I have received the BHK250 amp. I hooked it up for the 24 hour burn in. I decided immediately to listen to some music to get a reference frame moving forward. This amp is very impressive out of the box. Pace, rhythm, solid image etc. I am keeping the amp. The pre amp has impressive bass but the mid-range is slightly congested and the pitch definition is not quite correct in the treble region. I listen primarily to classical piano music. It might be the tubes? I will continue to listen and see if the pre-amp sound improves. I am comparing the BHK pre to my Audible Illusions L2 pre. The BHK250 is a real winner.
I’d wait a few weeks or several hundred hours before making any changes. It could be the tubes, it could be your interconnects from the Pre to Amp. It could also be your speaker cables. I generally find that changing components is not the end of the cash leaving my bank account.
I can’t quite tell from your post whether the preamp is new, or just the power amp. If they are both new, I would definitely give it at least 200 hours, probably more, and see what happens. I certainly have experienced components where things like bass and treble balance change over the course of break-in. I own a BHK preamp and in my system the sound quality is even across the range.
The BHK pre is new. The new BHK250 is great out of the box. Thanks.
Here are the notes I took while breaking in the BHK preamp. Unlike you however, I wasn’t comparing it to another preamp. I was previously running the DSD directly into the BHK 250.
First impression, not as good as running DSD directly to the amp. Next morning things sounded a lot better, but seemed to regress later in the day. A little apprehensive about purchase, but was also feeling the same way about my other PSA purchases before they were fully broken in.
Been a rollercoaster ride the whole way. Sounded amazing at around 300 hrs, then became dull with bloated bass between 500 and 580 hrs. Back to sounding amazing after 600 hrs.
Final conclusion after 900 hrs, definite keeper. Every aspect of the sound has improved. Hard to listen to the DSD direct now.
I don’t encounter congested midrange with my BHK Pre/250 setup. Still using the stock tubes? If so, I don’t recommend making any more changes to your system for an absolute minimum of 100 hours of listening time until both the Pre and 250 settle in. But … as I’ve ready written elsewhere, the stock Psvanes were dispensed with as soon as I’d accumulated 100-150 hours. Replaced with NOS Telefunkens, Siemens, new stock Gold Lions from my tube box. All were superior to the grayish, thin midrange of the stock tubes and I’ve had zero doubts about the midrange of the Pre since.
Yes - Still using stock tubes. Thanks.
Do keep your ears open as the BHK 250 gets more time on it. Like many of the users in this forum, I noticed changes with break-in. As I recall (and it has been a while) the amp didn’t change as much as the preamp, but did become more subtle and refined with additional time.
One thing to consider in the future is that the BHK250’s resolution can definitely be further improved by getting those stock rubber feet out of the equation. I found that 3 or 4 Stillpoint SS feet improved definition, ambiance, etc. by a noticeable margin. They are a bit pricy but you get what you pay for. Others have found Iso Acoustics Oreas to be a good upgrade but I didn’t try them when I had a BHK250. I did find the Oreas to more evenly enhance resolution across the frequency spectrum than the Stillpoints SS with my PSA M1200 monos but that may or may not be the case with a different amplifier. The BHK preamp definitely takes a while to come into its full potential in my experience.
Can’t speak to Stillpoints, but can speak to Oreas. Found no difference with my BHK Pre. But, YMMV. Isolation devices are a hit and miss gamble. Be sure to buy from a retailer with a money back guarantee. I did. The Oreas were returned. I still maintain, dollar for dollar, the best possible upgrade for a new BHK Pre owner is top shelf tubes. The best the budget allows.
Similarly, I found no meaningful improvements using Stillpoints with the BHK preamp. The BHK250 amp was a different matter. Odd how attention to vibration control can have such different outcomes with different components. My ModWright LS36.5 preamp takes a fairly big step forward in resolution with Stillpoints, my Dehavilland UltraVerve is only slightly improved, and the BHK preamp isn’t noticeably affected at all.