Forgotten Gem

dalylaleahthor

I forgot that I purchased a Parasound HCA 1000 about 2 years ago for dirt cheap (75 bucks) and recently discovered it sitting in a box in my garage. I forgot the specs so I looked it up and what do you know 400 watts bridged at 8 ohm. Now I had the itch to hook it up to my rti12 (Rtia9 tomorrow) being that people say they open up with the correct power amd what do you know they do. I don't know how to explain it but switching it back and forth between non-bridged and bridged mode. They are louder, vocal more pronounce, bass is tighter and more seperation for the instrument. Now all I need is to sell both my Adcom 545ii and find me another HCA 1000.

skrol

I have a HCA-1000A driving my LSi15's and you are right, it really makes a difference with speakers that are hard to drive.

I was going to pass on the HCA-1000A and look for a HCA-1500 but I think I paid $75 and in need of a little TLC (re-capped, upgraded PS caps, re-soldered some bad connections and biased higher per Mr. Curl's guidance).

I believe the HCA-1000 has four 6,800uF 60V caps in the power supply. This was due to lack of space for bigger caps. On one of the forums, Mr. Curl mentioned that this was an area of compromise. In the 1000A, he was able to use 10,000uF 60V. I was able to find Nippon Chemicon 12,000uF, 80V that fit.

dalylaleahthor

I even try biamping my rtia9 with the Adcom 545 and to my ears that made no difference at all. Maybe it was due to the 100 watt rating but the bridge mode was night and day difference. Maybe one day I'll be able to work up to the Lsim series or even the Paradigm Studio series but as of right now I curremtly own way to many speakers. 13 and counting. Speaker buying is so addicting especially when you find them for so cheap.

PSOVLSK

I think I'm going to rummage around my garage tomorrow and see if I can get so lucky

tonyb

Glad your digging it, but to be honest I think your asking for trouble running it in bridged mode. The 9's dip well below 8 ohms and usually amps in bridged mode don't like less than an 8 ohm load. While it may sound fine for now, I think you'll be overtaxing that amp in the long run.

What this does tell you though, is a beefier amp will make those 9's sing. The HCA 1200 OR 1500 amp should be on your radar. and for the roughly 400 bones they go for should be a no brainer.

dalylaleahthor

Thanks for the reply Tonyb. I understand you with what your saying about the load on the amp but the user manual states 400 watts at 8ohm. I know from experience from car audio that once you start dropping in ohms you start taxing the amp but the ohms stay the same on bridged mode for the amp. Shouldn't it stay the same if the ohm stay the same or am I getting this wrong?

Skrol- Where can I get my amp service? Any good recommendation here in the valley of Califormia?

tonyb

It's not the amp, it's the speakers. That's 8 ohms nominal....which means they can dip below, and they do. The 9's can be a bear to lessor amps, in bridged mode more so.

You have the right idea, sending them more power, but your pushing the limits of the amp and the load the speakers represent to it.....especially at higher volumes. Kinda like running your car with the gas pedal floored all the time, how long do you think it will last like that ?

Just offering some advice my friend, your on the right track, you just need to get an amp that can deal with the impedance swings better that the 9's represent. That is, if you want to keep everything out of the repair shop. I would say enjoy it for now, but keep the volume levels reasonable. However looking for another amp of the same caliber/power isn't a road I'd take. One amp is all you need, you just need a better one is all I'm sayin'.

dalylaleahthor

Thanks for the advice Tonyb. Advices never fall on death ears with me. Guess it's save up time and sell all my amp to fund me a good 2 channel amp or even 2 mono block.

Dennis Gardner

How are you switching the amp from stereo to bridged and still running it to two speakers or did I miss something? I understand how bridging an amp for a single channel can allow doubling of power, but what are you doing for the other channel?

deronb1

This

Inspector 24

Curious, more power is better?
Glad you like the results.

dalylaleahthor

Dennis- I was playing with 1 single rti12. The amp has a mono or stereo switch in the back of the amp. I would play 1 song and during the song I would turn the amp off, switch the banana plug accordingly and turn the switch to mono or stereo. I also forgot to mention that it was going through an Adcom gtp 500ii. No changes was made on the gtp500 meaning volume, bass, treble was kept the same. There was notable difference when the amp powered on from being nonbridged to bridged.

soundfreak1

dalylaleahthor wrote: »

I even try biamping my rtia9 with the Adcom 545 and to my ears that made no difference at all. Maybe it was due to the 100 watt rating but the bridge mode was night and day difference. Maybe one day I'll be able to work up to the Lsim series or even the Paradigm Studio series but as of right now I curremtly own way to many speakers. 13 and counting. Speaker buying is so addicting especially when you find them for so cheap.

Had you biamped using an external xover you would have noticed quite a difference.

dalylaleahthor

Soundfreak- How would I go about doing that? Do I need an external crossover? If so which one?

soundfreak1

A stereo external xover (I curremtly use a rane ac22b) between the preamp and amps
Setting the freq to what your speakers can handle sending only the freq you want to each amp. I send 1k and over to my rta12c's thru my Krell and 1k and below to my JBL L123A'S thru a adcom 555ii.

dalylaleahthor

Thanks for the response guys. Soundfreak- I found a Rane as you had mentioned on Clist. What would be a good price for on as of today?