Modifications to integrated tube amp: experiences?

Hello Knowledgeable Audiophiles,

I am seriously considering having my Onix SP3 modified.
(I don't know why people sell these amps. I love what it does.)
Does anyone have any experience with the modifiers out there (e.g. Parts Connexion, Hot Rod, or others)?
Who would you send your amp to?
I await your replies and thank you.
I had to send my Primaluna to mitch singerman to check out after a spat of an arcing tube. While he had it i asked him what mods would he suggest. The only thing he suggested was upgrading the caps from Solens to Hovlands. It wasn't much and now i can say the amp is singerman modified :)

It did make it sound smoother.
Just wondering,if you love what it does,why do you want to have it modified?
The SP3 is a very detailed integrated, and I have been told that modification will improve the detail.
Also, if the modification will amplify, if you will, the characteristics I like that is to the good.
It can't hurt to have better components installed in an integrated I may want to keep for the rest of my life.
I have used Parts Connection on Shanling mod... he did a good job. Took a little longer than I expected but the out come is very favorable.
What I'm really looking for here is recommendations and experience with so I can decide who best to do the modifications.
I would recommend Kyle does great work..I can't be happier with my Cary PH-302.Located in Califorina
i actually did some mods to my sp3. the unit out of the box has a very warm and enjoyable sound. i added .1 sonicap platinum bypass caps to the coupling capacitors on the power tubes, and on the pre tubes (12ax7 i believe) i replaced those with .1 sonicap platinums. if i were to send it off i would have also had them replace the rectifier with something better, but doing it myself, it was a difficult part to get to.

i noticed increased air and clarity up top and the unit sounded significantly more detailed.


i will tell you this now, none of the mods i had done will change this amp as much as rolling some tubes through it.
12ax7 to the GE triple mica 5751's made a bigger difference to the sound than the mods i did. also changing the power tubes to the valve art 350b made a definite change for the better. it can all be very system dependent though.

if you search my name on the av123 forums you can find some detailed posts and pictures regarding the mods that i did.

good luck and happy listening :)

Thank you so much for your excellent post!


Please save me some time.
Where did you get your tubes, particularly the GE 5751 & 350B's?

you might want to spend some time surfng the av123 forums, as there is a VERY large wealth of information on not only the mods people have done, but the tubes you will want to try in it.

theres a start :)
Thank you, I've read that, but my question was WHERE did YOU get your GE 5751 triple micas and Valve Art 350Bs PLEASE?
I want to know who I can trust to buy these tubes from.

im sorry i have no idea anymore where i got my tubes from.

you might want to surf google there are a few tube dealers that will warranty their tubes.
The best tube dealer I know is Andy at Vintage Tube Services. He offers a money back guarantee and some of the best selection of NOS tubes available. I have bought GE 5751's from him as well as other 5751 and 12AX7 variants.
Agree with Cloo09. Andy is a stand-up guy.
I beg your pardon "Clio09".