# BHK Preamp HT BYPass & Tubes **URL:** \ **Category:** Preamplifiers\ **Created:** [August 6, 2022, 11:17pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995 "2022-08-06T23:17:09Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 6, 2022, 11:17pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/1 "2022-08-06T23:17:09Z")
I’m planning to buy BHK Preamp to be used in both 2-Channel and HT system I need this question answered before I make purcahse When one of the input is set to HT ByPass mode are the Tubes ON and they are shutdown? ---
**Author:** ![paul172](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/paul172/32/308402_2.png) [@paul172](https://forum.psaudio.com/u/paul172)\ **Post date:** [August 7, 2022, 1:57am UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/2 "2022-08-07T01:57:42Z")
Welcome @TheNorthMan. I use my BHK Preamp for ht/and 2 channel. You can assign the HT pass thru to any input on the preamp. The tubes are on anytime the power is on. ---
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 7, 2022, 4:04am UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/3 "2022-08-07T04:04:44Z")
@paul172 thanks for the response. My concern is if I use expensive NOS tubes it would burn the tubes even though I don’t need it in HT by pass mode. I currently use Schiit Freya+ that turn offs the tube when I use passive or diff. buffer stage. That’s really a feature I’m looking for. ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 7, 2022, 6:54am UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/4 "2022-08-07T06:54:09Z")
Small signal tubes can go 10,000 hours. Besides, HT sounds great with a little tube love. ---
**Author:** ![Jbearthma](https://avatars.discourse-cdn.com/v4/letter/j/45deac/32.png) [@Jbearthma](https://forum.psaudio.com/u/Jbearthma)\ **Post date:** [August 7, 2022, 1:31pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/5 "2022-08-07T13:31:14Z")
Just to add-on to the replies above–10,000 hrs is a lot of time. I run my BHK Pre in a dual 2 channel/HT setup. I rolled in some pretty spendy NOS tubes right before the pandemic hit. Between my 2 channel listening and my wife’s chosen method of escapism during that period (watching “K Dramas”), the rig got a lot of use (probably averaged around 8ish hours a day for a year or so). When I checked the tube timer around a year later, I think we had clocked around 2800 hours on the tubes. It’s 2.5 years later, and even after running the rig quite a bit breaking in a couple of new components on several occasions, I think it just barely has over 5500 hrs–the tubes still sound fantastic. I shudder to think what all that time would have cost me if I was running true tube amps (given the much more limited life of power tubes), but I’m running BHK 300s (which use small signal tubes as well), so no problem there either. ---
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 7, 2022, 8:17pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/6 "2022-08-07T20:17:31Z")
That gives me more confidence now. I’m using Sylvania Bad Boys 6SN7 NOS in my current Freya amp for past few years and they were bit spendy to buy them. So that’s where I’m coming from. I plan to roll tubes right away when I get the BHK preamp. ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 7, 2022, 8:50pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/7 "2022-08-07T20:50:25Z")
> [@TheNorthMan](#): > > I plan to roll tubes right away I suggest that you listen to it for a few months before you make a change. Getting a new Pre is a huge change. ---
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 8, 2022, 6:29pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/8 "2022-08-08T18:29:03Z")
Yup this will be huge upgrade from what I have. How much burn-in is needed? Also there are few used in MarketPlace but I’m unable to PM or respond to them. Can someone please point out how to contact the seller in Marketplace? ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 9, 2022, 4:49pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/9 "2022-08-09T16:49:18Z")
I can’t remember if there’s a time period for new users where they can’t PM. @Elk - is there a time limit? ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 9, 2022, 4:50pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/10 "2022-08-09T16:50:49Z")
> [@TheNorthMan](#): > > Yup this will be huge upgrade from what I have. How much burn-in is needed? If it’s new, I’d wait a lot. Maybe as much as 400-600 hours. But, I am conservative when it comes to changes settling in. Others will most definitely have other opinions. You just have to wait for them… 😇 ---
**Author:** ![Elk](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/elk/32/1240_2.png) [@Elk](https://forum.psaudio.com/u/Elk)\ **Post date:** [August 9, 2022, 5:00pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/11 "2022-08-09T17:00:41Z")
I cannot look it up now but as i recall it is related to both a short period of time and some activity. ---
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 9, 2022, 5:43pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/12 "2022-08-09T17:43:01Z")
Looks like it was based on time period or post counts I’m able to PM now. ---
**Author:** ![Elk](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/elk/32/1240_2.png) [@Elk](https://forum.psaudio.com/u/Elk)\ **Post date:** [August 9, 2022, 6:10pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/13 "2022-08-09T18:10:48Z")
Very good! ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 9, 2022, 7:52pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/14 "2022-08-09T19:52:48Z")
You really just need to invoke @elk’s name. Things just fix themselves afterwards. ---
**Author:** ![Photon46](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/photon46/32/142920_2.png) [@Photon46](https://forum.psaudio.com/u/Photon46)\ **Post date:** [August 9, 2022, 7:54pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/15 "2022-08-09T19:54:13Z")
It’s always tempting to jump in and immediately start experimenting with different tubes. But I agree with vkennedy61 that reining in that impulse for a while is worth considering. Especially now that PS Audio is using the new Psvane 12AU7-S tube, which I have found to be a wonderful tube that is just as satisfying as any of the numerous NOS tubes I have used. Every tube has its own unique sound and the particularities of any given system may mean this or that tube is preferable, but you are not being saddled with a substandard tube using the tube the BHK preamp now ships with. ---
**Author:** ![TheNorthMan](https://avatars.discourse-cdn.com/v4/letter/t/c6cbf5/32.png) [@TheNorthMan](https://forum.psaudio.com/u/TheNorthMan)\ **Post date:** [August 9, 2022, 8:08pm UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/16 "2022-08-09T20:08:03Z")
Yes that’s why “Save the best for the last” ---
**Author:** ![vkennedy61](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.psaudio.com/vkennedy61/32/41241_2.png) [@vkennedy61](https://forum.psaudio.com/u/vkennedy61)\ **Post date:** [August 10, 2022, 1:45am UTC](https://forum.psaudio.com/t/bhk-preamp-ht-bypass-tubes/29995/17 "2022-08-10T01:45:48Z")
I think what you’ll find after you get used to the new sound is if there’s something you want to tame or enhance. Perhaps the highs are too bright, or maybe you want a more liquid mid-range. It’s really all about the snowflake system you have. All of our rigs are different and we are all chasing our house sound. Have fun!