[ClintonL]

I've got a mod for 12bh7's. Not sure to grab one of them or a electro harmonix 12au7

 

[Tom-s]

Get whatever you find cheap.
5687, 12bh7's and e80cc's are all worth it. 
No experience with the EH12au7's. From the new production tubes my Genalex 12au7's Gold Lions best most of the premium NOS IME.
 
Planning on putting a 120uf film cap for the last PS cap. Now using CLCLC (C1=C2=730uf).
As you can see in the picture (with the tape in the position of the capacitor) it could be moved another centimeter away from the PS and chokes.
So the cap would be mounted horizontally above the PS, between the chokes, front to back.
Would this position induce hum?

 
Edit: Change cap value

 

[Idgit]

I found the 12bh7 to be quite an upgrade. Put a 100uf as the last cap after installing one choke.

 

[ClintonL]

What 12bh7 would you reccomend?

 

[Tom-s]

I'm using "Healthkit" 12bh7's grey plate, taken from some sort of machine. Those were made by RCA and i found them for 3€ each.
So IME the common RCA's sound great compared to 12au7's.

 

[Maxhawk]

When I was experimenting with the 12BH7 I was partial to the Sylvania 12BH7. However in my McIntosh MC240 I prefer the RCA 12BH7.

 

[Tom-s]

A side note with the 12BH7's. I use the long black and grey plate versions (Sylvania and RCA). And with all i prefer them with normal 6080's (Currently using a Mullard CV2984).
With more bass heavy tubes like the Bendix 6080's and 6AS7G's (6H13C) there's too much emphasis on the bass for my preference.

 

[vintinfinity]

Just got my (used, built by a first timer and failed install pulled out to the side) basket case speedball boards installed and working. My pop is an old retired tech and he helped me trouble shoot it (he found a broken LED lead on one of the A and B boards, which we fixed) Then installed everything in the Crack amp.
 
One wire was misplaced to the G instead of the O on the speedball board so I was disappointed it didn't work at first, but I had a beer, cooled off and dove back in and found it myself. Couple touches of the soldering iron and it's working great. 
 
Feels good. I got a hell of a deal on it. Now I just need to get a 6sn7 adapter for the vintage RCA and Sylvania and GE tubes I have of that variety, a 12bh7 or two, and install my ALPS pot and maybe eventually some film cap upgrades, and possibly a choke if it's that big of a deal. Plus get some sanding paper and tung oil for the base. 
 
Finally have my end game set up with the HD650s I'm using with it. 
 
Cheers!

 

[DavidA]

  Just got my (used, built by a first timer and failed install pulled out to the side) basket case speedball boards installed and working. My pop is an old retired tech and he helped me trouble shoot it (he found a broken LED lead on one of the A and B boards, which we fixed) Then installed everything in the Crack amp.
 
One wire was misplaced to the G instead of the O on the speedball board so I was disappointed it didn't work at first, but I had a beer, cooled off and dove back in and found it myself. Couple touches of the soldering iron and it's working great. 
 
Feels good. I got a hell of a deal on it. Now I just need to get a 6sn7 adapter for the vintage RCA and Sylvania and GE tubes I have of that variety, a 12bh7 or two, and install my ALPS pot and maybe eventually some film cap upgrades, and possibly a choke if it's that big of a deal. Plus get some sanding paper and tung oil for the base. 
 
Finally have my end game set up with the HD650s I'm using with it. 
 
Cheers!

How about a picture after finished applied?

 

[vintinfinity]

 
How about a picture after finished applied?

It's going to take me awhile. I'm out of expendable funds at the moment, so when I get to it, I will try to remember to get around to picture taking and posting.

 

[deserat]

Finished speedball upgrade last night. Voltage checks after small board install weren't right and it took me couple of days to figure it out. Turns out the stock 12au7 was bad. I dropped a Gold Lion in and everything checked out fine.  Speedball was well worth it. Am feeding the Crack with the Bifrost Multibit and it sings like an angel.
 
Can't turn the volume past 10 o'clock or it's to loud which concern me as it use to sit at about 11 o'clock...  

Am going to have to have a little shoot out between the Crack + HD600 and the Lyr2 + HE 560 later today but for now ... am just layin' back with a big old grin.

 

[vintinfinity]

Does anyone else prefer the stock Crack circuit to the speedball? I had a nice RCA black plate 12au7 in and the stock crack sounded really good to me. With the speedball the bass is better, deeper, more controlled and the attack is faster for everything else. But I kind of miss the lush reverb I was hearing more fully on vocals before I did the upgrade. We will see how it sounds with a 1957 RCA black plate 12bh7 in the speedball circuit soon though, I guess I will decide what to do at that point depending on how it sounds

edit: I tried an rca clear top 12au7 and although it wasn't my favorite on the stock circuit (the 50s rca black plate was) it seems better than the black plate with the speedball. Weird how that works.

Finished speedball upgrade last night. Voltage checks after small board install weren't right and it took me couple of days to figure it out. Turns out the stock 12au7 was bad. I dropped a Gold Lion in and everything checked out fine.  Speedball was well worth it. Am feeding the Crack with the Bifrost Multibit and it sings like an angel.

Can't turn the volume past 10 o'clock or it's to loud which concern me as it use to sit at about 11 o'clock...  


Am going to have to have a little shoot out between the Crack + HD600 and the Lyr2 + HE 560 later today but for now ... am just layin' back with a big old grin.

I think there is no need to worry about the volume control change after the speedball upgrade. I noticed that with mine as well.

 

[DavidA]

  Finished speedball upgrade last night. Voltage checks after small board install weren't right and it took me couple of days to figure it out. Turns out the stock 12au7 was bad. I dropped a Gold Lion in and everything checked out fine.  Speedball was well worth it. Am feeding the Crack with the Bifrost Multibit and it sings like an angel.
 
Can't turn the volume past 10 o'clock or it's to loud which concern me as it use to sit at about 11 o'clock...  

Am going to have to have a little shoot out between the Crack + HD600 and the Lyr2 + HE 560 later today but for now ... am just layin' back with a big old grin.

Did a comparison between my BH Crack + HD-650 vs Lyr2 + HE-560, both sound really good but it depends on the music to make me prefer one over the other.  Would like to hear what your thoughts are on your shoot out.

 

[deserat]

  Did a comparison between my BH Crack + HD-650 vs Lyr2 + HE-560, both sound really good but it depends on the music to make me prefer one over the other.  Would like to hear what your thoughts are on your shoot out.

 
So I've been listening the playlist i put together to make myself feel good about all the money I spend on headphone equipment for couple of hours and flipping between the various rigs.
 
For anybody that's interesting the config is as such
 
Spotify 320 ogg > USB > BiFrost Multibit 

Then either 

Lyr2 > Platnum graded Telefunken from UpscaleAudio
Botthead Crackspeedball > TungSol 5998 + Gold Lion 12au7

Notes on the Lyr2:
I've long since settled on the HE 560 as my preferred headphone for this Amp.  I spent a bit of time with the HD600 plugged into it tonight because I also wanted to get a sense how the HD600 played in the Lyr2 vs the Crack. My  feeling is that the HD600 really isn't the best match for this amp. I also prefer the HE 560 on the Lyr2 to the HD800 ( which is a vastly superior headphone over all ).  The best way I  can describe this is to summon what is often referred to as the Sennheiser Veil.  That's is of course a feeling, your ears may totally disagree. 

Notes on the Crack:
I bought this thing for two reasons. 1) I've never heard a pure tube amp. 2) I could build it and that sounded fun.  I've had the Crack for about a month but just installed the speedball last night. When I plugged the HD600's into the Crack, sans speedball, I was so happy. I know this from my HDVA600, but the cure for the Sennheiser Veil is an amp designed specifically for high impedance headphones. Also I built the Crack and it's the first time I've soldered in 25 years while everything was is within spec, well... 25 years....
 
Music: Lots of variety but all from a playlist I've put together to make myself feel good about spending so much money. https://open.spotify.com/user/deserat/playlist/5y92kYShyn1ekVZmmU2SL0
 
 
Curve: Lyr2/HE 560  flatest. Lyr2/HD600  2, very flat  Crack/HD600  ( Crack turned the HD600 into a bass monster. Who knew. )

Detail: The Lyr2 HE 560 . Lyr2/HD600, Crack HD600 ( it's pretty close with the HD  600 )
 
Soundstage is more nuanced.  
    Crack/HD600 - Sound is closer to the head but it occupies a more holographic space than the other configurations. One can get a better sense of how the instrument is positioned in relation to the mic.
    Lyr2 / HE560 - Sound stage is widest of the three, but not as deep. By this I mean that all the instruments seem further away, but the distance from you ear doesn't vary as much. Instruments exist a liner continuum from left to right there is very little front to back. 
     Lyr2 / HD600 - This really splits the difference between the two above except that it sounds like somebody put a sheet between the instruments and the mic.
 
 
I guess those are the things one is supposed to talk about, but they don't really tell you the difference between the two rigs. In truth I can't tell you I think one is better than the other, or that one is better than the other for certain genre's of music.  I really enjoyed everything I listened to on them both. There are however some very real differences. I think difference is probably best summed up as organic vs mineral.

The Lyr2/HE 560 combo is very mineral, very crystaline, very sharp and to the point. It retrieves more detail and I can imagine that what I am hearing presented to me is very faithful to how it was transcribed. There is more control in the bass, the highs are tighter,  tremolo in stringed instruments is more apparent. 

The Crack/HD600 combo well is organic, leaves blowing in the breeze..  Let's say that if the other combo presents exactly what was recorded, this combo presents what the artist heard while they recorded it. The presentation really just sounds more like you are in a small but sonically superior venue  listening to somebody make music. By that, I mean you don't hear the saliva on the singers lips as they separate but you do hear the impact the air waves have as her voice travels through it.

Last note. I did plug the 560's in the Crack and there is more detail in the Crack than the HD600 is exposing. But getting the volume up to where I was listening caused distortion ( to be expected ) so they only stayed plugged in for few minutes at low volume. Am looking forward to hooking it up to the HD800.  

EDIT: Spend the day with the Crack and and the HD800's. Also bounced back and forth between the HDVA600 and the Crack w/Speedball. Crack out classes the HD600, there is more exposed through the Amp than the headphones know what to do with. The crack vs the hdva left me feeling the above statements are even more true. I feel like the Crack was on par with the lyr2 detail wise, but not the hdva. The signature was not flat but presented more flat with the HD800 and was much tighter throughout the frequency spectrum than it was the HD600. The organic vs mineral was also more apparent, especially when it came to percussion instruments. Imagine, if you would, a drumstick striking a drum head... a well mic'd drum reveals things you'd never hear across the room... the hdva gives you the experience of the mic... the Crack gives you the experience of being in the room. 

 

[Walderstorn]

 

EDIT: Spend the day with the Crack and and the HD800's. Also bounced back and forth between the HDVA600 and the Crack w/Speedball. Crack out classes the HD600, there is more exposed through the Amp than the headphones know what to do with. The crack vs the hdva left me feeling the above statements are even more true. I feel like the Crack was on par with the lyr2 detail wise, but not the hdva. The signature was not flat but presented more flat with the HD800 and was much tighter throughout the frequency spectrum than it was the HD600. The organic vs mineral was also more apparent, especially when it came to percussion instruments. Imagine, if you would, a drumstick striking a drum head... a well mic'd drum reveals things you'd never hear across the room... the hdva gives you the experience of the mic... the Crack gives you the experience of being in the room. 

 
I kinda felt the same comparing my HD800 with my HD600, i like the HD800 also because it sounds less veiled in my ears and perceived "more" (quantity wise) of good sound that was perceived as better (sound wise).