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Pete Riggle Personally Selected Loudspeaker Crossover
Capacitors:
Using
my Altec Voice Of The Theatre A7-500 8 ohm loudspeakers as a test bed, I have experimented with a variety of
new old stock non-pcb commercial oil capacitors to find wonderful sounding crossover capacitors. Having made this determination,
I have laid in a stock of these capacitors to share with other audiophiles seeking musical results from their loudspeakers. I
sell these capacitors as Pete Riggle Personally Selected Loudspeaker Crossover Capacitors. Using new old stock capacitors purchased in quantity, I am able
to avoid the prohibitive prices associated with new stock purchases from capacitor manufacturers or from "high end"
audio capacitor manufacturers. An appropriate observation is that many capacitors marketed as audiophile grade components
do not live up to that standard. For those interested in Voice Of The Theatre projects, or similar projects, it may be of interest to check out my
web page devoted to the Altec A7 Voice Of The Theatre loudspeakers, and relevant to Altec A5 Voice Of The Theatre projects.
Click on the following link:
Capacitors currently in stock include:
Type 1, 12.5 uF, 370 volts AC maximum working voltage, no PCBs: $25 each Type 2, 20 uF, 600 volts AC maximum working voltage, no PCBs: $60 each Type 2, 20 uF, 480 volts AC maximum working voltage, no PCBs: $48 each Type 2, 46 uF, 575 volts AC maximum working voltage, no PCBS: $90 each Type 3, 2 uF, 660 volts AC maximum working voltage, no PCBs: $25 each
To obtain capacitance values different from the 12.5 uF and 20 uF,
consider that units may be combined in series or parallel. Two 20 uF capacitors can be connected series to obtain 10 uF. Two 20
uF capacitors can be connected in parallel to obtain 40 uF. Two 12.5 uF capacitors can be connected in series to obtain 6.25 uF. Three 12.5 uF capacitors can be connected in series to obtain 4.2 uF. Two 12.5
uF capacitors can be connected in parallel to obtain 25 uF. Two 12.5 uF capacitors can be connected in series and combined with 12.5uF in parallel
to obtain 18.75 uF. For a given capacitance,
a higher voltage rating will generally have a slight edge in audio performance over a lower voltage rating, whether this
is because the individual capacitors are rated at a higher voltage, or whether capacitors are connected in series to obtain
a higher voltage rating. So when two capacitors are connected in series to obtain a lower capacitance, there is an audible,
if subtle, improvement from the higher voltage rating.
Crossover capacitors for general applications: Pete Riggle
Selected Loudspeaker Crossover Capacitors are an excellent choice for any crossover project. Contact Pete by email, peteriggle@msn.com for
a consultation. Crossover capacitors
for Hiraga/Altec applications: The Hiraga
network (see my Altec A7 page) designed for Altec A5 Voice Of The Theatre speakers (and also perfect for the A7 models) has
three capacitors. C1 is the only capacitor in the low pass section. C2 is the primary crossover capacitor in the high
pass section. C3 is the notch filter capacitor in the high pass section. My experience with the Hiraga network
for the Altec A7-500-8 speakers is that the Type 2 capacitors sound slightly better for C1 than the Type 1 capacitors,
and the Type 1 capacitors sound slightly better for C2 than the Type 2 capacitors. My greatest satisfaction for C3
has been the Type 3 capacitors. Using these capacitors the A7 Voice Of The Theatre speakers sound quite wonderful. Capacitor values for the 8 ohm Hiraga network: Hirga specified capacitance values for the 8 ohm crossover: C1 = 36 uF, C2 = 19 uF, C3 = 1.7 uF
It is difficult to find capacitors with capacitance values exactly matching the Hiraga values. I have substituted 40 uF for C1, 18.75 uF for C2, and 2 uF for C3. This combination sounds wonderful. Frequency response calculations using the Spice program show little difference in frequency response between the values specified by Hiraga and the values that I have substituted.
Recommended C1 configuration:
Parallel combination of 2 each Type 2, 20 uF, 600 volts AC capacitors gives 40 uF. Four each capacitors for stereo pair @ $60 each, $240 USD
Recommended C2 configuration:
C2, Level 1: Type 1 capacitors, 12.5 uF, 370 volts AC. Two capacitors in series gives 6.25 uF. Combine the two capacitors wired in series and then paralleled with single capacitor gives 18.75 uF. Six each capacitors for a stereo pair @ $25 each, $150 USD
C2, Level 2 (subtle improvement over Level 1): Type 1 capacitors, 12.5 uF, 370 volts AC. Assemble three sets of two capacitors in series. Combine the series sets in parallel to get 18.75 uF at 740 volts AC rating. Twelve each capacitors for a stereo pair @ $25 each, $300 USD
Suggestion: Start with C2 Level 1, go to C2 Level 2 as the budget permits.
Recommended C3 configuration: One Type 3, 2 uF, 660 volts AC per channel. Two required @ $25 each, $50 USD.
Total price of capacitors for a stereo pair: With C2 Level 1: $540 USD; with C2 Level 2: $690 USD
Shipping weight, all capacitors for stereo pair: 9 pounds with C2 Level 1, 11 pounds with C2, Level 2
Capacitor values for the 16 ohm Hiraga network:
Hiraga capacitor values: C1 = 18 uF, C2 = 10 uF, C3 = .82 uF
It is difficult to find capacitor valued exactly matching the Hiraga values. I recommend using 20 uF for C1, 10 uF for C2, and 1 uF for C3. Frequency response calculations using the Spice program show little difference in frequency response between the values specified by Hiraga and the recommended values that I have substituted.
Recommended C1 configuration: Single Type 2, 20 uF, 600 volts AC capacitor per channel. Two required for stereo pair, at $60 each, $120 USD
Recommended C2 configuration:
C2 Level 1: Two Type 2, 20 uF, 480 volts AC capacitor per channel, wired in series to get 10 uF with 960 volts rating. Four required for a stereo pair, at $48 each, $192 USD
C2 Level 2 (subtle improvement over Level 1): Type 1, 12.5 uF, 370 volts AC capacitors, three in series gives 4.2 uF; 2 in series gives 6.25 uF; combine series strings to get 10.45 uF. Ten required for streo pair, at $25 each, $250 USD.
Recommended C3 configuration: Still testing; consult with Pete: peteriggle@msn.com
Total price of all capacitors needed for a stereo pair: $442 USD, plus price of C3 capacitors.
Shipping weight, all capacitors for stereo pair: 9 pounds.
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