audio research sp-10

Hello,

I owned the SP-10 for 8 years (1987-1995) and for phono playback, even with the rolled off frequency extremes, a noise floor a bit too high, and mediocre resolution, it was a most incredibly musical component. It took me many years to find something (LS5II/PH2) which had all its strenghths .... and so many of its weaknesses dramatically reduced.

Once I heard the LS5 line stage did I finally realize how poor was the SP-10's line stage. For the first time did I learn that CD playback can be enjoyable.

If you are truly focusing on CD playback, I simply can not recommend the SP-10. But it could very well be a great phono stage that drives (through its tape outputs) a modern line stage.

Concerning the use of the high gain switch position, listen with both and choose the one that works best for you. Newbee is correct that the 12db is an attenuator setting so this surely will cause some loss in the world of "transparency". But there is no "wrong" in using either setting as one position may allow for more fine level adjustment or perhaps the other will allow you to have the volume control around 12 o'clock which is often reported by members here to be preferred for less coloration caused by the volume pot.

Look for the ultra-low noise tubes for the phono section. I used RAM tubes for this and they worked so well. Perhaps RAM Labs still sources such 6DJ8/6922 tubes. Every 6 months or so, as the phono stage became sensitive to noise, I bought another pair or quad, put the new ones in the phono stage and moved the old phono stage tubes to the line stage.

The SP-10 is anything but bright so you can surely eliminate it as a possibility for this trait. If you're system is a wee bit bright, I have found Cardas Golden Cross cables to tone this down and bring on a little more warmth as well.

John

Jafox, FWIW I got so frustrated trying to use RAM sourced tubes in my SP10 I dammed near sold it - noisy, short lived, and not all that transparent. Then they tore down the Berlin wall and we were able to get eastern European tubes at last. I don't think the line stage is all that bad (then or now) if you put some LN, sturdy 6922's in it. I use NOS 6h23s or NOS Sovteks which to some may be coolish, but the gain in clarity is well worth the effort. I pick up a bit of compensating warmth with the drivers in my amps. By the way, I agree that this pre amp is wasted when used only as a line stage. :-)

thanks so much both of you...lol..i am so a newbie..i actually had to look to see what tubes are in the preamp. (my ex bought this whole system for me as a gift) they say ars 6922 E88. would ars mean they are the original tubes ?? i can't move the amp to see what tubes are in there, but i remember the guy my ex bought it from saying something about lots of 6550s and 12ax7s (is that right? geez i'm embarassed.) i haven't used the phono stage yet...wondering now if i might want to switch the tubes from that side to the ls?? newbie..the shanling could be contributing...as it broke in it did get brighter which i thought was quite odd. i do have a marantz 65 se i could try that as an alternative. as for the speaker placement..i'm working on that. the room is 13' by 9.75 and the speakers are now placed 4.5 ft from the back wall and 24 in from the side walls..no toe in...ummm errrr..what are the "first reflection points? nope, haven't listened to neutral systems.. i really have no clue what it "should" sound like. jafox, why is the sp-10 "bad" for cd playing? argh...why don't they tell us this stuff in the rave reviews?? i had the arc ls2 here before the sp-10. nothing bright about it but no "magic" either and very little soundstage as opposed to the sp-10 where i finally heard in person what i had heard audiophiles talk about..every breath..every pluck of the guitar...and i could "see" where all the instruments were...wow what an experience.!! thanks so much for your advice..both of u...i sooo appreciate it!! (and obviously i need it...lol!!!)

The low gain of a line stage is usually for low volume listening or if you have a super high gain power amp. I think some people in old days needed it when taping. The high gain should be the "normal" setting. If you care to retube your SP10 power supply's tube and transistor, I was told by true sound in bay area, it will rivial today's new top preamp even in resolution. A classic preamp.

Where to start :-). 1st, relax about what jafox said - he was addressing the comment to someone with very high level expectations in an advanced system/setup. That SP10 is a far better pre-amp than many new ones sold today and the phono stage is still world class.

You have good ears...if you can tell the difference between the high and low gain stages. My compliments. The low gain stage should be slighly (!) less transparent, you are putting an attenuator in the signal path of the source (Shanling in this case). ARS is the name of the tube retailer, it is not the name of the manufacturer. You will have to gently pull one of the tubes from its socket - you will then find on the tube the manufacturer's name.

Before you start doing a micro exam of tubes etc, I would suggest that you make sure that your speakers are set up to their best advantage - to do that you must have an understanding of their radiation pattern - some speakers are meant to be pointed straight ahead - to listen to them pointed at your listening position will make them sound very aggressive and bright. Such speakers have a wide radiation pattern and will bounce sound off the wall (ceiling & floors) which you refer to as the 1st reflection points - these points must be deadened or the reflected sound will hit your ears mili seconds after the direct sound from the speaker - this will increase the apparent amplitude of the highs and muddy up the direct signal. Since you are dealing with high frequency signals you can usually deaden this area by using heavy wall hangings, book cases, etc - most anything that absorbs sound. As a temporary test, just hang some heavy wool blankets on the walls adjacent to and slightly ahead of your speakers. Also make sure that you have some type of deadening materiel on the floor (carpet/rugs). I have also had a lot of success in small rooms crossing these types of speakers so that the axis' cross well in front of you, at about the same relative angle to your listening position as they are when pointed straight ahead.

Once you have done that, then I would suggest that you become very logical in your approach to solving your problem. I would start with the CDP (which I suspect may really be the problem). Listen to other sources, the better the quality, the better the test. Listen to the Shanling in some ones else system if your can and see how it compares. If you rule out the Shanling as being a problem then you can go to the next step - FWIW, this pre-amp is not euphonic but it is not(!) inherrently bright. Its like an old Ferrari - its still very capable of very high performance if set up and maintained properly but its not one that you would want to just drive about town and to the grocery store.......Hope this helps and feel free to ask more questions, we all want to help.