Another PR99 Question . . . - UK Vintage Radio Repair and Restoration Discussion Forum

Linnovice · 2nd Jun 2022, 3:04 pm

Right, this is getting like Tenko!

I am finally there. The heads are perfect, the motors are perfect and it is now calibrated perfectly according to the manual in CAL mode. On the meters what goes in comes out perfectly on tape. On Quantegy 456 it sounds really great.

My questions is this. As I said, in CAL mode, on the signal generator and meters its perfect but, when I connect to a standard integrated amp (a Technic SU3500) being fed by tuner with full signal on Radio 3 the level that is coming out of the 'record out' into the deck is minimal. Minus 18 to 20dB at most. If I take it off CAL and use the record level controls I get it up to where I would expect it bouncing along just under 0dB with the occasional flash of red on the peak lights. I assume this is normal, but why?

TIMTAPE · 2nd Jun 2022, 3:10 pm

Maybe your are trying to feed the PR99's professional balanced inputs with consumer unbalanced outputs from your amp.

theredhouseinn · 2nd Jun 2022, 4:41 pm

Your PR99 line in is set to 775mv, the o/p from the amp is 150mv, 1 fifth.

Linnovice · 2nd Jun 2022, 5:20 pm

Quote:

Originally Posted by theredhouseinn

Your PR99 line in is set to 775mv, the o/p from the amp is 150mv, 1 fifth.

Why would the output be so low? That does figure though, I've now bought it into my main system with the Linn AV5103 and its fine, a little low but more than acceptable.

I presume then, that anomaly can be addressed by the jumpers on the input board (if necessary)?

Analogue man · 2nd Jun 2022, 11:41 pm

It's not an anomaly 775mv is the professional studio level, it was never meant for domestic use.

Radio Wrangler · 3rd Jun 2022, 12:31 am

775mV RMS into 600 ohms is 1mW and was decided upon as the reference level for telephone signals, and it all expanded form there.

David

Linnovice · 3rd Jun 2022, 1:28 pm

Ok, perhaps anomaly is the wrong word so apologies. But, there are three jumper settings on the input board to allow for connecting to domestic equipment (I presume). It doesn’t explain whether the deck should be setup at 775mV then move the jumper or, move the jumper and then set up at 775mV though.

2nd Jun 2022, 3:04 pm	#1
Linnovice Hexode Join Date: Jun 2014 Location: Chelmsford, Essex, UK Posts: 386	Another PR99 Question . . . Right, this is getting like Tenko! I am finally there. The heads are perfect, the motors are perfect and it is now calibrated perfectly according to the manual in CAL mode. On the meters what goes in comes out perfectly on tape. On Quantegy 456 it sounds really great. My questions is this. As I said, in CAL mode, on the signal generator and meters its perfect but, when I connect to a standard integrated amp (a Technic SU3500) being fed by tuner with full signal on Radio 3 the level that is coming out of the 'record out' into the deck is minimal. Minus 18 to 20dB at most. If I take it off CAL and use the record level controls I get it up to where I would expect it bouncing along just under 0dB with the occasional flash of red on the peak lights. I assume this is normal, but why? __________________ Small Scotch, New Aids and Happy Ears

2nd Jun 2022, 3:10 pm	#2
TIMTAPE Octode Join Date: Jul 2006 Location: Perth, Western Australia Posts: 1,971	Re: Another PR99 Question . . . Maybe your are trying to feed the PR99's professional balanced inputs with consumer unbalanced outputs from your amp.

2nd Jun 2022, 4:41 pm	#3
theredhouseinn Hexode Join Date: Jan 2013 Location: Kelvedon, Essex, UK. Posts: 273	Re: Another PR99 Question . . . Your PR99 line in is set to 775mv, the o/p from the amp is 150mv, 1 fifth.

2nd Jun 2022, 11:41 pm	#5
Analogue man Hexode Join Date: Dec 2020 Location: Raunds, Northamptonshire, UK. Posts: 357	Re: Another PR99 Question . . . It's not an anomaly 775mv is the professional studio level, it was never meant for domestic use. __________________ Graham

3rd Jun 2022, 12:31 am	#6
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,901	Re: Another PR99 Question . . . 775mV RMS into 600 ohms is 1mW and was decided upon as the reference level for telephone signals, and it all expanded form there. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

3rd Jun 2022, 1:28 pm	#7
Linnovice Hexode Join Date: Jun 2014 Location: Chelmsford, Essex, UK Posts: 386	Re: Another PR99 Question . . . Ok, perhaps anomaly is the wrong word so apologies. But, there are three jumper settings on the input board to allow for connecting to domestic equipment (I presume). It doesn’t explain whether the deck should be setup at 775mV then move the jumper or, move the jumper and then set up at 775mV though. __________________ Small Scotch, New Aids and Happy Ears