Happy wife........! Good to see you are using the same headphones. I have not spent enough time to replace the stock tube with a 6DJ8 Amperex Bugle Boy yet. Keep us posted on your impressions - two points of view should be interesting.
SparkoS Labs Gemini Headphone Amp
- Thread starter godmax
- Start date
I thought the stock E-H 6DJ8 was decent, the stock E-H 12BH7 not so great. An Amperex BB 6DJ8 will transform this amp to a new level. I also thought the CBS Hytron 12BH7 was a really nice tube as is the highly desirable CBS/Raytheon D-getter 7729, an instrument grade 12AX7 from the 1950s. The Sparkos Gemini is a great little amp and it is easy to hear what different tube variants do to the sound.
Thanks for the tube reccs! I will definitely keep these in mind. Since I know next to nothing about tubes, other than knowing I generally like the sound of them from owning a Schiit Lyr back in the day (and hearing tons of tube equipment at shows and at friend’s places), my plan is to see how I like the stock tube after playing with all the settings and go from there. But if there’s a tube upgrade anyone thinks is a “must” for this amp, let me know!
My only suggestion when buying NOS tubes, especially these dual triodes, is to buy only those tubes that have been tested and whose results are available. The more closely matched (in plate current, Ia) the two sections of the dual triode, the lower the distortion and cleaner the sound. Also, if sections are mismatched enough it will result in a channel imbalance and one section will drift further and further away with use.
ch1525i
100+ Head-Fier
what he said exactly as I now have his "old" awesome Gemini and that 12BH7 is awesome!
Purchased the Amperex BB before the Gemini (had previously purchased tubes for Vali 2++ from a US Ebay supplier) based on recommendations from this forum. Will switch after I have more experience with the stock tube.
Just got my Gemini! First impressions are very positive. I'm primarily comparing it to my Topping A70 Pro, which I also love. But the Gemini's sound is immediately more enjoyable to me. I can confirm that it drives (two) DCA Noire X's (simultaneously) to perfection (for two listeners at once). What an amazing pairing!
If you're a Fiona Apple fan, regardless of what headphone you're using, try "Ladies" off her 2020 album "Fetch the Bolt Cutters." Her voice against the background of sparse drums and bass sounds so rich and lifelike coming out of the Gemini. There's definitely something special about this amp.
Can't wait to crack it open and start playing with the jumpers and rolling tubes, but as of yet I feel no need to do so. It really sounds great stock. I buy a Amperex BB at the recommendation of this forum, so I will eventually, when it arrives.
If you're a Fiona Apple fan, regardless of what headphone you're using, try "Ladies" off her 2020 album "Fetch the Bolt Cutters." Her voice against the background of sparse drums and bass sounds so rich and lifelike coming out of the Gemini. There's definitely something special about this amp.
Can't wait to crack it open and start playing with the jumpers and rolling tubes, but as of yet I feel no need to do so. It really sounds great stock. I buy a Amperex BB at the recommendation of this forum, so I will eventually, when it arrives.
jonathan c
Headphoneus Supremus
I'm glad that you're enjoying Gemini. If you need / would like tube ideas, let me know. PS, note that the power via XLR out is the same as that for SE out.Just got my Gemini! First impressions are very positive. I'm primarily comparing it to my Topping A70 Pro, which I also love. But the Gemini's sound is immediately more enjoyable to me. I can confirm that it drives (two) DCA Noire X's (simultaneously) to perfection (for two listeners at once). What an amazing pairing!
If you're a Fiona Apple fan, regardless of what headphone you're using, try "Ladies" off her 2020 album "Fetch the Bolt Cutters." Her voice against the background of sparse drums and bass sounds so rich and lifelike coming out of the Gemini. There's definitely something special about this amp.
Can't wait to crack it open and start playing with the jumpers and rolling tubes, but as of yet I feel no need to do so. It really sounds great stock. I buy a Amperex BB at the recommendation of this forum, so I will eventually, when it arrives.
I'm all ears! I have an Amperex Bugle Boy 6DJ8 and an Apos Ray Select 12AU7 on the way. Would be curious what others you think I should demo.
Actually, I have a few questions maybe y'all can help me with. I'm a newbie when it comes to tubes, so any help is appreciated.
1. What is a "stage ringed getter?" The Amperex BB was labeled as this. Not sure what it means.
2. If there's a little discoloration/oxidation on the Amperex BB I purchased, is it still alright to insert into the amp? (Pictures below from the listing)
3. How do you know if a tube is reasonably priced? Is there an online retailer that's generally priced right?
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jonathan c
Headphoneus Supremus
1. A 'ring' getter is a halo-shaped construct which holds 'getter material'. This material absorbs / neutralises gaseous impurities so as to keep the vacuum within the tube clean.I'm all ears! I have an Amperex Bugle Boy 6DJ8 and an Apos Ray Select 12AU7 on the way. Would be curious what others you think I should demo.
Actually, I have a few questions maybe y'all can help me with. I'm a newbie when it comes to tubes, so any help is appreciated.
1. What is a "stage ringed getter?" The Amperex BB was labeled as this. Not sure what it means.
2. If there's a little discoloration/oxidation on the Amperex BB I purchased, is it still alright to insert into the amp? (Pictures below from the listing)
3. How do you know if a tube is reasonably priced? Is there an online retailer that's generally priced right?
2. Use Deoxit, or Barkeeper's Friend, to clean the tube pins. Finish off the pins with isopropyl alcohol. Then let warm up in amp.
3. By experience and by asking seasoned Head-Fiers their opinion.
Looking forward to your impressions of the Apos tubes. Just ordered an adapter from Garage to use my GE 5670 tubes from my Schiit Vali 2++ in the Gemini. The adapter changes the 5670 pin outs to the 6922 configuration. Andrew said this should not cause any heater problems with the jumpers in the standard position. I will provide comparisons to the Amp BB which I installed yesterday.
If you are interested in rolling 5670 tubes, there is a good 5670 tube variants thread here on Head-Fi. There are a number of superb 5670 variants like the 2C51, 396A, and 6CC42 for reasonable prices. I bought a pair of Tesla 6CC42s and they brought my amp to a new level.
Thanks. I read that thread when I purchased the Vali and went with the GE JAN 5670 as a tentative first step in tube rolling. It made my HD6xx sound so much better that I decided to move up to the Gemini as the platform for my headphone system. The adapter will provide more options to find the best tubes for me.
jonathan c
Headphoneus Supremus
Here is the adapter that I have used in Woo Audio WA3 and to be used in Gemini.
Thanks for the info! *Purchases Deoxit on Amazon and feels like a big boy audiophile*
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