1

TS500 Tape Simulator / Re: level problems

« on: June 14, 2021, 04:26:22 PM »

Thanks for the fast shipping!

Today I received the two spare coils I ordered. With the first one I installed, this unit had about 1dB more bass than the other in all settings.
I changed the coil with the second spare part, and now the frequency response is exactly equal on both units. I am finally happy now, as I want to use them on mixbus purposes.

But, there seem to be some quality problems with the coils. I would recommend to check the production, as this is obviously a very relevant part of the TS500.

Thanks again for your help!

Christoph

2

TS500 Tape Simulator / Re: level problems

« on: June 09, 2021, 08:32:03 PM »

It's the coil!

I swapped the coils and the good unit went bad and vice versa. Maybe something broke inside after a short time.

I will send you a request for spare parts by mail...

Thanks again

3

TS500 Tape Simulator / Re: level problems

« on: June 09, 2021, 04:12:20 PM »

I checked the position of HD1, I checked all values from R19 to R24 und C19 to C22. All good.
I resoldered those resistors and caps. Still the same issue

What seems a bit strange... to get 0.52V at TP1 on both units, the DRIVE pots need to have quite different values of resistance. Measuring between the left and middle pin (front view), I get 3.1k on the good unit, whereas the bad unit has 4.0k. Between the outer pins, I get 6.7k on the good unit and 8.1k on the bad one. Is this still within the component tolerance?
I remember that one DRIVE Pot did not fit perfectly through the whole, so I had to resolder it. Maybe I damaged the Potentiometer somehow? Although it worked fine at first...

Maybe swap the DRIVE potentiometers between both units? Or anything else?

I am still sure that both units worked exactly the same in the beginning, so I don't think that I assembled anything wrong.

Thanks again! I really appreciate your fast responding

4

TS500 Tape Simulator / Re: level problems

« on: June 08, 2021, 03:14:44 PM »

TP	bad unit	good unit
1	0,52V	0,52V
2	2,08V	2,08V
3	1,18V	0,97V
4	1,18V	0,97V
5	1,18V	0,97V
6	1,18V	0,97V
7	2,33V	1,94V

100Hz Input / 30ips / Saturation left / Bias right / Output max.

Thanks again!

5

TS500 Tape Simulator / Re: level problems

« on: June 05, 2021, 05:57:13 PM »

Do you hear a change in dullness when switching the speed from 30 to 15 to 7.5 (BIAS on left)?

Yes, it gets duller on 15ips and even more dull at 7.5ips

Thanks!

6

TS500 Tape Simulator / Re: level problems

« on: June 05, 2021, 02:18:37 PM »

Hello JBK,

thanks for your fast support

These value may change 10% from unit to unit because of the input potentiometer precision.
The matching must be based on the meter reading after then initial setup.

I double checked the output levels of both units. The "bad" one only has more gain in the low and mid frequencies. When matching the DRIVE levels, it sounds dull compared to the properly working unit:

conditions	reference	bad unit	good unit
1k / 0,4V	9.2V 7.4V 7.1V	10.9V 8.7V 8.1V	8.1V 6.5V 6.3V
40Hz / 0.25V	9.4V 8.5V 7.5V	11.5V 10.3V 9.1V	8.2V 7.4V 6.5V
60Hz / 0.25V	7.5V 9.3V 8.7V	9.2V 11.6V 10.6V	6.4V 8.1V 7.5V
80Hz / 0.25V	5.4V 7.9V 9.3V 6.1V	6.7V 9.8V 11.4V 8.0V	4.6V 6.8V 8.0V 5.5V
10k / 0.25V	2.5V 4.1V 5.1V 5.1V	1.4V 2.3V 2.9V 2.9V	1.3V 2.3V 2.8V 2.8V

Is this happening with the input shorted?

No. Standard balanced connection from my DA Converter. DRIVE and OUTPUT on 10. In the meantime I noticed that both units behave the same. The LEDs seem to show the level of a standard noise which I could hear when I cranked up the volume when monitoring the outputs of both units. I tried another converter and both units got even more noisy with 5-7 green LEDs flickering. Both converters by itself are dead quiet. When disconnecting the converter from the input of the units, the units are dead qiet, too. Noise level is pretty low though. Nothing to worry about in an analog envirenment. Yet still kind of strange.

Thanks again!
Christoph

7

TS500 Tape Simulator / level problems

« on: June 04, 2021, 03:30:05 PM »

Hello,

I assembled two TS500 and they sounded great and identical at first. Suddenly I recognized a level jump of + 2.5/3 dB on one unit, which was also confirmed by the LED Meter.
I went through the level testing routine, and the defective unit had too much level of 2.5-3V on the 1kHz and all low frequency measurements. At 10k the results were fine.

I also noticed, that with no signal at the input and Drive on max., the first 3-4 green LED show a constantly "pumping" signal, whithout anything hearable at the output.

Ich checked the test pins with a 1kHz sine at 0.4V and got the following results:

Pin 1: 1.4V (+0.25V compared to the working unit)
Pin 2: 6.1V (+1V)
Pin 3-5: 3V (+0.7V)
Pin 6: 2.8V (+0.7V)
Pin 7 5.6V (+1.4V)

I swapped ICs and LED boards between the units, I double checked the parts, resoldered and cleaned the whole board. No Success

I really appreciate any help!

Thanks!
Christoph