any problem matching these?

beat · « **on:** 25 Oct 2004, 04:35 pm »

Hey all,
I auditioned the purist ..love it. The thing is, I now have new amps and looking to retire/relocate my bottlehead foreplay. I like the flexibility of the purist as well as the sound.. and I don't see why it wouldnt work with these but maybe someone can see something obvious or has some experience..These are my new babies.

http://www.tubeampaudio.com/prod05-MC845-C.htm

maybe I could cover a wider spectrum and just ask if there is some general matching problems to look out for.
thanks, beat

beat · « **Reply #1 on:** 25 Oct 2004, 05:58 pm »

I did a search at the asylum and found this thread. I suppose I need to figure out my amps output impedance which is not listed in the specs...how do I physically measure for that?

http://db.audioasylum.com/cgi/m.mpl?forum=tubes&n=68509&highlight=impedance+matching&r=&session=

thanks again,
beat

tkp · « **Reply #2 on:** 25 Oct 2004, 07:40 pm »

Beat,

You have the other problem, which is SS pre driving tube amp. There are a few parameters of your amp you will need to get.

a) The input impedance of the amp.
b) The gain of the amp or input sensitivity of the amp.

For a), it is almost guaranty to work because SS preamp (the Purist in this case) has very low output impedance (with respect to a typical tube preamp), and tube amp (historically) has high input impedance. This is the ideal condition because it translates into high power transfer ratio.

For b), most if not all today amplifiers design to work with 2V or lower. The Purist has 12 db has gain setting from 0 to 12 db so most likely it will be able to boost the signal from the source to drive the amp to its max power.

Either Curt or I will be able to tell you for sure once you get the input impedance and the gain specs of the amp from the manufacturer.

beat · « **Reply #3 on:** 25 Oct 2004, 08:30 pm »

Thanks Tkp,
I cant find anything on the sensitivity but that shouldnt be a problem with the adjustable gain on the purist, eh? I found the input impedance of the amps are 100k. That give me a ratio of 1000:1 right? the output impedance of the purist is 100 ohms? Is this correct and is it a problem? Seems like a huge ratio.

tkp · « **Reply #4 on:** 25 Oct 2004, 09:11 pm »

You are more than okay. The Purist can drive load as low as 5K ohms so 100K is great.

I don't expect you have any gain issue either because most amp today has gain of 26db or higher.

Red Dragon Audio · « **Reply #5 on:** 25 Oct 2004, 09:22 pm »

Quote from: beat

Thanks Tkp,
I cant find anything on the sensitivity but that shouldnt be a problem with the adjustable gain on the purist, eh? I found the input impedance of the amps are 100k. That give me a ratio of 1000:1 right? the output impedance of the purist is 100 ohms? Is this correct and is it a problem? Seems like a huge ratio.

That is just what you want.

beat · « **Reply #6 on:** 25 Oct 2004, 10:24 pm »

Cool,
done shopping then. Just need to save up a little more.
thanks guys

Curt · « **Reply #7 on:** 26 Oct 2004, 05:31 pm »

Quote from: beat

Hey all,
I auditioned the purist ..love it. The thing is, I now have new amps and looking to retire/relocate my bottlehead foreplay. I like the flexibility of the purist as well as the sound.. and I don't see why it wouldnt work with these but maybe someone can see something obvious or has some experience..These are my new babies.

http://www.tubeampaudio.com/prod05-MC845-C.htm

maybe I could cover a wider spectrum and just ask if there is some general matching problems to look out for.
thanks, beat

No problems with the Purist-Amp impedance match But I don't know what the amps input sensitivity is. As TKP says this should not be a problem either since tube amps are usually >20dB gain and most are >26dB.

I think your all set for your test drive;-) Enjoy.

oris98 · « **Reply #8 on:** 16 Nov 2004, 06:34 am »

I had a ASL AQ1006-845 amp driven by the Purist. The AMP uses 845 and 4x6SN7 tubes. The specs are very close to the one you want to use. The Purist drives the ASL very well. For the $ to sound qty ratio provided by Purist, it is unbeatable ! Very transparent and natural.. I love my purist!