System Problem

[ssarm@mac.com]

I just bought a Technics TT yesterday. Still in the original box, still in the originally packaging. Never used.

I just connected it to the phono input on my preamp, and when I tried to play a record, no sound was getting through to the speakers. I usually play my music through my computer, so I know its not a problem with the power amp.

Can anyone give me any clue to what might be wrong/how I can fix it?

Thanks.

[jrhymeammo]

Dear Ssarm,

Your posts will always be welcomed in Analoge section.

First make sure you have it connected to phono-in again with groundwire grounded.
What type of cartridge do you have? As long as you have high-output Moving Magnet (MM) cartridge you should be fine. You may also use high-output MC cartridge.
I've never heard of Technic SL-5200. But I'm wondering if it has phono pre build in. If it does you should be able to hear more than anybody you like.

Check your Cartridge wiring on your tonearm/headshell.
How about posting pictures of your tonearm/cart and your TT?

-JRA

[ssarm@mac.com]

I don't have a digital camara with me. The cartridge is a M95HE.

I don't think its a problem with the turntable. I had one at home, and I had the same problem when I tried to play a record: the TT would seem to be running fine, but no signal would be getting to the speakers.

Is there anyway I can inspect my pre-amp to see if something is wrong? I tried to call adcom, but they aren't open on weekends.

Thanks

[jrhymeammo]

Here is one way I know how to check.
Just plug it into your other input, like CD or AUX. turn it up as much as you can. you should be able to hear "slight" sound. If you can, then it's not your TT. Also, I believe your Adcom phono stage has maximum of 43db gain.

-JRA

[markw]

Here is one way I know how to check.
Just plug it into your other input, like CD or AUX. turn it up as much as you can. you should be able to hear "slight" sound. If you can, then it's not your TT.

-JRA

If it turns oit it it the Adcom, there's really not much you can do to fix it yourself. IT's not like replacing a tube or the like.

Good luck.

[jrhymeammo]

If it turns oit it it the Adcom, there's really not much you can do to fix it yourself. IT's not like replacing a tube or the like.

Good luck.

Thanks you MarkW.
Like you said, there is nothing we can do to help fix his Adcom(if it's broken). Playing his TT thru CD input will determine if his Technic has faulty wiring.
You cartirdge output should be just strong enough for you to faintly hear music thru your speakers.

[ssarm@mac.com]

I didn't hear any sound coming out of the other inputs (CD, Tuner). I plugged into my signal processor in, which i use for my computer line, and its working.

Can I get a connector that will let me run both the computer line and the phono line into the signal processor in, so I don't have to constantly change them?

Thanks.


EDIT: the sound sounds overly bright, I can't hear any bass even with the equalizer knob maxed out. I would think this is happening cause the TT isn't plugged into the phono input?

[markw]

EDIT: the sound sounds overly bright, I can't hear any bass even with the equalizer knob maxed out. I would think this is happening cause the TT isn't plugged into the phono input?

You are correct. What you are hearing is what a magnetic cartridge sounds like when played through a line level (non phono preamp) input.

You've isolated the problem. The Turntable/cartridge is working fine. The phono preamp in the Adcom is not.

[Mr Peabody]

He tried it through the phono input and another input and it didn't work but he tried it through the processor bypass and it worked, keep in mind the processor bypass goes directly to the power amp and would have much more gain that way than any of his other inputs. I'm not familiar with that preamp but just because an input says "phono" doesn't necessarily mean it has a phono stage built in. I'd try playing your computer or CD player through the phono input to see what happens. Either way you know the TT works and it would probably be cheaper and better sound to buy an outboard phono stage than have your preamp fixed.

[markw]

I'm not familiar with that preamp but just because an input says "phono" doesn't necessarily mean it has a phono stage built in.

I would be very surprised by this and, IMNSHO, would think this was misleading and verges on false advertising.

Either way you know the TT works and it would probably be cheaper and better sound to buy an outboard phono stage than have your preamp fixed.

This also is an option. They start at about $25 and go up from there, but better sound" could wind up costing a pretty penny.

Edit: It does have a built in phono stage:

SPECIFICATIONS:

Total harmonic distortion: 0.005%
IM distortion: 0.005%
Signal to noise ratio:

Phone (re 0 .5 ): > 85 dB
Tuner, CD, Tape (re 2 V output): > 100dB
Tone Controls:

Bass (40 Hz) 9.5dB
Treble (15 kHz) 9.5 dB
Contour (switchable): + 6dB at 50 Hz
Frequency response: 1 Hz - 100 kHz o.1 dB
High filter (switchable): -2.5 dB at 20kHz (6dB/octave)
Low filter (switchable): - 6dB at 20 Hz (6dB/octave)
Input sensitivity for 0.5V output


Phono High MC/MM: 0.4 mV
Phono Low MC: 0.13 mV
High: 40 mV
Maximum output level: 10 volts
Input impedance:
High MC/MM: 47 kohms
Low MC: 100 ohms
Output impedance: 470 ohms
Phono overload at 1 kHz High MC/MM: 140mV
Phono input capacitance: Adjustable; 100 pF, 175 pF, 275 pF

Line voltage: 120V/60 Hz (Available in 230V/50 Hz on special order)
Dimensions: 17" x 3 1/4" x 12 3/4" D(432 mm x 83 mm x 324 mm D)
Weight: 14 lbs (6.4 kg)


Hint: You might want to explore this "high/Low" thing before giving up hope. Play around, check the manual, explore the rear panel, whatever...

[jrhymeammo]

http://www.adcom.com/data/manuals/gfp555manual.pdf

Dear Ssarm,

I'm gonna go thru this like you are 5 year old. I like to do this to make sure we have all the information. It is not my intension to treat you like one. So let's go thru this for your sake.

Go to page 4 on this manual.

First thing as manual states.
"Turn power off before changing phono setting"
okay, everything is off.

-You have TT's wire grounded to 1, right?
-Do you have TT's RCAs pluged into 2?
-Since you have HIgh output MM cart, be sure it is set to that on 2.

Your Listening knob next to your volume knob is aimed at 12 'O clock.

Also, I really dont think it'll do anything but unplug anything that is connect to Tape-OUT.

Turn on your preamp and see what happens.

-JRA

[ssarm@mac.com]

You guys have been a great help, but unfortunately I think the phono is dead on my preamp.

http://www.needledoctor.com/Online-S...ERPRICE&range=

Should I pick up the Btech (50) or the Bellari (76), run my TT through that, and run the output of the phono-preamp into my "signal processor in" on my adcom preamp?

[jrhymeammo]

You guys have been a great help, but unfortunately I think the phono is dead on my preamp.

http://www.needledoctor.com/Online-S...ERPRICE&range=

Should I pick up the Btech (50) or the Bellari (76), run my TT through that, and run the output of the phono-preamp into my "signal processor in" on my adcom preamp?

I'm glad you posted before making your Purchase.

Bellari VP29 is the worst audio product ever made in last 100 years. Please take my word seriously.
THE WORST!!!!!!
That product was rarely available before Bellari VP129 hit the scene.
Shame on Jerry Raskin for even selling that product!!!!!!!!!!!!!!

Also, I dont have experience with other onw you mentioned. Based on specs, I would advise you to stay away from it.

http://buy0.audiogon.com/cgia/fsb.pl?preaphon&1&ctg&st1

If you are on sub $80 budget then you should keep your eye on Audiogon. This is too late, but will give you some ideas. http://cls.audiogon.com/cgi-bin/cls....hon&1163904643

[jrhymeammo]

Just you give you a better idea of Bellari VP29

I briefly use it with Paradigm Monitor 5s, Rotel receiver, and Pioneer PL-1000w/ Grado Green.
It will sound like you punched holes in your drivers and played your speakers facing down on your carpet.

I am not exaggerating.

-JRA

[Mr Peabody]

If you use an outboard phono stage don't run it through your processor in, use one of your other inputs. You can't control the volume when using that processor input can you?

I'm not sure what they are used but the Creek OBH-8 is a good little phono stage. They are about $180.00 new.

[ssarm@mac.com]

Thanks again.

I run my computer line through the processor in, and I am able to control the volume on both my computer and the pre-amp. My original thought process was that I could just get 2 2-1 splitters, and run both the computer line and output line from the phono-preamp into my adcom preamp.

What are some specs I should look for in a good phono preamp? I would like to buy used/new for around $100. I know it won't be superior quality, but I'm kind of strapped for cash right now.

And just so I know, about how much would it cost to get the adcom unit fixed up? I plan on calling adcom tomorrow, but if you guys have a rough idea, it be helpful.

Thanks a lot.

[markw]

I run my computer line through the processor in, and I am able to control the volume on both my computer and the pre-amp. My original thought process was that I could just get 2 2-1 splitters, and run both the computer line and output line from the phono-preamp into my adcom preamp.

Forget the signal processor and splitter idea. Trust me on this. Simply use a regiular line in on the preamp.

What are some specs I should look for in a good phono preamp? I would like to buy used/new for around $100. I know it won't be superior quality, but I'm kind of strapped for cash right now.

For that price you won't get too much choice. NAD is supposed to put out a decent one for a little over $100 or so.

And just so I know, about how much would it cost to get the adcom unit fixed up? I plan on calling adcom tomorrow, but if you guys have a rough idea, it be helpful.

For this, you would need to contact a technician. You might google for tech who do this and ask them. Some charge a flat rate plus parts. Radio Shack does and they might be worth a visit to find out.

[Mr Peabody]

If your strapped it may be worth getting a quote for a fix. Your processor loop must not be what I thought it was. Most processor loops will link the front 2 channels of a surround source directly to the power amp and by everything else in the preamp including volume control.

[markw]

If your strapped it may be worth getting a quote for a fix. Your processor loop must not be what I thought it was. Most processor loops will link the front 2 channels of a surround source directly to the power amp and by everything else in the preamp including volume control.

In my experience, "External Processor Loops" are essentially the same as tape monitor loops in that they take a line level signal, of a constant level, right after source selection, send it out to an equalizer or some such, and return it into the signal path just before the volume control.

Of course, tape monitors can generally be controlled by a switch like a tape monitor. in my MAD 1600 ther's a switch labelled "EPL" ...not here though. You need interconnects.

[Mr Peabody]

You are right but when he said "external processor" my brain was thinking "processor bypass". This is sort of a direct path to the power amp section. I used my Krell integrated as a slave for my HT processor L/R front. More and more integrated and stereo preamps are offering the "bypass" as they realize many want better stereo playback and tie their systems together.

I have an old Kenwood integrated with one of those "external processing" loops. That answers how the volume still works but now I am puzzled again as to why the turntable would play through the loop but not a normal input. Unless, there's a problem with more inputs than just the phono.

[markw]

You are right but when he said "external processor" my brain was thinking "processor bypass". This is sort of a direct path to the power amp section. I used my Krell integrated as a slave for my HT processor L/R front. More and more integrated and stereo preamps are offering the "bypass" as they realize many want better stereo playback and tie their systems together.

I have an old Kenwood integrated with one of those "external processing" loops. That answers how the volume still works but now I am puzzled again as to why the turntable would play through the loop but not a normal input. Unless, there's a problem with more inputs than just the phono.

The way I read it was that it played in that shrill, tinny way it did on the other line level inputs, and that makes perfect sense. If he used the processor loop as an inpuit (and many use "tape in" for additional line level inputs), it would bypass any existing internal phono preamp.

[Mr Peabody]

Read Ssarms post from 9/23 6:15, he says, "I didn't hear output from other inputs (cd, tuner)".

[markw]

Read Ssarms post from 9/23 6:15, he says, "I didn't hear output from other inputs (cd, tuner)".

...particularly his edit, which appears to have been added 09-24-2006 at 12:27 AM. .

EDIT: the sound sounds overly bright, I can't hear any bass even with the equalizer knob maxed out. I would think this is happening cause the TT isn't plugged into the phono input?

[Mr Peabody]

I still don't see where you get there was sound from anywhere except the processor loop. It looks to me like he is describing the sound he did hear from the processor loop. It don't really matter now anyway. Maybe Ssarm would be so kind as to clarify for me.

[ssarm@mac.com]

The sound I was describing was only coming from the processor loop.

I got a few quotes from adcom recommended service shops, and I'm probably going to take it to one tomorrow to get it fixed. Even if it's a few extra bux, which it might not even be, I'de rather get the pre-amp fixed than make everything more complicated with an external phono preamp.