# BHKPre not working with 6DJ8’s? **URL:** \ **Category:** Preamplifiers\ **Created:** [September 26, 2020, 2:09am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203 "2020-09-26T02:09:10Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 26, 2020, 2:09am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/1 "2020-09-26T02:09:10Z")
Hi everyone I’m not sure if this is associated with faulty tubes or me missing something. I recently bought a couple of sets of 6DJ8 tubes for my BHK preamp. I put them in and go no sound. I put the stock tubes back in and they’re fine so it’s not the preamp. I’m thinking maybe I need to move the jumper or are the tubes faulty? I’m not very technically minded so want to ask the question before I start fiddling with things. Thanks ---
**Author:** ![stevem2](https://avatars.discourse-cdn.com/v4/letter/s/cab0a1/32.png) [@stevem2](https://forum.psaudio.com/u/stevem2)\ **Post date:** [September 26, 2020, 2:33am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/2 "2020-09-26T02:33:40Z")
You have to move the jumpers from the 12v to the 6v settings and you may want to move the bias jumpers to the 5 milliamp setting. It’s in the manual. ---
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 26, 2020, 2:34am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/3 "2020-09-26T02:34:36Z")
Thanks. Maybe it’s me but the manual wasn’t clear. ---
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 26, 2020, 2:44am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/4 "2020-09-26T02:44:26Z")
Looks like my jumpers were already set for 5ma… When it’s only on one pin like the attached pic from the manual, I guess this is 4ma and when the two pins are connected it’s 5ma? ![image](https://us1.discourse-cdn.com/flex015/uploads/psaudio/original/3X/e/d/ed2098d0bc765d9aecd21a1fb78b3b7eda8c0871.jpeg) ---
**Author:** ![vee](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vee/32/17567_2.png) [@vee](https://forum.psaudio.com/u/vee)\ **Post date:** [September 26, 2020, 4:57am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/5 "2020-09-26T04:57:47Z")
There are two sets of jumpers. The 6 series needs the 6v and 5ma jumpers set. ---
**Author:** ![kent-tager](https://avatars.discourse-cdn.com/v4/letter/k/eb9ed0/32.png) [@kent-tager](https://forum.psaudio.com/u/kent-tager)\ **Post date:** [September 26, 2020, 12:06pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/6 "2020-09-26T12:06:19Z")
greetings, please read this thread that i started. my experience is that for whatever reason, the 6 volt tubes will not work well and can be problematic. if you are going to use NOS tubes, stick with the 12au7 or a 7DJ8 [Anyone having issues with a noisy channel on the BHK preamp](https://forum.psaudio.com/t/anyone-having-issues-with-a-noisy-channel-on-the-bhk-preamp/19155/61) ---
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 26, 2020, 12:14pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/7 "2020-09-26T12:14:43Z")
Thanks. I spent all day listening to the 6DJ8’s and I don’t like them. They sound harsh. I’ve put my gold lions back in which sound fantastic. I also have some 7dj8’s here I’ll try next. Are they okay to run on 12v? ---
**Author:** ![cocobean1](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/cocobean1/32/38826_2.png) [@cocobean1](https://forum.psaudio.com/u/cocobean1)\ **Post date:** [September 26, 2020, 12:24pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/8 "2020-09-26T12:24:42Z")
JH, the 7dj8 need to be on the 6v setting-12v is only for the 12au7s… good luck. ---
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 26, 2020, 12:29pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/9 "2020-09-26T12:29:38Z")
Thank you… One last question I asked above but didn’t get answered. Is the bias pin at 5ma when the jumper is on both pins? I assume the pic in the manual is the 4ma setting? ![image](https://us1.discourse-cdn.com/flex015/uploads/psaudio/original/3X/e/d/ed2098d0bc765d9aecd21a1fb78b3b7eda8c0871.jpeg) ---
**Author:** ![cocobean1](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/cocobean1/32/38826_2.png) [@cocobean1](https://forum.psaudio.com/u/cocobean1)\ **Post date:** [September 26, 2020, 12:41pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/10 "2020-09-26T12:41:45Z")
this should be helpful. [![](https://us1.discourse-cdn.com/flex015/uploads/psaudio/original/3X/a/0/a023e569793a26bdc7d8db9858a0b137e86ee979.jpeg "Tube rolling a BHK preamp") ](https://www.youtube.com/watch?v=vIKGN8hQazI) ---
**Author:** ![RonP](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/ronp/32/213555_2.png) [@RonP](https://forum.psaudio.com/u/RonP)\ **Post date:** [September 26, 2020, 3:27pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/11 "2020-09-26T15:27:55Z")
To the orig poster, I used Telefunken 6dj8 in my BHK pre. They are my favorite tube in that application and they work perfectly once voltage and current are correct. ---
**Author:** ![tmmuchcox-net](https://avatars.discourse-cdn.com/v4/letter/t/e480ec/32.png) [@tmmuchcox-net](https://forum.psaudio.com/u/tmmuchcox-net)\ **Post date:** [September 26, 2020, 4:56pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/12 "2020-09-26T16:56:28Z")
> [@jhsg](#): > > Is the bias pin at 5ma when the jumper is on both pins? I assume the pic in the [manual](https://www.psaudio.com/support/manuals/) is the 4ma setting? Correct. ---
**Author:** ![watchdog507](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/watchdog507/32/7301_2.png) [@watchdog507](https://forum.psaudio.com/u/watchdog507)\ **Post date:** [September 26, 2020, 5:50pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/13 "2020-09-26T17:50:52Z")
I don’t know where this nonsense about 6DJ8, E88CC’s not working in the BHK PreAmp came from. The amp is designed for them and they work fine. I have used many of these over the years with excellent results. Some can be noisy and those should be disregarded. Not all tubes are equal. Many supposed NOS are actually “Pulls” from old equipment. They may have many hours on them or none. Invest in a Tube Tester and you’re covered. I paid $150 Canadian for my B&K Dyna 606 and it’s like new and has saved my butt many times. My favorites after 3 years with the BHK Preamp are the Telefunken 6DJ8’s. ---
**Author:** ![brett66](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/brett66/32/92201_2.png) [@brett66](https://forum.psaudio.com/u/brett66)\ **Post date:** [September 26, 2020, 6:59pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/14 "2020-09-26T18:59:43Z")
> [@Anyone having issues with a noisy channel on the BHK preamp](https://forum.psaudio.com/t/anyone-having-issues-with-a-noisy-channel-on-the-bhk-preamp/19155/24): > > Eh, it’ll work but I hesitate to recommend using them. We regularly get calls and emails from folks mentioning their BHK pre is popping, hissing, etc. They mention that they have tried multiple tubes so they know it’s not a tube issue. The guys in the lab then test it and sure enough, it fails AP. Check the tubes and 9/10 there will be non 12AU7 inside. That being said, absolutely roll the tubes and have fun with it. Just know that the Pre’s tolerance is only so wide and one could run into nois… Why doesn’t the same occur with NOS 12AU7 tubes (as much as of course there are bad 12v tubes)? The 6v tubes demand more current. ---
**Author:** ![worldwidebeagle](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/worldwidebeagle/32/32413_2.png) [@worldwidebeagle](https://forum.psaudio.com/u/worldwidebeagle)\ **Post date:** [September 27, 2020, 2:08am UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/15 "2020-09-27T02:08:28Z")
Simple, the 12au7 is inherently a much better and tighter spec’ed tube than a 6dj8. That’s why you see it in great $10k pre’s and phono pre’s. Whenever I mention 6dj8s to amp repairmen and amp designers, curse words fly out of their mouths. They are way too hit and miss. And the quality runs the gamut. I am sure that’s what led to having to develop 6922 and 7308s. I have 30 years with that tube and I have seen pre’s that simply will not turn on with them, but they test fine. I spend more time on a Hickok 539b testing, matching 6dj8/7308s than any other tube. Why do you think ARC and Sonic Frontiers used Sovtek 6922 in the 1990s? They sounded MEH but were tightly spec’ed and internally matched. They worked and lasted forever. There are a ton of great nos 12au7s out there, even some new ones are OK. And you can concentrate on sound, not whether if the amp will turn on. ---
**Author:** ![kent-tager](https://avatars.discourse-cdn.com/v4/letter/k/eb9ed0/32.png) [@kent-tager](https://forum.psaudio.com/u/kent-tager)\ **Post date:** [September 27, 2020, 12:21pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/16 "2020-09-27T12:21:12Z")
hey man, it is a surprise to me but when i got a set from Brent Jesse tubes, they were not at all compatible being very noisy and hissy. hard to figure as they should have worked. from his web site 7DJ8 / PCC88: This is an unusual tube that must have had a limited range of specific uses. It is virtually identical to the 6DJ8 except for the heater rating, which is 7 volts Kevin Deal has always recommended the Tungsram 7dj8 as their preferred tube for the preamp ---
**Author:** ![jhsg](https://avatars.discourse-cdn.com/v4/letter/j/54ee81/32.png) [@jhsg](https://forum.psaudio.com/u/jhsg)\ **Post date:** [September 27, 2020, 12:31pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/17 "2020-09-27T12:31:20Z")
Hi mate Once I changed the voltage they were fine and not noisy. I just found them a little more brittle than the gold lions I usually use. However, I like warmer sounding equipment so maybe just not for me. Was worth a try. Thanks. ---
**Author:** ![kent-tager](https://avatars.discourse-cdn.com/v4/letter/k/eb9ed0/32.png) [@kent-tager](https://forum.psaudio.com/u/kent-tager)\ **Post date:** [September 27, 2020, 12:35pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/18 "2020-09-27T12:35:12Z")
these look very promising and are not that expensive. > **[Matsushita / National PCC88 / 7DJ8](https://upscaleaudio.com/products/matsushita-national-pcc88-7dj8?_pos=2&_sid=6abb38afc&_ss=r)** > > Here's a backstory to this tube- > Back in the 80's I had an Audio Research preamp that used 6922's or 6DJ8's. And I was well on my way into collecting tubes and figuring out how they sounded, why, and who really made them. > I went down to an old parts... ---
**Author:** ![markmuse](https://avatars.discourse-cdn.com/v4/letter/m/eada6e/32.png) [@markmuse](https://forum.psaudio.com/u/markmuse)\ **Post date:** [September 28, 2020, 9:19pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/19 "2020-09-28T21:19:50Z")
I have been having a lot of trouble with MATSUSHITA / NATIONAL PCC88 / 7DJ8. They sound great except for the popping and clicking with the volume control. ---
**Author:** ![kent-tager](https://avatars.discourse-cdn.com/v4/letter/k/eb9ed0/32.png) [@kent-tager](https://forum.psaudio.com/u/kent-tager)\ **Post date:** [September 28, 2020, 9:41pm UTC](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203/20 "2020-09-28T21:41:54Z")
thanks. never tried them but they are (or were) possibilities. i have had good luck with the Tungsram 7DJ8 from Upscale but they are no longer available. [Next page](https://forum.psaudio.com/t/bhkpre-not-working-with-6dj8-s/19203.md?page=2)