Dynaco St-70 series II Bandwidth filter questions ?

Dear All,

I was a Dynaco St-70 series II new onwer one month ago and listen so many previously played CD, I feel the bass not enough compare with my previous power amp. (melody Sp3 bypass version). After that I saw many related st-70ii forum and modified totally 7 nos. of caps (3x100uf 100v, 2x100uf 400v & 2x68uf 450v replaced by “100uf 450v”). The result is good! The speed & reactions, bass are improved but the bass still not enough “deep”. Until I saw your forum discussion the st-70ii added the limiting bandwidth filter to cut-off the 17hz & 23khz sound source. Do you know is it the bass not enough deep reason ? If this is true, can I modified the c22 & R33 values to increase the low frequency? Or jump pass the filter, directly form input jacks to after R33 circuit board ?

Many Thanks!

some one can help me please !

stanleyyu wrote:some one can help me please !

Your problems might be elsewhere. bass below 20hz is unlikley to be
missed in most speakers. What is your speakers ?

Lack of "impressing bass" is sometimes a sign of accurate sound reproduction.

Dear Peterh,
I am using the linn kan I speaker. I find the problem only have some CDs, not for all !
thanks!

The Linn Kan was Linn's version of the BBC ls3/5a. It's bass output drops like a stone below 100 hz. I once had Kans that I used biamped with a 9 foot t-line.
I don't understand your having bass issues with Kans and and a stereo 70 since the Kan has no bass.

I don't feel Linn Kans is "no bass" . If you compare with 8 & 10 inch speaker may be no bass!

I agree that something other than the amp is a bigger culprit here.

I've recently added a pair of Rythmik Subwoofers to my speakers that were bass-shy. They are very versatile, and given that the Kans are, as I recall, staggeringly good at what they do, this may be a very good option to add one or two sub woofers.

By the way, where do you have the Kans located? Linn insists their bookshelf speakers be backed up against the wall so the reflected bass can be capitalized on to reinforce the weak bass produced by the speaker itself.

Hi Tube Nube,

My Kans is on top of the Hi-FI cabinet and the back is in between of the RC wall around 8 inch. Is it enough for reflected the bass ?