Cap Question

Unknown

I am putting new capacitors (Solen) in my RT-10's and was wondering if there is any benefit to replacing the electrolytic midrange cap (6 mfd) with a poly film cap?
I know the tweeter will benefit, but not so sure about the midrange.
Fresh electrolytic, or poly film on the mid?
Any thoughts?


If it matters: I am also replacing the inductors (Madisound), resistors (Mills), and internal wiring (Nordost flatline).

ben62670

Yes I would replace the 6mf also.

FTGV

According to schem for the RT10 the 6uf is also in the tweeter circuit so yes replacing it with a film cap would be a good move.
IMO there would be no benifit replacing the .3 mh air core coil in the hi pass section.I assume you are replacing the .7mh laminated core inductor with an air core so you'll want to check that the DC resistance of the replacement is reasonably close to the .19 ohms of the stock unit.

Systems

I was planning on leaving the laminated core, as I cannot find one in the same value (.7mH).
The DCR is pretty close in the air core Madisound it being 19awg instead of 22awg for the stock inductor.
I will have to double check that.

Systems

I say it is close, but after checking again, the Madisound air core is .30ohms.

Would it be better to replace the the laminated with air core?
Provided it is close in value (dcr)?

Outfitter03

These two are close:

http://www.madisound.com/store/product_info.php?manufacturers_id=152&products_id=884

http://www.erseaudio.com/Products/XQCoils14Gauge/EAV75-14-680

Both meet the inductance specification but are slightly greater than 10% low on the DCR specification. Solen rounds specifications to two digits less than zero and rates DCR at 0.17 and Erse rates it's inductor DCR at 0.168. 5% would be 0.0095 or a low end specification of 0.1805. 10% would be a lower specification of 0.171.

Someone with more experience than me would need to comment on the effect of the DCR being slightly low in this particular circuit. I would imagine slightly reduced impedance and a little more bass output. Might be a good trade off for the higher quality air core inductor.

F1nut

I would not recommend using Solen caps in the high frequency circuit, far too grainy.

Systems

Thanks for the replies, they are much appreciated.

F1nut wrote: »

I would not recommend using Solen caps in the high frequency circuit, far too grainy.

Any recommendations?

F1nut

Sonicap, Clarity and Obbligato.

FTGV

pepster wrote: »

I say it is close, but after checking again, the Madisound air core is .30ohms.

Would it be better to replace the the laminated with air core?
Provided it is close in value (dcr)?

You may or may not find changing from the laminated to an air core sonically benificial. Depending upon their construction 'some'(not all) cored inductors can be susceptible to saturation at high power levels,the expected result being increased distortion in the bass and midrange.Air cores do not suffer from saturation issues but since they require more copper are more expensive to produce and need to be of a thicker guage to get comparable DCR values.
As I mentioned previously IMO there would be negligable improvement
swapping the coil in the tweeter circuit.

Outfitter03 wrote: »

... more experience than me would need to comment on the effect of the DCR being slightly low in this particular circuit. I would imagine slightly reduced impedance and a little more bass output. Might be a good trade off for the higher quality air core inductor.

The DCR of the coils you linked to are close enough to that of the stock part that IMO should have no net change.Large differential in DCR can cause both changes in level and yes bass response because of changes to the elecrical Q(damping) of the woofer.

Systems

Thanks for all the great responses.

I think I have decided to just change the caps (Sonic Caps), and resistors (Mills) only.
Leave the stock inductors.

The above, combined with the internal wiring swap, and new input cups, should offer a pretty good upgrade for very little money.

The Rt10's are in a bedroom system that sounds pretty good (VERY good cables), B&K Ref 30 pre, B&K 2140 amp, and Rotel 1093 DVD for source.
It's my "Get ready for work" system.:rolleyes:
The system sounds pretty good, but the speakers just need alittle upgrading.

I gave $50 for the speakers, $50 for 8ft. pr. of Nordost Flatlines, and $50 for the upgrade.
For $150 total the speakers should offer good sound, and have good reliability.
Overall the only thing I would get rid of, is the "get ready for work" part!:mad:

Many thanks again for all the great help!

Systems

Wanted to mention I received a pm about this thread, but either I cannot reply because of low post count, or pure ignorance, not sure (prolly latter).

Thanks for the info Outfitter!

F1nut

You have more than 10 posts, so no reason you cannot reply to a PM.