flat and not much airiness to it. I tried both inputs, but with the same results. But what the hell, I had a good cigar. I continued listening for about 30 more minutes and when the cigar was done, I went to try a different tube – I thought that maybe the amp just doesn’t like Mazda. I plugged in Amperex and discovered that only one channel was working. I plugged back Mazda and then Shuguang, but the amp was dead. 🙁
So a very short review – broken amp (awesome return policy with Amazon) – and a sound that didn’t excite senses even with a fantastic tube.
RCA 5692 Red Base
Mullard CV4003/12au7 Box Plates
Bendix JAN 6080
Report on EL84 NOS vs New Production
Another great write up about various tubes in EL84 family for home audio and guitar amps.