Infinity IRS Beta Mods Query

[msb64]

I managed to track down a set of IRS Beta speakers earlier this year, and was thinking about upgrading dated (20+ years) crossover components. I was wondering if anyone out there has any good component recommendations? I am looking for good bang for the buck mods, and have heard that Sonic Caps might be worth looking into. Any other ideas or information sources would be greatly appreciated. I have included a picture of one of the mid/high tower crossovers, plenty of space on the board and should be easy to work on. Thanks in advance!

[inertial]

Hi,

I have had in the past IRS Delta, the little brother of the BETA

I was a infinity passionate and have used it for confrontate with my DIY speaker.

Yf you have enough money you could be replace that "iron" core inductors with Solen air-core, sure very expansive

Replace also those big electrolityc caps with cheap MKT like Bennic or others.
Imho the solen are ok because they marriage very well the openess of the EMIT-SEMIT, sort of complementary IMHO.
Resistors in the signal path I like Mills.
Rotative L-pads are another point......they are very useful ...but resistor Lpad are better.

Have fun

Cheers,
Paolo

[sreten]

Hi,

It seems a fairly serious attempt already at crossover quality.
The bipolar electrolytics should be replaced if > 20 years old.
They are all bypassed, replacement seems the best option.

/sreten.

[inertial]

You are right Sreten,
but msb64 wants high-end upgrade, cost-no object ! So why do not put that electrolitycs out of the window and replace with enormous MKT?

Cheers,
Paolo

[sreten]

Originally posted by inertial

but msb64 wants high-end upgrade, cost-no object ! So why do not put
that electrolitycs out of the window and replace with enormous MKT?

Cheers,
Paolo

Hi,

In my experience (and others) with quality speakers changing
bipolar electrolytics to other types can unbalance the speaker
if the electrolytic is in a critical position, if it is not, why bother ?

As they are old the electrolytics should be replaced, the other
capacitors should be fine. If upgrading the network is wanted
the position and purpose of each capacitor should be found,
and then possibly "upgraded" accordingly.

Usually more attention is made to series rather than parallel
capacitors, e.g. take a parallel zobel network, try and work
out how a higher quality capacitor would improve matters .....

/sreten.

[inertial]

Sreten,
If I well remember the LOW Enim has a big cap NP in series.
sure the balance can change, this is the reason to try to improving a sound that IS NOT perfect .
and to be honest, imo electrolitic caps sucks, even if bypassed !
Last , I think msb64 could try and will judge for itself
Please, then report his impression also

Cheers,
Paolo

[sreten]

Originally posted by inertial

Last , I think msb64 could try and will judge for itself
Please, then report his impression also

Cheers,
Paolo

Hi,

Its all JMO and of course msb64 can do whatever he likes.
But e.g. chucking loads of money on big and therefore expensive zobel
capacitors for bass units is a very debatable activity for the sensible.

/sreten.

[msb64]

Thanks for the input everyone. By good bang for the buck I mean maximum return for each dollar invested. Like most things in life you reach a point of diminishing returns, and you end up paying a lot more for just a little more gain. I figure my weakest link right now is probably my cd player, an Arcam CD73T. Although a decent sounding unit for it's price, I would not consider it a high end unit. Other equipment includes a Threshold FET10 preamp, Threshold S/500e to power the bass towers, and a fairly modified Hafler DH200 (as per Pooge article mod from the 80s) with WonderCaps/Bypass caps, metal film resistors, large outboard power supply with torroidal transformers, large PS caps etc. I wouldn't mind upgrading the caps in the Hafler as well, one of the reasons I was asking about Sonic caps or whatever brand might be of benefit and cost effective. I have heard a little bit about special diodes and rectifiers for amplifier applications, but it would be nice to hear from someone who has actually had hands on experience with them. I am currently using Audioquest Midnight speaker wire on all towers, and custom made interconnects based on RG174/U cable. I haven't even opened up the bass servo box yet, but I imagine it has components similar to the speaker crossovers. It looks like winter has set in here, so its a good time for some nice indoor projects.

[inertial]

Msb,
can you please post the crossover schematic of the beta's towers so all will be more clear. Please indicate the NP cap and the MKP and the iron core inductors.

I agree with you, that CD plaier is under the level of your system;
Have you considered to add a serious DAC? I see every day persons who sell his wonderful DACs for a few bucks in the audiogon website

Cheers,
Paolo

[infinia]

Originally posted by msb64
I have heard a little bit about special diodes and rectifiers for amplifier applications, but it would be nice to hear from someone who has actually had hands on experience with them.

Regarding amplifier "upgrades" Don't do it... unless it has been well established by a competent amplifier design engineer. I see allot (most all) of the stuff on various forum web sites regarding rectifier diode (fast diode) substitutions that is plain wrong and can result in sonic degradation in fact.