canuckaudiog
On a quest for high fidelity
That is the question!
A few of you 104/2 owners out there are no doubt curious about what the KUBE can do for the 104/2. I happen to own one and I've been playing around with it today and thought I'd share my thoughts, now that I've completely restored the 104/2s. I did write up some thoughts on its addition when the 104/2s were unrestored with the original foam donuts caps and fluid and I remember that I felt it made a welcome addition then, but of course now they are back to factory spec and this can change things.
In short, I don't like it in circuit. I couldn't detect much additional bass, considering you're gaining only a little bit of LF extension (goes from about 50Hz flat to 35Hz flat), to me I could hardly tell much difference bass-wise between it on or off. I think you would have to listen to some tracks with deep bass to really benefit, but even then I couldn't tell a whole lot of difference. Maybe it's placement of my speakers, or maybe something isn't quite right with my KUBE, maybe it's the room. Although it works just fine. But seriously, I could not tell a whole lot of difference. With the Extension button engaged yes, I certainly could tell more of a difference.
What I really didn't like about the KUBE though is what it does to the midrange and treble. I found it added some grit to the sound and made it noisier. In other words, more distortion. I know the KUBE does attenuate the sound a bit here, but you could tell it was "dirtying" the sound. It made the midrange less enjoyable and less rich, making it overall tougher to listen to.
However, I have not given up on the KUBE for the 104/2. I still believe a large part of this has to do with the cheaper parts used. One of the folks who designed the KUBEs for Kef posts on another forum and mentioned they really only spent money on the 107 KUBE, which I guess makes sense, but it's unfortunate. My plan is to recap the 104/2 KUBE and replace the op-amps with OPA2604s just like I have done with my 107 KUBE. I have a feeling this will clean up a lot of the issues I'm experiencing.
Basically, I wanted to post this for you guys considering a 104/2 KUBE. My personal opinion is that unless you are willing to hotrod it a bit, stock it's not going to do any good for you. It certainly doesn't for me, and I think one of the sweetest parts about the 104/2 is its great midrange, so this is the last thing you want to detract from.
If you have a 104/2 KUBE and you're curious about doing what I am planning to do, it has 6 TLO72CP op-amps in it. I'm hoping that the OPA2604 will work in place, I can't find a single datasheet on the TLO72CP (lots on the TLO72) so if anyone knows anything I'd appreciate it.
A few of you 104/2 owners out there are no doubt curious about what the KUBE can do for the 104/2. I happen to own one and I've been playing around with it today and thought I'd share my thoughts, now that I've completely restored the 104/2s. I did write up some thoughts on its addition when the 104/2s were unrestored with the original foam donuts caps and fluid and I remember that I felt it made a welcome addition then, but of course now they are back to factory spec and this can change things.
In short, I don't like it in circuit. I couldn't detect much additional bass, considering you're gaining only a little bit of LF extension (goes from about 50Hz flat to 35Hz flat), to me I could hardly tell much difference bass-wise between it on or off. I think you would have to listen to some tracks with deep bass to really benefit, but even then I couldn't tell a whole lot of difference. Maybe it's placement of my speakers, or maybe something isn't quite right with my KUBE, maybe it's the room. Although it works just fine. But seriously, I could not tell a whole lot of difference. With the Extension button engaged yes, I certainly could tell more of a difference.
What I really didn't like about the KUBE though is what it does to the midrange and treble. I found it added some grit to the sound and made it noisier. In other words, more distortion. I know the KUBE does attenuate the sound a bit here, but you could tell it was "dirtying" the sound. It made the midrange less enjoyable and less rich, making it overall tougher to listen to.
However, I have not given up on the KUBE for the 104/2. I still believe a large part of this has to do with the cheaper parts used. One of the folks who designed the KUBEs for Kef posts on another forum and mentioned they really only spent money on the 107 KUBE, which I guess makes sense, but it's unfortunate. My plan is to recap the 104/2 KUBE and replace the op-amps with OPA2604s just like I have done with my 107 KUBE. I have a feeling this will clean up a lot of the issues I'm experiencing.
Basically, I wanted to post this for you guys considering a 104/2 KUBE. My personal opinion is that unless you are willing to hotrod it a bit, stock it's not going to do any good for you. It certainly doesn't for me, and I think one of the sweetest parts about the 104/2 is its great midrange, so this is the last thing you want to detract from.
If you have a 104/2 KUBE and you're curious about doing what I am planning to do, it has 6 TLO72CP op-amps in it. I'm hoping that the OPA2604 will work in place, I can't find a single datasheet on the TLO72CP (lots on the TLO72) so if anyone knows anything I'd appreciate it.